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MG MGF Technical - MOT Failure :(

my 96 MG just failed the mot on cat tests and HLBL not working, can anyone tell me where the fuse would be for the HLBL as i have looked under the dash and there isnt one for it, the HLBL was added as an extra i believe as they werent on the 96 MGF's

also with the CAT failure i was told it could be a landing sensor any ideas ????/


could be a landing sensor

lambda sensor
John Ponting

can't help on the fuse (if there is one) but at a pinch you could simply remove the HLBL for the retest as you correctly state they were an option back then.

Check the HLBL connector plug, when mine wasnt working this had come loose.

Unscrew the two housing retainer screws and remove the light to access the plug, if this isnt the problem just remove the light section and place some tape over the wiring access hole for the re test, if it isn't fitted it does not need to be tested.

As for fuses it would presumably run off the same fuse as the rear brake lights, as they are working the fuse would not be the problem.

The only other cause could be wire chaffing or bulbs blown, again unlikely though, do you have a tester you can put on the connector to test voltage is at the plug, if voltage is there when you press the brake pedal then the cause is the light fitting.

Chris Catchpole

Oh forgot to add, run the car hard for 20 minutes before the retest to get the CAT really hot this may get rid of any crap that is causing high levels on the CAT test.
Chris Catchpole

Yep, rag the car for a while and ask them to immediatly restest it.
The HLBL is spliced into the loom on the RHS of the car (passanger side UK), it runs off the same wire as the normal brake lights. It has multiple bulbs, so one going would not cause this problem, so you definatly have a wireing fault.

PS check the ground wire as well, this is just as lightly to have gone astray.
Will Munns

Surely the passenger sits on the left in the UK......
Patrick Beet

Ah, bugger, I do mean LHS (when looking into the boot, which you will be!
Will Munns

Automotively speaking LH side or RH side always means your left or right when sitting in the car facing forward.

Or at least it did when I did my apprentice training XX years ago:-)

Ted Newman

Thats good to know, I tend to use LHS of the engine bay to be the RHS of the car (when talking about a normal car)
Will Munns

Ted is quite correct - gets very confusing if you don't keep to this general rule.

Cat failure - as the chaps say - run the car very hard to the rev line in all the gears (where, obviously, it is safe to do so! ;o))

HLBL failure - unfortunately quite likely to be an internal wire break in the boot lid harness. :o( Check the electrical continuity of the cables with a multimeter (or get an auto electrician to do this)

Good luck :o)
Rob Bell

Rob may be right, the wiring loom to the boot often wears against the boot interior, check to see if the boot interior light is working also- if not follow the loom, my broke at the bottom wiring intersection with the main engine loom - easier to check the simple thigs first!
Simon B

Yes indeed the wire had broken again i had forgotten about this i fixed it not long back i will endevour to keep it away from the hinges when i repair it in a minute..

it is booked into rover tomorrow to check the immisions so hopefully they will sort it


Take care with MGR dealer fixing emission problems. They will probably want at least 2 hours labour + an expensive sensor and could even want 4 hours labour and a new cat.

Make sure that you request "investigate and report before fixing or changing anything".
John Ponting

failed on high level brake light?there is much debate amongst testers whether this actually is a failure! as far as i know it can only fail if the tester can prove that it is wired up (without stripping any part of the car) which makes it almost impossible to prove! it should be a pass and advice.
on the subject of emissions,it takes a long time for the C.O. to come down on the test (on "K" series engines) was it MOTed at a rover garage? if not the tester may not know this and tested it when it was too cold.

As someone said earlier if you cant fix the light simply remove it.
Other than mandatory lights........ if a light is fixed to the vehicle it must work. If its not there it cant be tested......even if it means a gap in your bootlid for 10 minutes while they retest.
D Jamieson

sorry "D", if the light is a testable item, you can fail it. high level brake lights are not a testable item, the same as front fog lights, n/s/r fog lights, reverse light and spot lights. if there isn't a "reason for failure" in the testers manual you can't fail it. the only reason that you could fail an high level brake light is if it was showing "white" light to the rear of the vehicle

apparently the oxygen sensor has gone which caused the cat to burn out... they are fitting the oxygen sensor but want 810 for all the work

anyone know where i can get a second hand cat from.....
Nick Walters

... you know who we're going to suggest don't you? ;o) The MGF Centre!!! LOL

810 quid??? OUCH! A very painful discovery that Nick - sorry to hear such wallet bashing news :o(
Rob Bell

got a cat from midland mgf for 120 delivered and thanks to S/S nuts i shoud be able to fit it myself
so with the oxygen sensor fitted from rover at about 200 hopefull it will be about 300 - 350 in total

Nick Walters

Nick, 810 is extortionate. I got stung 460 for replacing the sensor and a track rod end followed by an MOT by an MGR dealer.

Thinking about it again, 460 + supply & fit CAT could get towards 700-800. My dealer charges 65 + VAT for labour so it adds up rapidly.
John Ponting

Oh i just cant resist it.

I hate MGR.

This story is so typical i have heard and experienced so often.

Once, MGR wanted to charge me 300 notes to reset my ecu out of "limp home mode" back to normal state. ( which i did myself be disconnecting the battery for a while )

They wanted 100 pounds to take my cat by pass tube of and replace with the CAT I supplied them with ( oh.... and they wanted me to wait 3 weeks )

Then they wanted near 600 quid to change a gear change cable ( which i did myself in under 3 hours ).

Then they wanted to 150 pound to investigate a rattle in teh engine bay ( alternator bolt had loosened )

Then they wanted 15 pounds for a new bolt ( halfords sold me one for 10 pence!!! )

Needless to say they didn;t get a single job from me.

I hate them. I hate them. I hate them.

I cant believe that a company who knows SO little about MG's actually sells them.

And lastly, while i rant, what kind of disgrace to the MG badge is the new MGZT-T DIESEL?????? Since when did a diesel estate deserve the marque of the classic british sports car??? MGR have a lot to answer for!!!!!


Garry - you don't have to use the franchised dealer network to get your car serviced. I don't. And much happier I am as a result! ;o)

Regarding the ZTT diesel - what's wrong with this? Heck, I'm even considering getting one (to replace our venerable 75 saloon, I hasten to add)! Yes, okay, I'll probably want to go for the 190 V6 version, but 40mpg for a large sporting estate car is difficult to argue against. Would you rather all the money went to BMW instead?
Rob Bell

if youb want something to get your teeth into a small job like changing the oxygen sensor they have charged me 336.31 of which 160 is the part W***ERS.

i cant wait till my MG is sold and i can get an audi or something more reliable...
Nick Walters

ZR diesel has been around for ages and is selling well

ZR Express can also be had in a diesel - this is a van and is also selling well. That's right, an MG badged diesel van.

ZT-T has been around for ages - this is an estate car, again selling well.

With these three cars MG have successfully broken the mould, there is no reason to think that a ZT-T diesel wouldn't also be a good seller.

The more cars MGR sell the healthier thier balance sheet will look. The healthier thier balance sheet is, the more cash they will have to develop new models which fit your blinkered view of what an MG is and should be. So, regardless of your feelings towards these cars, surely if the end result is for example a new midget or an extreme TF, surely it can only be good?

Also, selling diesel MGs targets a new customer base, these people (hopefully) will remain loyal to the marque and this too can only be good.

For these reasons i have no qualms about the Streetwise, the CityRover, the 1.6 versions of the F and TF, the smaller capacity R45 or any of the cars in the MG / Rover portfolio - the more they sell, the better my chances are of getting a new MG that more fits my requirements in the future. They may not be quite my cup of tea, but others will like them, buy them and in thier own way contribute to the genesis of the next generation of MGs.


I couldn't have summed it up better myself Smiley.

Tony Harrison

I think you have mis-understood me.

I have no problems with MGR making poor cars suitable for the over 50's. Really. I just have a problem with them badging them as MG's. Thats what the ROVER marque is for.

Next thing you'll be telling me is that the MG Maestro was a good move......... Nothing wrong with a maestro. If you like that kind of thing. Just weren't an MG.

An MG car should be something to be proud of. The pinnacle of what rover can produce. Blinkered? Well, maybe. But year after year rover promise something special..... Extreme TF? I'm gonna grow a 3rd arm before they are in the showroom. In the original press release of the Z cars, they ranted about a 450 BHP ZS. Wonderful. Where it is? Where can i buy the MGF Supersport?????

And another thing.... when will MG take the lead of various other companies ( mercedes, BMW etc etc ) and get aftermarket companies to increase the performance of the car before its sold? What a wonderful idea a "Turbo Technics mgtf" would have been in an AMG Merc kinda way.


well it passed finally yay..... everything is cool now, still selling it...... need a change
Nick Walters

This thread was discussed between 29/07/2003 and 07/08/2003

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