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MG Midget and Sprite Technical Hall effect NMC BBS discussion at MG-Cars.net
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MG Midget and Sprite Technical - Hall effect NMC
| Hall effect sensors. Is there a simple way of checking if they are working - or indeed can they go faulty? I am trying to resolve a fault on a modern that uses hall effect sensors as position verification sensors. It would appear that it isn't responding to a confirmation signal from one (or possibly more) sensors but I don't know if it is the sensor, the position of the hardware or something in the wiring. |
| GuyW |
| Guy
YES Hall effect sensors can and do die- If it's a 3 wire sensor then it should have- -Power supply--usually 5v on a car -Earth -Output--The output should go on / off to equal the Supply voltage (5v-0v-5v-0v-----)as the blade creates a magnetic field and then not as it passes the sensor---just hook your multimeter up to earth and output wires The advantage of Hall sensors compared to inductive pickup style sensors is that with an inductive pickup the tonewheel or whatever it's measuring has to be moving to generate a signal, whereas a Hall sensor will operate at zero movement-, If the tonewheel/blade is at the sensor creating a magnetic field there will be an output then away from the sensor, no signal----The Hall sensor therefor can be tested by simply moving the tonewheel/blade into then away from the sensor for an on/off output, as against an inductive pickup needs some speedier movement to produce a signal IF, it's a 4 wire hall effect you're testing then it gets a bit more tricky--it'll still have supply and earth but the pair of output wires (usually coloured the same) are actually part of a circuit, sometimes completing a power circuit but sometimes an earthing circuit---You need to test each/both output wires seperately and depending on the circuit your meter will need to be between earth and each/both outputs -or- if it's an earthing circuit measure between supply voltage and each/both output wires Hope that's clear enough to get you going willy |
| William Revit |
| Or if you have access to a higher/deeper level scan tool you can do various readings and tests for the sensors and their communications/connecting wires/connectors, this can be done in comfort and probably without getting cold and dirty, particularly if you have an old-fashion type assistant with you that must be "hands-on" to feel they're doing something. You could be sitting in comfort and warmth whilst shouting information to your assistant, bluetooth and potential of even more comfort and warmth for the scan tool operative.
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| Nigel Atkins |
| Thanks Nigel, I do have quite a smart code reader,not just a basic number code one. It did help earlier on but it has run out of answers. And thank you for your concern about my working conditions. I do have an indoor workshop for this job.
Thanks Willy. Useful info there. These all seem to be just 2 wire sensors and at least some are mounted on plastic bits so they aren't earthing that way. I presume they just send a pulse voltage as a signal to the CPU Perhaps background will help. Its an Audi A5 cabrio. Acquired with a completely non working hood. There are 31 position sensors for the hood operation and they must send the correct combination of positions for each part of the roof cycle. Its wiring loom has clearly been messed with some time in the past but its impossible to tell if that was anything to do with the current problems! I have sorted most of the issues and it now goes through a full closing sequence apart from the final latching of the rear deck after it has closed. So one task is to find out if the sensor is doing its bit,though it could be the latch motor. On the other sequence (closing) it still stops mid-operation but that's another snake to chase. But from its initial zero movement it is gradually improoved. When it does work its quite impressive to see! |
| GuyW |
| Guy,
as my wife's car is a VAG product I know they have over-complicated, over-intrusive and intertwined computer programs. For an Aldi it's going to be even worse and with a folding roof you have my sympathy (if it's a diesel don't start the engine, it'll choke you). As you probably already know it's very important to have the car battery in a good state of charge for the hood and the computers Are you not using bi-directional to test and fire off the hoods electric bits individually, if so do check the scan tool's programs are up to date before using on the vehicle and depending on which China stolen programmers you have check their systems for info and advice as they are updated and improved via feedback from actual users - also depends on what has been paid for on the scan tool. Is there a hood reset on the scanner or option to reload any program for the roof. Can the final latching be done manually - the latches sensor, switches can sometimes just be a matter of too close or far gapping. If you have the actual VW tool or program it's probably full of errors and omissions, they were not as clever as they thought they were. As you can tell I'm not a fan of German machines, we've had folding roofs and generally they are fine until owners ignore the advice and instructions in the Owner's Manuals and "technicians" do the same with Workshop Manuals and tech info sheets. If we could have got my mate's 2005 Crossfire (a combination of USA and German engineerings!) to talk with my neighbour's scanner (and he paid extra to cover that model year) I might know more for you, but it wouldn't communicate for two previous specialist experts so we didn't feel too bad. |
| Nigel Atkins |
| ETA: Poster deleted post on second thoughts no doubt, I'm less shy and no loyalty or money invested in the products to pretend they're better than they actually are. Bear in mind I've owned quite a few, old and brand new, British made cars so I truly know suffering.
Poster, I think Lidl have less plastic items than an Audi and you should see a Bentley stripped of body panels. Must be German engineering as BMW has been fantastic-plastic for a good while too. I'd be surprised if it wasn't the VAG cars that didn't cause the ship fire. 🤣 |
| Nigel Atkins |
| Sorry Nigel, you've lost me with all that drivel. Nothing of use there! 😂 |
| GuyW |
| Oh dear, didn't realise you were so sensitive about the choice of marque, Poster done the right thing and I didn't. OK, try, is the tool bi-directional, try checking for updates, and if not VAG advice on the repair/diagnostics with the scan tool's systems as users add info, er, hood reset or reprogram options, gaps for microswitches or crud. And of course if it's a diesel if it's a diesel don't start the engine inside or it'll choke you, and outside for that matter. 🤣 |
| Nigel Atkins |
| Guy, When you say 2 wire sensor is that just 2 wires to the device or a 2 wire hall sensor which has 4 wires. If just 2 wires it might be a magnetic reed switch which would be OK for a low speed mechanism like the hood. They can go bad but are often easily replaced. |
| David Billington |
| Sorry Nigel, I don't think the code reader I have is clever enough for that! It reads the Audi codes but doesn't add anything beyond that.
Just 2 wires, Bill. Each component that they are confirming position of has a small magnet, so as it moves into place it registers that. They could be reef switches but all the stuff I have read on various forums and the Audi manual all call then Hall sensors. As the roof opens or closes there are obviously parts that need to move in the right sequence and it needs to 'know" that each stage has completed before the next lever operates. I got the opening sequence to work by adjusting levers, rams and sensor positions so at least I know that each motor and the hydraulic pump are working. The unknown is the final latching motor, plus the last couple of stages of the roof closing dance. |
| GuyW |
| Guy,
that's a shame as the higher level tools offer so much more as diagnostics and repair tool, you can activate and test individual items literally by the push of a button (well touching the screen), check communication to them and even on many items get part numbers and lots more info even pins working or not, communication. Plus they can have back up info and customer feedbacks and info exchanges. If you can get the loan of one it will help no end - and you can still do hands on checking if you want, plus if it's a mechanical or partly mechanical issue tools will be required. If you were nearer you could use my neighbour's machine, after plugging it in (can't risk that) we'd happily watch you using it, whilst we have tea and biccies. I don't know if the scan tool you have can delete error codes for the hood but if it can it's worth trying to do so and live test the hood after each bit of whatever you do as if it's a computer program issue or part program and parts mechanical you never know when they computers will sudden get their knicker out of a twist, tedious but that's computer programs, sometimes suddenly something falls into place. I'm not sure if and what live information you can get on the scan tool from the hood moving itself as we had a total failure to communicate with my mate's Crossfire. Rear latch I saw looks like a reed switch with double set of twin wires. Look for a good parts catalogue and you can look up see the parts, their numbers (and aftermarket alternatives) and see what they look like. Try this - https://catalogs-parts.com/en/ or this - https://audi.catalogs-parts.com/#{client:1;page:models;lang:en;region:rdw} |
| Nigel Atkins |
| Yes, I can delete historic fault codes and re-run the scan as live scan, but it just tells me which systems are faulty or clear. It doesn't log into individual stages as the hood cycles through its procedure.
I got the roof opening sequence reset after sorting the various sensors and easing and lubricating the numerous levers and pivots by moving the hood components through their correct sequence manually. I did this with the ignition on, but not using the hood operating switch. It took a couple of attempts as each component needs to be moved, latched and then unlatched again for the next stage. No cutting corners! I will have another go at it tomorrow, but so far this hasn't worked for the hood closing sequence. Something isn't quite right. It may be that I am not starting the sequence strictly at the beginning as the rear deck is shut, but not latched, at the end of the opening sequence. I need to see if it is possible to operate the latch itself manually. But back to my question. Is there a simple way of testing a Hall effect sensor? Would I get a voltage reading between the two wires if I touch a magnet against the sensor pad? |
| GuyW |
| Sorry Dave, I didn't respond to your question. The sensors I have located so far consist of a small block about 8mm square with just two wires coming from it. Looks like a bit of chocolate! I think that the component that it is sensing has a magnet positioned so that as the lever, ram or whatever, moves into position the magnet comes into close proximity with the Hall sensor, though not generally actually touching it. |
| GuyW |
| Nigel, Is an Aldi really a Lidl Audi? :) Simon |
| S Holt |
| IF they are two wire hall sensors then AIUI the current through them, hence the voltage across them, will change when the magnet comes close. So connect meter, on DC voltage range, to the wires and reading should change when magnet moves close. I realise you may have to be creative making connections! |
| Bill Bretherton |
| Bill, would I do that with the sensor still attached to the car's loom? Ignition on? Or in isolation from the car?
At this stage, all I am trying to sort out is why, when the roof storage lid is closed, it doesn't then latch. The latch is operated by a motor. It is all enclosed, but from what I can see the motor will likely have a worm gear that then drives a toothed gear wheel ( actually a quadrant). This then moves a couple of levers and a sliding piece that operates the latching hook. None of that lot is responding, so the identification parade of suspects is faulty motor, faulty Hall sensor, broken wire or confused CPU. Broken wire would be cheapest, but almost impossible to find. Hall sensor is in a known location and easiest and next cheapest to replace if it is guilty. |
| GuyW |
| Yes, attached and ignition on. IF a reed switch, then that can be tested with ignition off, on resistance range. Resistance should change from zero ohms to infinity. |
| Bill Bretherton |
| Guy,
you're the ideal type of chap to get the hood alignment correct as it takes time, (other) experience and patience and then sorting the mechanics of it all. One thing that was important with the Crossfire was that start procedure (well its sensor(s)) had to be fired otherwise the rest wouldn't communicate. The deck was manual closing/latching (and opening as the hood wasn't working) which IIRC was important. I don't know but think the deck being correct in sequence could be important as there are so many checks before the computers allow the hood to operate. If you're not sorted before (and I remember) I see my mate with the Crossfire on Wednesday I'll ask him as he done a lot of research and studying on his, must have used a small fortune in printer ink printing all the info and manual. "So, how does a Hall effect sensor work? Using semiconductors (such as silicon), Hall effect sensors work by measuring the changing voltage when the device is placed in a magnetic field. In other words, once a Hall effect sensor detects that it is now in a magnetic field, it is able to sense the position of objects." |
| Nigel Atkins |
| OK thanks. Its good to get support and helpful comments here about such things! One needs support to motivate to go and have another session with it! I will report back. |
| GuyW |
| Bit happening here since i went for a nap--
Two wire---Bill's onto it, --could be simple reed switches but Bill's covered that as well so---onwards Guy I'd be tempted to work backwards and see if the motor is getting powered when it's supposed to be first--If it's anything like VW which it is ,it's usually the motor that gets jammed up, sometimes you can pull them apart and lube the worm and gear up and they'll be fine but more often the gear has worn against the worm at the point where it reaches the end of it's travel and it jams up Nigel--I didn't realize you were so anti VAG, I'm sorry to hear that, is there anything I can do--I've got beer if that'll help----lol willy |
| William Revit |
| I was wondering earlier how you can have a 2 wire Hall sensor and had a look and it is possible when configured as a current sensor like the industry standard 4- 20ma sensors, mini reed switches are available also but would be on off. The current Hall sensor is supplied with the supply voltage but the current through the device varies according to its sense reading or switching state. NAMUR proximity sensors work in the same manner as the current indicates the sensor state. If a current reading Hall sensor then checking its operation is likely to be invasive, can the sensor contact ends be accessed.
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| David Billington |
| I think that the idea they may be reed sensors is wrong. They are referred to in the Audi driver's manual as Hall sensors and in the parts list that Nigel linked to. They are tucked away in awkward or impossible to reach places without major dismantling of the hood but there are a few that I can see and they just have two wires.
I was thinking that they worked when magnet was brought close but wonder now if the little square "Chocolat" is in fact the magnet. Would they function if the wire was buried permanently within the magnetic field. And then when an iron component such as a lever came close up to the sensor it would distort the magnetic field and that then cause a change in the Hall effect? Raining today. Yesterday was the first non rain day here for weeks so I was outside, but today it is back to the workshop. I have a list of ideas to try. 🤔 I am tempted by Willy's line of attack on the motor. I like functions one can see and currents, voltages and Hall effects don't come into that category. If I unplug the motor and determine which are the power supply terminals I can maybe just try running the motor off fly leads from a battery whilst it is still in situ. It's about the size of a typical rear screen wiper motor. |
| GuyW |
| David
It's interesting what devices have been/ are used to detect position. My Volvo 240 used a magnetic reluctor device in the distributor whereas the later 740 used a 3 wire hall sensor, a known item of failure. It was riveted to the dissy soft metal base with steel rivets. I gave up trying to peen them and used metal araldite. My V70 has 2 wire abs sensors, one of which has failed twice. I assumed they are 2 wire hall sensors but maybe not. I confess having to look up "Namur" ( not the Belgian town....). |
| Bill Bretherton |
| Guy Found these two pics that show the basic circuits for both 3 and 2 wire Hall effect sensors- The 3 wire is self explanatory with a high/low output signal The 2 wire will have one wire live and the other will be the signal sunk to earth through the resistor giving a hi/lo signal depending on the proximity of whatever it's measuring/detecting Hope that explains it and what to expect testing Cheers willy   |
| William Revit |
| Last half of this is interesting- https://www.youtube.com/watch?v=Oo4CRml5wpI |
| William Revit |
| ETA: I think of crank sensor for a Hall sensor to get the idea
Guy, if you can beg or borrow the right scan tool it will either track down where a broken wire or connector is or get you in the area at least, either power or communication, and if I'm right test the motor you suspect, unless the break is just before or at the motor in which case you know where to start. VW have been into programming their cars for a very long time, a lot long than I expected, I thought Ford were early with their race engines, local connection, but it was before that, forget the year. |
| Nigel Atkins |
| Willy,
no I'm not a VW fan, never have been other than the Golf Mk1 GTI, German cars and styling generally leave me cold. The badge snobbery of some of the German marques over here is annoying and also means the marque and vehicle faults are hidden more and denied, probably to keep the prices high so the owners can be offload them at less loss. My feelings to VW haven't been improved by my wife buying a Skoda which obviously is loaded down with VW bits and all the VW computers and programs (possibly literally over-weighted at times to save embarrassment to the more expensive VW products performance). I do know the German marques a bit as mates and club friends have owned lots of Porches, BMWs (Alpina) and Mercs (including AMG), Audis (including the Lambo ones), Lambos, only know a pre-VW Bentley owner, some VWs. I've personally had to deal with a Merc dealership, but then all English dealerships are as a generalisation not always very good. The original Daewoo car sales set up was different and very good so I knew it'd never be allowed to continue as it was and when Lexus first arrived here with just the LS400 Merc and Jag Dealerships got a shock and really had to up their game for customer service. Perhaps like Jag and Mercs I'm just not old enough for VW ownership. 😁 |
| Nigel Atkins |
| My daughter got rid of a Dodge Journey people carrier. American design, Volkswagen engine, Mercedes emmissions. A real ragbag of unreliability. Rob |
| MG Moneypit |
| Nigel
My VW is deeply hurt by your harsh criticism , I've had to give it some love and gave it it's first wash for the year and tucked it away for the night.even had to give it a vac. inside, It's sulking as I write. I'll ask it to forgive you in the morning but I'm not holding my breath- Just for the record he's (yes, he's a boy car) a MkV diesel turbo and had him chipped up to 145Kw (190Hp) at 160,000 klm and was told to go easy on it or it'll break the dsg box--It's got 350,000 Klm on it now, I drive it fairly hard and it's the daily hack, tows a 8x5 trailer fully loaded quite regularly and never puts a foot wrong and consistently delivers 1000 Klm to a tank of diesel When I wear this one out I'll be getting another, probably won't get as good a run as I've had with this one, but that's the plan--- willy |
| William Revit |
| Update:
I fixed the non latching hood storage deck. It wasn't the latch motor but a broken wire from the Hall effect position sensor. Soldered in a new wire and that is now ok. It will now do it's full top opening sequence, unlatching folding and closing and latching the storage cover. Given that when I started on it last week it did nothing at all that is a positive! It also demonstrates that every motor, lever, sensor, piston etc does work! However the top closing process is still faulty. It goes through each stage except for closing the storage compartment lid. At that point it stops with the lid up like a duck's tail, but with the hydraulic pump still responding. As every function and sensor does now work, this last issue seems to me to be a control fault. The pump is operating but there must be a ram or a valve that isn't getting the instruction to release. So probably a software reset is needed now that everything else is working. Oh for the simplicity of a Spridget hood! Even a MK1 hood is a joy to erect compared to this! |
| GuyW |
| What an interesting thread. I even understood some of it. |
| Greybeard |
| Me too, but kinda wish I didnt. Hi chaps, by the way. Been lurking reading but not interested in politics from General these days... |
| Bill sdgpM |
| (Hi Bill)
Guy, well done, and it was what you thought it was. I'm being serious now, you can reset the car's computers without a higher level scan tool and be belt and braces safe by including a 1 Ohm 10W resistor. Bear with this, buy a 10w 1 ohm resistor, have or make up two short small jumper cables/wires (access to tea & biccies). Disconnect the battery cables, cover the battery terminals to insulate them, use the jumper cables/wires to connect the two battery cables together with the resistor bridging them. Leave for enough time to make and leisurely drink tea (and eat biccies). This will reset to factory settings as any stored electric (for want of the correct term) will be dissipated from the computers making them forget what upset them and got their panties in a twist. Yeap the old 'turn it off 'n' on agen'. I'm sure you won't believe me but there a few ex-computer guys on here (and we don't hold it against them) that can possibly give you reassurance. Otherwise - I have another solution for the reset - my mate brings his Crossfire up for you to sort its roof and he can bring my neighbour's scan tool with him! I can ask tomorrow if you like. 😁 I know he'd travel up as he took he took his Rover 75 to a chap in Wales, who told him the parts that play up on it are the BMW bits, who'd have guessed that (other than previous BMW owners). |
| Nigel Atkins |
| Interesting, 'though somewhat scary suggestion Nigel. I would be afraid that the computer might forget everything else that it was supposed to know as well as the bit about the roof fault! As its not my car I think I won't risk that, well at least not without further confirmation.
I do have one other thing to try. Apparently, if you manually go through a full cycle of opening and closing the hood, this will "teach" the car how to do it properly again itself. Downside is that with all the levers, catches and latches this is not a 2 minute process. More like 30 minutes for each cycle. I did it once and got no improvement. About to give up, it occurred to me that the car's computer likely wouldn't learn if it was still asleep! So I did it all again with the ignition switched on this time. Smart, eh? Well, no not really as when I had finished I found the ignition had switched itself off again at some unknown moment during the operation because it thought I must have left it on by mistake! Dohh! The next attempt was to be with the engine running so it didn't think I had just forgotten. Only by then it was raining again, and being a smelly diesel (as Nigel has already commented on) this needs to be done outside or I will gas myself. Anyway that deserves another attempt. Beyond that, we have a service appointment with an indie VAG specialist for next week who we believe has a clever computer device to try. Hopefully if I have fixed all of the hardware issues thus will finally resolve it. |
| GuyW |
| You want the engine running anyway when lowering/raising the roof - check the Owner's Manual.
Also, take or leave, my word for this all the computers and their programs do not like lower state of charge in the car battery even if there's enough to start the car and the lights seem bright enough (particularly a VW with start/stop). You know how important a good battery is for running and diagnosis problems on a classic multiply this for a modern car and more so for VAG. With that 'battery reset' you can only loose what can be "relearnt". IIRC with the Crossfire it was recommended repetition of up down three times manually to learn. I always think you should leave a couple of minutes for things to settle between each FULLY completed cycle of lowering and raising. My wife's previous two cars, going back to 2003, were both folding-roof cars, both had folding problems (of course they did you know they'd have problems being near me). The second car was a Vauxhall unfortunately when GM owned them and the USA was bailing them out so warranty work was kept to a very minimum, but as you can guess that's many other stories. Thing is, at the time owners were paying £70 just as plug-in fee to sort very easy issues on the car and roof - reading the Owner's Manual would have saved this many times - but also simple fixings/resets for the roof BUT many owners simply would not trust or believe the solutions could be so simple and wouldn't try for themselves given the information (disconnecting the car battery was sometimes one). I could do 5 minutes work or less without getting my hands dirty for some common roof problems, there were other very easy fixes for other common model problems, easy garage money, and as you know it's not that I'm clever or technical, just reading the Owner's Manuals and using other people's simple solutions. Back then I could have charged £50 a time and have people leave the car for an hour, for my 5 minutes work behind their backs - but I'm not like that or I'd be in the car trade. It's 'synthetic' oil and GL5 all over again. 🤣 I know my secrets are safe here. 🤣 |
| Nigel Atkins |
| Yes, you are quite right, I have been running the engine whenever using the automatic roof operation for exactly the reasons you state (and because that's what it says in the driver's handbook!) But when its working it does that in a matter of 20 seconds or so; quick enough not to gas myself. Doing manually take 20 minutes; far too long for my lungs. And of course it's not pulling power from the battery when you do it manually so your logic doesn't then apply. |
| GuyW |
| The running engine gives power assist off the pump if you also push the button for initial raise/lower though surely, you said you had the hood getting half way and near the end of the raise/lower so try pump and manually assisted too - 8 minutes to find out if it works (20secs x6 + 3x 2mins rest periods for car and you).
BUT I'd never suggest you do this indoors with the engine running, or quite frankly outdoors with an Audi diesel! The Crossfire manual hood involves a fiddley farting about with a hooking tool in a blind slot for deck release but my mate has ben doing it so long now he can have the hood up or down in a few minutes. That's why the roof is up here, scan tool didn't work but camera did. Good luck but seriously don't be in any fumes for too long. |
| Nigel Atkins |
| Willy,
(all tongue in cheek as you know - but for other viewers) you'll get me in trouble for thread drift, luckily Guy will be fully occupied for a while yet with the hood. I don't mean to upset you or 'im, it's each to their own, though I'm not sure 'im deservers any cosseting. You could probably test drive a new one without needing to leave home as they're all Infotainment centres on wheels now, put the ambient mood lighting on and watch a few of your old home movies on the dash screen. I think they have a computer to control the computers now. When my neighbour tested his scanner on my wife's very lowly VW product from 2015 it had 638 data points for just the engine and IIRC(?) 138 for the battery management system (start/stop model). I couldn't guess how many for other cars with greater interior or comfort stuff or windscreen alignments, rear views mirrors cameras, etc.. You obviously got your car with one of the DSGs before VW decided they'd put the wrong oil in or more likely insisted their oil supplier blender a semi-synthetic to VWs specifications then after box problems swapped to a mineral oil so that it is clear it was the previous oil at fault and not their box design or oil specifications and so the 'technicians' can easily see a difference in the oil bottle labels (cynical me, no way). But an automatic is handy for the older customers. You want a good heavy car if you're towing, you choose wisely. My midget could do 2,000kms, given a big enough tank. I understand they can be good cars but with their the drab but oppressive interiors and exteriors they just don't appeal to me, a mate once had a VW Bora, only one letter out. 😁 |
| Nigel Atkins |
| On this car, you cannot combine powered roof operation with manual. It's either one or the other. As soon as you commence a powered sequence it then locks up the operation of pistons etc at which point nothing else can be moved by hand. If you do want to do a manual operation then various catches and contacts need to be manually disabled first. And as you say this involves manipulating components by feel in awkward places impossible to get a line of sight to. |
| GuyW |
| Its giving you a good fight.
Full manual sounds like the type of job for the owner (I'm guessing offspring) whilst you look on and give instruction. Another thing to try (perhaps) if you've got the car's Driver's Handbook it'll tell you what few things might need sorting after a battery disconnect (time of day clock?), disconnect the battery and give it a charge overnight, reconnect it tomorrow, try the hood - if it don't work what have you lost (you've not put the year of this A5) and a bit more charge in the battery for all those powered tests when you get it working, save choking on the fumes from running the car. |
| Nigel Atkins |
| Did that at the weekend, Nigel. (New battery, but a top up charge as well, that is) btw, it's my son in law's car. |
| GuyW |
| Did you leave the battery disconnected for a reasonable length of time and whilst the battery was off turn on electrical items to try to drain the computers of any stored electricity 'capacity'.
Son-in-law - why are you doing the physical work, has he been threatening you with dodgy care homes, and emptying the sheds of parts to the tip as house clearance, I can get "the social" involved, just use the codewords "clean diesel" and I'm on to your local lot, venerable adult. Write it down in case you forget, if he sees it he won't understand it as an A5 diesel owner that's for sure. 😉 I might be run out of ideas for the car but I've plenty for dealing with family. 😁 I expect you'll have it all sorted by the time I return, good luck. |
| Nigel Atkins |
| Hi Nigel, Thank you, your post made me chuckle, a good start to the day. "venerable adult" (venerable: def. an unintentional error regarded as revealing subconscious feelings) Freudian slip? Ray |
| Ray Rowsell |
| Guy--Good progress then--good find.
I'm not sure what level of scanner you have, but if you have a code reader that talks to the VAG roof system then 'sometimes' you can be lucky by doing a trouble code erase, then without testing for codes between do another erase, If you do this three or four times straight off without testing or doing anything else, some systems will reset back to base settings--no guarantee but worth a try- IF you don't have a scanner then Nigels method 'can sometimes work'-BUT all due respect to Nigel he's missed a bit out--with the battery disconnected and the resistor across the cables, then the ignition has to be turned on to the normal run position and you have to have it like this for at least a full minute, or more , anything less and it won't work--It has to be long enough for the capacitors to drain off - It's probably a Bosch controller---Back when I was into this stuff fulltime the trick for clearing/resetting Bosch controllers was roughly as Nigel suggests (which would probably work with the key on) but slightly different--- If you have the radio code---you'll need that--- I guess you have that having replaced the battery, so-- Disconnect the battery, one cable will do and safely set the cable aside Handbrake on Turn the ignition to the run position Push your foot on the brake pedal and sit there for the full minute -plus 100% safe to do- Doing this drains the charge from all the backup supply capacitors etc that keep the Keep Alive memory in the controllers alive, through the brake light globes and the backup in the cluster through the handbrake warning light---It won't wipe any tables or anything from any of the computers in the car, it won't wipe your key codes or remotes but it will wipe any RAM (random access memory) from both the engine and DSG box if it's a DSG----No big deal,it'll just go back to base settings and have to rebuild it's memory to suit how it's driven--You might notice one or two different gearchange points until it's had a bit of a drive round town but no different to a new car learning---- Worth a try -or Nigel's resistor method or both, no guarantee it'll work but definately can't hurt anything Just leaving the battery unhooked won't work either as the capacitors keep the memory alive--the capacitors have to be drained Not sure with Audi but some cars have to have the handbrake on for the roof to operate properly willy |
| William Revit |
| Ray, it might have been a Freudian slip, I would mind Guy as a father-in-law, I'd give him plenty to as I've got a Midget but he'd have to update his oil beliefs. 😄 Odds are it was one of my many spelling, writing or spellcheck mistakes, spellcheck can't cope with my misspellings, but perhaps it all was Freudian. I read your venerable as vulnerable so your post gave me double laughs, about myself. |
| Nigel Atkins |
| Interesting development. Today's task was to do a manual open, close, cycle, but this time with the engine running. Theory being that with the ignition on, the computer would be awake enough to watch closely and be able to copy the sequence. Unfortunately after doing this computer just says NO. "roofcannot be operated". That's a retrograde step from yesterday when doing the exact same thing but with the ignition off got it to function fully for opening the roof, and all but the final rear deck lid closure on the roof close cycle.
Repeating the operation again today for a second time with ignition off and its back to yesterday, 90% success position. I have tried running and deleting codes but not the triple delete that you suggest, Willy. I might also try your CPU reset if I get time. If not its off to the VAG specialist man. He is do ing a software remap anyway so can run his systems on it. I am fairly convinced it is a programme issue as all conditions of the physical positioning do operate at one stage or another, but just not in full sequence. I am reminded of that Eric Morecambe piano sketch with Andre Previn with his comment " I play all of the right notes, just not necessarily in the right order" |
| GuyW |
| Probably not the case but wondering is it a safety thing that it wont operate with the engine running? Trev |
| T Mason |
| Willy,
good to have some conformation as I often get disbelieve or the urine grossly extracted on stuff like this. As you know it depends on the age of the vehicle as to which level of voodoo might work and there seems to be so many variations of what to do to get it to work. Given the scepticisms it's a gamble as to how much you can suggest or persuade someone to try. I thought ignition on was for airbags but personally with the battery disconnected I'd not mind turn any and everything on and press the brake pedal and doing anything else as its quick, free, easy, can be done in reasonable or good comfort and other than the battery connections perhaps keeps your hands clean, the sensible way to do any car repairs. Of course touching a button on a suitable scanner screen is quicker and easier. I like the idea of erasing the codes three or four times but the likes of you can suggest this, the likes of me and it's taken as not being sure of what I'm doing which is why it's best for to not have the person there or we know each other well. Funny thing is if it was their home computer or phone they'd accept you might have to try a few times, it's difficult to get through to car owners that they are just (very stupid) computers with not particularly high level parts inside then. I'd never suggest only doing this for a minute or longer - you'd never get a mug of tea and biccies made served and drunk in that time, and the value and effectiveness of the work is often judge on how long it takes rather than how quickly it can be done, people find it reassuring that it takes time if they're their to witness it. Again it depends on the age of the vehicle and whether it's a factory fitted 'radio' but from what I've been told VW at least going back a good number of years will retain their codes - but I'd not risk it with my neighbour's 2005 Merc as they have no record of the code and the radio is so important. Cleaning a lot of engine or gearbox sets can be a good thing as often particularly with over-complicated, over-intrusive, intertwined computer programs like VW's has them with their knickers twisted so starting again is a good thing (not that the computer really learn anything, that's AI). Also consider many older VAG diesels are going to be so sh*t'd up the computers will have ben running themselves ragged to keep up with all the constant adjustments required. The gearbox (especially DSG and CVT) also throws up something that owners find hard to accept especially from the likes of me, that a "gearbox fault" could actually be an engine fault (or their computers programs) and vice-versa or if you have the privilege of dual mass you can throw those in the mix. The disconnecting the battery was more about getting the battery more charge as messing about you can forget how much you've drained the battery and I'd no information about the battery at that time. I should have known Guy would have already considered this but as you know a bit of psychology is often needed even if you're working on your own car let alone suggesting what others might try. I've no idea where any particular Bosch part is actually made and by who but 'factory' parts aren't always the best as you know, as a generalisation I prefer proper Japanese parts made in Japan but I don't know about Bosch controllers or much else and don't want to give the idea I do. I do remember the TT when it first came out and all its problems and 'proper' Audis of the 70s and '80s (90s?) before VWs tie up , before BMW type started buying them. Judging by my neighbour with his Audi A5 I don't think the handbrake has to be on for the roof to operate. |
| Nigel Atkins |
| Guy,
you do sometimes have to have the correct level of scan tool to really delete the codes, some seem to say they have cleared the codes but when using a higher level took they still show. Of course it doesn't matter how many times you delete them if there is a fault that remains to trigger them again. Do try the quadruple erase after each action. The brake pedal pressing might be good for VAG as until they sorted it some (one model?) had computer programs that would put the car into limp mode from a fault or perceive fault at the brake lights, no really, too clever for their own or not as clever as they think they are, you decide. The 'drain' methods I think at a certain level can be a personal preference or experience so if you think of something that might be related to that particular model or car that might help then add it in. I know you will want that last 10% but really if it's going to a proper specialist (my mate's Crossfire went to two specialists) then it will probably be very quick for him to resolve with the right (scan) tool. If you can I'd be very interested to know how this is resolved and what make and model of scan tool the specialist uses if it's not a VAG machine. For interest you might also want to look at the number of data points for the engine and hood they're just numbers at the bottom of the screen so it's not hard to see or be intrusive to the chap doing the work. |
| Nigel Atkins |
| Trev, I don't think so as on A,5s you can operate the roof at up to 30mph. Perhaps what you mean is safety in not operating it manually with the engine running on case it suddenly starts to move and traps parts of your anatomy? I don't think that either as it didn't prevent the manual operation in any way. |
| GuyW |
| Nigel, I didn't doubt your instruction about how to drain down residual voltage for a computer reset. I do however have some misgivings about VW and Audi (and other brands) over consistency. What works on one model year or in one country doesn't necessarily work on another. I was shelving the suggestion until I had tried some other ideas first.
If you find people often doubt you and won't take onboard your advice, perhaps it is because for years you have yourself repeatedly claimed to know nothing about such things. Other than for beers, that is. And maybe oil when it's of a similar formulation. |
| GuyW |
| The up to x MPH throws in a load more of the computer programs and interactions and checks, sensors, etc., making something that was already complex even more complex getting much nearer to car Dealer/manufacturer level programs and scan tools. Luckily the Chinese seem to have had (given) access to these programs so (relatively) lower cost publicly available machines do seem to be available. |
| Nigel Atkins |
| For anyone still persistently interested in this non Spridget topic this is the most comprehensive video on this particular hood operation I have found. All 14.32 minutes of it!
https://m.youtube.com/watch?v=jV3FHW6XN4s It goes through it several times but detailed version starts at 6.00 mins. My hood gets to position at 7.55. Everything up to there works just fine so it could be what he calls the "rear bow raised sensor" Except that is working at an earlier stage in the roof opening sequence. Anyway I am about ready to leave to the specialist VAG bod with his ultra-scanner now. |
| GuyW |
| Guy,
good gawd, the computer math geek presentation of the VCDS system certainly suited the chap that made that video, instructional but reminiscent of someone reading the telephone directory as a bedtime story. I hope you've not had to put up with a scan tool (or app) that presents in that fashion, unless you like quoting sequences of 14 digit code numbers.. I had no idea the Ross Tech VCDS front facing looked like that I thought it was only their techie website solutions that had that type of presentation, if that's what the end users sees it's dreadful. The Chinese machines have a much more end-user friendly presentation (if the odd word or phrase shows it's been translated to English). Have a look at what your specialist uses, if its the VW Dealership one I've never seen it and wonder if many Dealership 'technicians' have judging by some comments I see. If it's written and presented in the same manner as the VW Driver's Handbook it will make what should be simple explanations very difficult to follow. If your specialists uses Think, Topdon, Xtool, or stuff like that then their presentation will show you how embarrassing that Ross Tech VCDS with its typical computer nerd closed-shop presentation, made unnecessarily techie unfriendly looking to exclude those that just want the information presented in a clear and easy to understand and use way. BTW - I mistyped in answering Ray, please don't cancel your adoption of me, I meant to put - I wouldN'T mind Guy as a father-in-law, I'd give him plenty to DO as I've got a Midget but he'd have to update his oil belief" |
| Nigel Atkins |
| Nigel
Just for your amusement while we're waiting for Guy to recover from visiting the Vagman- Here's a vid. of the old original VAG machile People were scared of it but really it was a real simple machine that ran through to about '96 then VAG EOBD till 2000 -- then VAG OBD11 2006-- This old machine used to be worth it's weight in gold and would still be good now on the older vw's Only thing was it was sort of binary based so you had to have a magic memory or the monster numbers list to operate it--but it was good My little Carmen scanner still reverts back to this number method when it's hooked up to a VW https://www.youtube.com/watch?v=p3ycXaY2tgg oh, and by the way , you've probably thought about this anyway, but the key on for resetting the memory of controllers does the same thing as your resistor, but uses the stoplight globe resistance ,back through the ign switch to the various ecu/pcm etc controllers to dump the capacitors willy |
| William Revit |
| Hi Willy. Yes I've gone quiet on this as no further action on the hood fault. (Cabrio soft top, for USA friends) I copied out your advice for clearing and resetting the computer to have a go at that, but the owner declined. He wants to leave it to his man with a VAG device. The car is booked in for a remap, but I have warned him that this needs sorting first! If he gets it remapped and then after that has someone else try and sort the hood programme it is likely they will wipe his expensive remap! Am I right with this?
I presume a good remap would involve a scan and check what is set before then adding the remap. If so, then it would be a good opportunity to check the hood settings first, but for now its out of my hands. In the meantime I have been refixing the rear glass window which had come adrift from the fabric hood. It glues in but it was a tricky job involving several attempts with multiple clamps needed whilst the messy screen adhesive sets. Nigel would love it! |
| GuyW |
| Hi Guy
That's a shame, that you didn't get to try the fault clearing method--- On the remap/reprogramming question---When the computer is remapped, 'all' the original program is wiped off completely and the new program replaces it. There can be a another situation where a car manufacturer discovers a fault in a program and they send out what's known as a patch to fix it, This is a mini program that gets burnt in over the original program without removing that program first, but a complete remap is the best option- Sometimes you can do what's called a suck and blow which is what happens when fitting something like a new instrument cluster--What happens there is the scanner/VAG tool is hooked up and all the info is copied (sucked) into the tool-then the cluster gets replaced then the info is downloaded (blown)back into the new cluster-------You can cheat sometimes with an issue like your roof problem, If you suspect it to be an introduced glitch and there's not an upgraded program for it. by sucking out into the tool then reloading it back in---doing this returns the program as loaded originally without the glitch- An example of this is Ford Focus/Mondeo--If one of these runs out of petrol and you try to start it a couple of times and it cuts out, it gets that in it's head and when you refuel it, they usually start and cut out straight away but will start second try and be ok--same thing tomorrow, start it ,cuts out, second try ok and that will keep happening for probably 20-30 first starts until it relearns what it's supposed to do if ever, but if you suck+blow it, it's instantly fixed. As far as remapping the roof goes, before any remap the system should be checked for DTCs and any faults fixed before the remap--If there's no DTCs then yep go ahead and remap.- Don't worry about losing a remap, it's almost impossible unless someone is trying to program the module with another program and stuffs it up---Doing resets and wiping codes etc has nothing to do with programming/mapping, the only way programs can get damaged/glitches is by sudden changes in electrical supply (spikes) usually by unhooking jumper leads immediately after starting a car with a dead flat battery, or electric welding on the car without the battery unhooked nuff from me---it'll be interesting to see what the Vagman finds with his scanner, depending what he's using it may well do a much deeper diagnosis and come up with something-- If the roof wasn't completing it's full action I'm a bit surprised that it wasn't throwing some codes at you---If in fact it wasn't then yes it may well be a glitch in the programming and a program remap will fix it willy |
| William Revit |
| Willy,
loved the video, he's the 'battery voodoo' guy. I now understand why that VCDS is so ugly and nerdy, it retains backwards compatibility of the tradition of VW's traits of order but little imagination, flair or aesthetics. Yes the brake pedal drain makes sense but with the newer cars I've no idea what other interfering things there might be plus the resistor is more about visual and physical reassurance, a sign of protection and again if someone like you says you only need to push the pedal it's accepted whereas someone like me doing it looks like I don't what I'm doing or I'm pissing about or doing a con (or an FL as I call it) or "selling snake-oil" as others might have it. This is his battery voodoo video but it is from 5 years ago I'd certainly be looking for a pre-drain for new cars with computer programs for I don't know what, probably Microsh*t controlling the the camera in the rear view mirror and Alphabet your active speed sign controls. 😄 Don't try this at home kids, for Willy's viewing pleasure only. 😄 - https://www.youtube.com/watch?v=vYtyDX9RTWs |
| Nigel Atkins |
| Guy,
Willy again not living here has more faith in the trades people here, as you well know it's less so with me, from much experience. It depends what is meant by the remap, as it's an Audi I guess it's a get more power remap rather than taking out the programs and reloading the original factory programs for computer gusset straightening, as you do with other computers when nothing else seems to work, a reload - uninstall and install fresh. If increasing power (by reducing manufacturers margins) then a decent chap would first check the car and engine are up to it but many seem to be little short of roadside, or Tescos carpark "upgrades". If it's a reinstall of same then you could (would?) do the hood anyway and then some see what's wrong with it, bit like doing the MoT and then see what work needs doing, work to minimum standards. People over rely on these scan tools now, particularly the low level readers, as you know now just because there's not a code doesn't mean there isn't a fault. Humans have ears, eyes, nose, sense of feel and brain so can detect something is wrong often before a code is thrown up. Then when there is a code some take that as the answer rather than the starting point of diagnostics and order the part that the code relates too to find the issue remains. The VAG programs are over complicated but then perhaps that helped with hiding stuff to fiddle things for emissions but more likely like a lot of programs with having to keep the old layered systems with all their faults and mismatches (patches on patches, weak foundations), I forget the word now (ETA: legacy). With the "relearning" of settings IIRC you can see the number required somewhere for reset to establish, on a higher level scan tool you will see how many times the error has occurred, lots of info. A good chap with the right scan tool with have the hood sorted in minutes now you have done all of the hard work. Step away from an Audi and an Audi owner, many would have been BMW drivers a decade or two back, just be thankful they're out of their cars. By sheer coincidence yesterday I was behind a 16 plate A5 TDI and not a hint of smog, but then I was only behind him 50 yards before he turned off towards the local MoT station. Later I had an A6 hooked to my boot going through town as soon as the two lanes came up I moved left so he could go in right lane but he then immediately swung in front of me judging the queue in the right lane at the traffic lights to be slower. Generalisation and stereotyping I know but mid-30s male in an Audi then get out of his way and keep away from him. |
| Nigel Atkins |
| Thanks for the video Nigel, yeah I agree with most of it BUT, them battery terminals need a good cleanup, grotty terminals are a no no for modern electrics---and in saying that he had his alligator clamps onto the thru bolts that were floating in the grotty terminals and probably not making contact--would have been much better on the (clean)terminals themselves---but yeah, all good
On the scan tools--there are scan tools and there are scan tools- an example is most generic testers will come up with a letter and four numbers eg P1234 but with Ford for example you get an extra number telling you if it's a pending code (temporary fault) or a hard fault and also the codes run in number order segregating them. which most techs wouldn't have a clew about--it's just a number to them The 'best' scanner I've used is the Kia factory one. It was really messy to begin with by having to have special codes to get into stuff and the code words/numbers kept rolling over so you had to apply for new codes all the time(crap)but now each tech. has a number and password(still rolling but lasts for a few months till you need to renew)--It's designed for a laptop but we had a 26"screen plugged into it for the w/shop--The beauty of it was the workshop manual was online as well and linked to the scanner and Kia updated all the time with known faults (you were encouraged to report any fault you found but they must have been going through warranty reports anyway) So you'd plug in ,do a scan, get your DTC, find out what it was, go to fixes and get sent to the relevant area of the w/shop manual and that would also display common faults for that code- eg.--I had a Carnival with an inop cruise control once, came up with the a code, went to fixes and the shop manual and it showed an actual close up colour pic of the rear body module with the connector not fully seated leaving the end contacts not touching---so ,in the back we go pull the cover off and it's just a blank module, no plug--unbolted it off the frame and pulled it back and sure enough there pas the plug sitting crooked, pushed him in, click, and all was well-----how good is that And also you can poke your Kia vin. jn and it'll come up with all the upgrades that can be applied to that particular car and actually explains what they are for and why, so if you have an issue you can flick through them and go gotcha-- Cheers willy |
| William Revit |
| Willy,
yeah those terminals and the debris in the microfibre cloth he used as insulation, he did wipe a battery post before reconnecting and mentioned about cleaning and putting earth back first but I am totally with you on the connections being clean (secure and protected). I like the idea of a large monitor, though 26" would be small now, a mate had a 32" as a desk monitor about 20 years ago but it was because you get something free with it and it was his company so he could do as he pleased with company money. You'd expect a South Korean company to be good with computer things but they have to do R&D Chinese are better as they just get the car companies to give them all the info, American car companies thought they were being clever and dealing with stupid people whereas the Chinese (and everyone outside of American car companies) knew it was actually the other way round. The Chinese systems work with feedback information to improve their programs and systems and have forums and advice too. As an example my neighbour bought a system that comes in a case with all the lead connectors going back to the 90s and possibly further, handheld tablet, bluetooth to plug-in, built-in camera, cloud based programming and coding, OE level, bi-directional of course, pre and post scan reporting. He bought programming back to 2004 to cover his vehicles up to it's realease date but would have to pay for updates for new vehicles after that. I think it covers about 155 vehicle manufacturers names, some I've never heard of. It's for Europe (which includes UK despite what many may think) but not USA but anything can be added. As it was a model that was being superseded he got it for a lower price but even at full price it's only in the hundreds and not thousands of pounds. It covers VW, that must take up a lot of space, on my wife's 2015 car it had IIRC 638 data points for the engine we just looked at four live graphs as neither of us have good eyes so he also put the programs on an old laptop he has for the bigger screen but we really needed a 20". I suggested he could use it to get some money back on it but he said if he sorted anything then the owner had to change the tyres in the next 12 months it'd be because of him plugging the scanner in. Like me he has dealt with the Great British public before and knows they can be very unreasonable at times. |
| Nigel Atkins |
| Ha ha ha ha ha--Nigel if he's got a big one that covers VW as well tell him to leave the lid open a bit to let the smoke out--LOL , with the screen size, yeah that was the issue with the Kia tester, there was that much info crammed on the laptop screen you could hardly work with it but with the 26" screen it was a whole new world
With your mate's crossfire, there's a fella up the road from me here that has an AMG modded one, bit weird having a German modified US car but it's not a bad looking thing--I didn't know there was such a thing until i saw this one cheers |
| William Revit |
| Willy,
my neighbour put the system on to a smoke coloured laptop as it included VW. By coincidence my neighbour 2005 A5 diesels cabriolet is up here, it's all black with smoked tinted rear number plate, rear lights and side windows. Well that's what I thought but seeing it on the road once I now think it perhaps started out as white with stand rear number plate, rear lights and side windows. I didn't know AMG done them too, there was a souped up version anyway. A couple of mates in the club had them when they were new, both coupes and following them at the time they looked like they had dragster rear wheels, now a standard shopping trolley has to have oversized wheels and over-wide tyres. The Crossfire is a Merc SL (a car ideal for a trendy granny at the time) crossed with American bits and styling, what could possibly go wrong. My mate made the mistake of getting the 6-speed manual then worried about getting it into 6th at 50mph for fuel economy, on a 3 litre two-seater! I don't suppose he's so worried now he got a 4.8 Mustang (Foxbody). I've no idea where he lost his taste he used to have three Supras. I was lent the Crossfire once, as I'd got our car locked in a car par overnight, and I don't know if it was the tyres he had on the Crossfire but it was horrible, not settled even on the warm sunny day, I never went over 50mph and couldn't wait to get it back. The Crossfire folding hood is all Karman my mate told me, no idea whose programming though. As my neighbour was unable to sort the hood and he done some improtu videoing of some of my mate's cars for his YouTube channel. Here's the Crossfire, funnily enough they forgot to put the hood down, all done quickly on a cheap s/h camera. Details of the STR(?) model are included. - https://www.youtube.com/watch?v=bg4qiHW4ERc |
| Nigel Atkins |
| Always disliked the styling of those Crossfire cars, especially the rear view Ugly. Contrived. |
| GuyW |
| They did at least look different to other cars when they were new, the coupes were a bit better looking but had a crosspiece on the boot floor, like the Nissan 350Z soiling the boot as a boot. Merc inside and I'd guess (never driven an SLK and I'm still not old enough so don't know) similar to drive (so boring) but from the mate that had one new they can apparently sustain high speed (abroad of course), the long very straight (and very boring) roads suit them. |
| Nigel Atkins |
| You've got me thinking now Nigel, from memory this thing here has AMG badges on it--not sure, I guess i'm going to have to go have a look--usually ends up with more work when i go to his place though--decisions decisions, will I go---might go Sunday |
| William Revit |
| Saved myself a trip, Had a couple of pics of it. It's got SRT on the seats by the look of it and AMG badges on the side   |
| William Revit |
| Willy, the engine was AMG but they didn't have the AMG badges, here at least. You can get (recently-ish) Mercs in AMG trim level but they're not AMGs. I saw a SRT-6 once but it was parked in the micro-brewery car park so I didn't have time to look at it as the bar was open. I find it hard to imagine that even an AMG engine could bring interest to a car of such unfortunate parentage, perhaps hence the badges. |
| Nigel Atkins |
| Willy (Guy),
by coincidence Monday my neighbour asked me to have look at her battery charger as it'd stopped working just as she'd finally got around to charging it from last summer. Its facia fuse had blown, I noted a deep scratch across the positive battery post top. I asked how her car was going (2005 Merc A-Class) and wot d'ya know the gearbox code and ABS code had returned along with a couple of new associated to it. So as the battery had finally been fully charged Tuesday I asked my other neighbour about using his scan tool on it and perhaps do a short video. A few stored and current error codes were deleted but 2/3 remained current. As my neighbour with the scan tool wasn't feeling well there was very brief videoing and I was left to see what the test drive would show. Basically lack of use, very short journeys with cold starts. Once the box had the slightest warmth it was fine (for a Merc CVT) and I'd previously advised doing manual 'shifts' if required. I passenger'd and could hear different brakes chirping at different times but after a bit of braking things improved. My neighbour asked me to take over the driving to see what I thought and the car went well no problem with the 'gears' or 'kickdown' acceleration, such as it is, fine at a run at national speed limit on a dual-carriageway. On minor roads low and high speed straight line braking was very impressive. I didn't try ABS style braking as my passenger seemed more comfortable being the driver. Anyway, I thought you might like to see the (attached) report after clearing codes. Note the machine tells you what to look at specifically. The connecting socket's under the front wheel arch liner, so I'll go over and watch her working on that when the weather is a lot better and warmer. |
| Nigel Atkins |
| Cheers Nigel
We mustn't jump to conclusions, there's thinking that needs to happen The machine isn't being over specific--depending on how good it is you should be able to measure current data in a couple of ways--road speed of all wheel sensors while driving, which should obviously show that R/F sensor as inop, but also there should be the ability to measure sensor resistance with the scanner--if it doesn't have that capability then you can disconnect both front wheelspeed sensors and compare their resistances unless you have a spec for it. Most commonly it's a stick/stone or something has tangled with the wiring and broken a wire down near the hub somewhere (repairable usually) Because the code didn't clear it has to be a circuit problem as opposed to something like a bent tonewheel which would clear but then return when moving the car comparing the resistances at the connector under the guard would be first step--if they're equal then it's further up in the engine bay where that pesky mouse has eaten through the wire--lol You wouldn't believe how many false wheelspeed sensor faults get thrown up from crap on the sensors, usually from when someone has had their disc rotors machined with one of those on-car disc machines and the machinist (for the want of a better description) hasn't cleaned all the swarf off the wheelspeed sensor when he finished--but that won't be the fault here as it's showing as a hard fault |
| William Revit |
| Cheers Nigel
We mustn't jump to conclusions, there's thinking that needs to happen The machine isn't being over specific--depending on how good it is you should be able to measure current data in a couple of ways--road speed of all wheel sensors while driving, which should obviously show that R/F sensor as inop, but also there should be the ability to measure sensor resistance with the scanner--if it doesn't have that capability then you can disconnect both front wheelspeed sensors and compare their resistances unless you have a spec for it. Most commonly it's a stick/stone or something has tangled with the wiring and broken a wire down near the hub somewhere (repairable usually) Because the code didn't clear it has to be a circuit problem as opposed to something like a bent tonewheel which would clear but then return when moving the car comparing the resistances at the connector under the guard would be first step--if they're equal then it's further up in the engine bay where that pesky mouse has eaten through the wire--lol You wouldn't believe how many false wheelspeed sensor faults get thrown up from crap on the sensors, usually from when someone has had their disc rotors machined with one of those on-car disc machines and the machinist (for the want of a better description) hasn't cleaned all the swarf off the wheelspeed sensor when he finished |
| William Revit |
| The code reader the A5 owner has isnt very sophisticated. It runs through the systems via OBD socket and posts pass or failure for each one. It will also show current, stored or historical. So it shows the "Cabrio roof system" as a fail, but then we kinda knew that! I am not familiar with the code reader and owner has mislaid the handbook ( Nigel will love that!) I am wondering if one can drill down the fault code readout for more detail but it isn't very intuitive and I don't like electronic things at the best of times!
Anyway, an update and progress. The mapping guru was persuaded to run his scanner on it and it came up with "soft top latching fault" - which we also knew but then a code. F802 which we didn't. He wont get further involved but I have traced this back to a sensor on the hood frame supposedly somewhere above the drivers door. I think that if that sensor doesn't register the car doesn't know if the hood is fully forward and won't then go on to the next stage which is to slide the rear deck cover down - i.e exactly the point that the system stalls in real life. So I am hoping this is the problem, though of course as with all fault finding, one shouldn't assume there is only one fault! Frustratingly, I cannot get back to further investigation until later next week so you will have to wait for the next instalment. |
| GuyW |
| Willy,
you'll be pleased to know all the items you mentioned had already gone through my mind. The great joy of the machine is that you can hold it one one hand whilst sitting in the comfort of the car going along and look at, record, graph, live data without get your hands dirty! Checking the sensor with the scanner for how many data points I don't know but it'd only be restricted by what the car can give. The sensor details will be given including part number, possibly serial number, when made or fitted, it's very far away from a code reader. Unfortunately as my neighbour wasn't feeling well from starting medication and it's his toy and he's not getting a penny from helping out he didn't come on the test ride and I didn't like to say to leave his toy with me that he's spent a lot of money on without telling his other half (no I don't understand such relationships either). As I often say most servicing, maintenance and repairs on our old cars boils down to clean and lubricate but it also applies to newer cars too so my thoughts were to get the brake cleaner and/or blowing vacuum cleaner around the brake hub area - but to do this means removing the front wheel, then you might as well remove the wheel arch liner to check the plug/socket connections (clean, secure and protect if required) and wires (which then go to the congested and dirty engine bay). All this involves a lot of mess and getting dirty, risk of breaking plastic fittings which none of us may have stock of and having done this it's also about 85% of the work involved in replacing the sensor if it's not the socket connector or wires. A lot easier is to wait for warmer weather integrate the sensor and its wiring and connection with the scanner then perhaps and go for a ride and let the scanner do the work before deciding whether to risk a £25 sensor if required - but all whilst keeping warm and not getting hands dirty unless absolutely necessary. |
| Nigel Atkins |
| Guy,
I doubt the code reader instructions would tell you much other than the buttons and menus (if any) on the tool. You can get information about the codes but many machines just give the basic generic codes. Better machines will tell you a lot more and connect you to the internet for more info or to buy the part. As Willy has put you can use the better machines to zone in and actually test items. See attached photo taken the other day as an example for you to give you to give an idea of detail you'd get for a powered latch or sensor. To be fair the Ross Tech VCDS website does give lots of information about codes, but I can't see anything for F802 (sounds too short code number). I think you are spot with the problem on so need repair or replacement and/or reset. I can understand why the remapper doesn't want to get involved but not why he couldn't give you more info a print out of the fault code result on the hood at least, unless that part of his system is shallow level. Remapping of course can cause it's own problems but you know that and probably can't convince an A5 cabriolet owing s-i-l. I don't quite follow why the sensor above the drivers door and latching unless you mean it's breaking the sequence but then you should manually be able to complete the sequence of lower or raise the hood otherwise it's not a very good manual system, how are you going to fully secure the car. If it's a 2005 next time my other neighbour is up here I can see if I can grab the Owner's Manual off my neighbour to see if there's anything in it to give a clue in the German to Chinese to English text. Just thought - you do have the rear deck lid locking tool? If you're interested this is a scanner a model or two below my neighbour's but gives a bit of an idea of what they can do. - https://www.youtube.com/watch?v=ipcyaYvjN7Q  |
| Nigel Atkins |
| Nigel
Nothing wrong with a re-map imv. I have a 2005 Volvo V70 with a 2.4 5 cylinder common rail diesel, generally known as a D5. Superb engine. I have RICA re-mapping software which takes it from 163bhp to 200bhp. It goes like stink but I don't clog it too much as there's a risk of blowing the intercooler, or so I think. The re-map is reversible. I also have VIDA (Volvo type) software running on a laptop which connects to the OBD socket via a dedicated hardware device. This was only available to the public for up to 2014 models as the main dealers don't really want people like me using their subscription only diagnostic tools (understandably perhaps but that's another debate). But VIDA gives live data and links you to suggested fault finding procedures plus how to disassemble etc. I've used it to read live data from ABS sensors and fix ABS faults, reset the heating sequence and check a myriad of stuff. One thing about older cars is that you're almost bound to have fault codes that don't want to go away but are minor niggles e.g. I get a fresh air damper motor fault but it doesn't seem to affect anything. Of course, there's a lot of stuff being sensed in real time and minor faults that wouldn't even be reported in the past seem to re-occur (or I can't be bothered to fix them....). Interesting stuff. |
| Bill Bretherton |
| Bill,
like any tuning or upgrades and improvements if they are appropriate and done well they could be better overall than factory but often they can be about cutting margins to get more performance to one area only which is fine if that's what you want and you realise what's lost and how that could affect. The problem is some seem to be done on cars that aren't even well service maintained and perhaps at high mileages and sometimes it seems without any checking of the car or even I suspect an errors code scan. Some seem to be also street corner or Tesco car park program transfers or places selling off the peg programs that may well be good but then applied inappropriately. I think it's not only with older cars like 2005 just because of their age but also their programs from new perhaps have more holes and less likely to have been patched in the middle years when these level of scan tools weren't widely available and the Dealerships might have changed hands and not see so many 10+ year old cars coming to them for work. If you think of the programs having minor senior moments that mean very little in themselves but when spread over a contact and someone actually keeping record of every instance. Then it could be it's not the fault of the item being reported but another item that is playing up but outside of the error code parameter. Like when your mate does something wrong and gets away with it but you get the blame because you were standing nearby at the time. Actually the video I put up is a poor example, I only watched the start but having watched it now I wonder if he might have been keeping a dog and doing a bit of barking himself, perhaps it looks better when the bill goes in or there was less program interconnection with the lorry. My neighbour has copied all that programming to an old laptop as it has a bigger screen but it misses something out with the connectivity but I can't remember what. His eyes are worse than mine and we both really need a bigger screen than the laptop but it was an old one going spare so no cost option. I very vaguely know the D5 and even the Yanks have it. Don't want to upset you, and it would have a lot less on it, but another neighbour's 2005 Kia Picanto loaded quite quickly and showed all green not a single history or current code on it. Willy will be pleased to know I had previously wire brushed the rust off the ABS cog wotsits and removed and cleaned the sensor heads, boy were they a pain and worry to get out, second sensor I'd discovered they only come out by levering despite being advised against such action. I put before, on my wife's 2015 VW product the scanner shows IIRC 638 data points for the engine alone, potential to seriously mix things up. All this started when we were trying to find a machine for another mate's Ford engine from 1993 that was with certian ignition bits only for a short time before they changed it. He got the lead connector cable but the Snap-On machine had been out of use for years so began the research and scank-copies of phone app programs and cheap dongle. Only for the mate to go to a chap his brother uses who plays with old race cars to be told there was nothing wrong with his engine and they all do that! You'll have to put a photo up of your machine integrating a sensor and the info you can get whilst keeping your hands clean. |
| Nigel Atkins |
| Nigel
I've changed both front tone wheels on mine, they were rusted quite badly but cleaning them up didn't clear the posted fault on separate occasions. I've also changed a front abs sensor twice - again, cleaning didn't clear the fault. All fine currently. What the car does have is a parasitic drain current which will flatten the battery in a week. I haven't traced it yet so disconnect the battery when parked at home - doesn't seem to upset the ecu's. It "goes to sleep" initially but I suspect something is switching back on when I'm not looking. Too damn complicated, aren't they. |
| Bill Bretherton |
| Bill,
you're lucky you've not got a VW start/stop they have over-complicated, over-intrusive, intertwined computer programs that can throw up all sorts of unexpected issues, especially if the battery is in a low state of charge, throw in keyless entry and diesel you could be on a longer subscription to Error Codes Weekly I wouldn't want to think what might be on an Audi! 😄 I guess things like big Mercs or big VWs with other marque badges must be worse, countless computers, programs and connections. My neighbour's 2005 Merc gives dire dash warnings, the car must go in for work immediately. I only cleaned my neighbours wotsit cogs and speed sensors because rusty wotsits was an Advisory on the failed MoT (split on the hidden part of one front ARB drop link bush, the tester must have worked for the FBI lab previously) and because I'd wire brushed the wotsit cog I thought I'd better check the sensor heads as it's all an open area and knowing my luck a chunk of rust would wedge itself on to one of both sensors causing a dash light. The scan tool purchase was months in the future, but we found no historic codes anyway later. BTW I've only been present when a scanner has been used on half a dozen occasions, I thought it'd go without saying here that I actually very know little about them and how they work, just generalities. I'd love to have a play with them but I don't own one, but you know I'd make it do as much of the work as I could, probably more than professional users, getting a multimeter out and hands dirty would mean I'd not learnt enough about them for me. I saw a video a while back where a diagnostics bloke was searching down a parasitic drain, multimeters and link wires to pins everywhere, oscilloscope trace graphs, Guy would have loved it. The chap kept finding bits others had missed and getting the drain down but not everything and gave up at an acceptable level still not knowing the last bit(s). I can't remember what bits he did find, only that it was all on VW car. It'd be interesting to compare the results you get on your Volvo with your VIDA to what the Topdon sees on your Volvo, and differences in measurements. From what I've only seen on videos, the more expensive and new scanners have much better front screen tree layouts and as a matter of taste more intuitive labelling and logos. That VCDS reminds me of seeing the sewage plant rather than the beautiful Victorian building that houses it. |
| Nigel Atkins |
| Nigel
I've no access to the main dealer system although it's used on our newer V40 as we still have dealer servicing for that. I'll ask them for a picture next time! As for parasitic drains, as I can't get the car in the garage I can't leave it on the diagnostic tool for a few days. Maybe in the summer I could leave it on for a long day. It requires longer term data logging. A meter with built in logging might do it left on a current range in series with the battery but it wouldn't identify the culprit. After the first 10/15 minutes the current falls to an acceptable level (I've tested this) but I need to know what's happening over several days. The alarm is a known culprit but I've tested with that disconnected. Could be that damper motor coming on maybe. |
| Bill Bretherton |
| Bill,
be interesting if you can get a photo of the Volvo machine I think the Skoda Dealerships keep them well hidden, perhaps they only have one machine and one technician trained to use it and he left the company last year. For monitoring and recording drain why not get a BM2 type of thing, I think you can get them very cheap second hand, you can see at what time the drain changes and by how much so you can see if it's something constant, cycling or activating for what ever reason. The time can also be compared with temperatures and weather if car is outside or other conditions that might car activations. Those silly keyless entry (and start) can be constant so if the fob is in range (or close to the spare fighting each other for strongest signal) the fob batteries also get drain quickly. battery monitor bm2 (14 Oct 2019) - https://www.youtube.com/watch?v=DJjQOUVbd9k Ctek 'Battery Sense' vs a generic BM2 Bluetooth Battery Monitor (3 Mar 2021) - https://www.youtube.com/watch?v=ODDkJ8NQPpQ |
| Nigel Atkins |
| Well, the A5 roof is fixed! All operates and no error codes.
As at least Nigel will want to know, the technician who is doing the engine remapping was using a programme called VCDS from Ross-Tech. He won't remap whilst there are any other fault codes showing and it was coming up with an error saying "front hood bar lock switch inoperative " (or something like that) He didn't want to explore further as he says it can take hours just removing trim panels etc when you don't know exactly what to look for. However as the hood bar was locking some further internet searching narrowed it down to 3 possible Hall effect sensors that could be faulty. The most likely one turns out to be moulded onto a thin plastic bracket and although its not possible to see it as the hood closes I thought that the bracket was probably just flexing too much. A stiffener shaped from a 2 x 1 cm scrap of aluminium sheet fastened behind the sensor now holds it firmly and lo and behold it now all works just as it should! |
| GuyW |
| Excellent result Guy! |
| Bill Bretherton |
| Guy, thanks for reporting back.
The Ross Tech is the one I mentioned earlier, the horribly presented program, like a young teenage computer and maths nerd has drawn it up in his bedroom as a project with little understanding or care about its presentation and ease of use. I'm surprised the mapper couldn't tie it down to the actual sensor but obviously he was doing the minimum (from experience of dealing with VAG possibly). Good of you to add a little metal to all that plastic on the car, so much for German engineering and manufacture - and one up for British craftmanship. If you son-in-law is keeping the car for more than a few months or particularly if he wants to sell it you might want to invest in a scan tool suited to VAGs. you might as well buy it yourself to save yourself hassle next repair an/or part replacement, take it out of the inheritance. Take my advice, do not be be that car when it's running and particularly on the road if he actually drops a gear to overtake. VW ought to be sponsoring facemasks! |
| Nigel Atkins |
| Nice result Guy-Well done you
Nigel-You have to stop dumping on VWs you might need a ride home in one sometime Bill--Something for you to try- Next time you're going to leave your car for the week, try locking it twice(double locking) and see if that makes any difference -I'm not sure on Volvo's but a lot of later cars have what they refer to as storage mode which is activated by double locking--Later Subaru's are bad for it, a week will flatten the battery enough to cause non starting--If the battery power goes under 7volts while cranking the ecu won't work even though the engine turns over(slowly)---A Subaru locked normally will still draw around 200ma for 15 mins or so then drops to 50ma which is still enough to drain the battery over a week or so but double locked in storage mode it goes to 0 after that initial 15mins shutdown period |
| William Revit |
| Willy, I often get a ride home in one, and you should see what I put about MGs! |
| Nigel Atkins |
This thread was discussed between 21/02/2022 and 12/03/2022
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