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MG Midget and Sprite Technical - full beam not working

Hi folks,

hope you can help, well you have not let me down yet, anyway, all the lights on my car are working fine, except when I push indicator stalk forward for full beam my headlights go out! arggggggg! any ideas, it's a 1974 RWA I guess it's the original stalk, I'm sure the wiring is correct, where is the best place to look first? how does the main beam work?

cheers Jack.
Jack New Forest

Hello, Jack -

I once inadvertently disabled my dip beams by pulling a wire off the switch while refitting the steering column surround. Maybe you have a similar issue!

Best,

-:G:-
Gryf Ketcherside

Hi G I have the cover off the switch at present caan't see any loose wires, but I'll keep looking!

cheers Jack.
Jack New Forest

check for power at the purple wire (power from the fuse box to the switch for main beams). It is powered on regardless of key position.

if that has +12V, then check the blue / white wire (connects the switch to the headlights) and it should have +12V when the switch is "on". If not, then the switch is bad. If it does, then check the connection in this wire located in the front, between the front splash panel and the RH fender where it splits to the two front headlights.

If there is power all the way along, then you've got two burned out filaments (no need to check the ground, because if it was bad the dip beams wouldn't work, as they share it).


hope this helps,
Norm
Norm Kerr

A quick check is do the high beams work when you flash them ? If they do then it clearly isn't the bulbs. In which case study the position of the little contacts inside the column stalk switch. They can get tired and bent away so that they don't make contact when the stalk is pushed forwards.
Guy

All good stuff but really electrical problems are easy to solve if you take a logical approach

I think that the power to the switch is via a blue wire and that must be OK otherwise you would not have any dip beam.

So you need to check that the main beam bulbs (lamps) are OK this is very easy. At the headlight you will find some connectors There will be a blue/red wire and a blue/white wire.

The blue and red wire is the power for the dip beam and is obviously working the Blue and white wire is the power for the main beam You can simply swap these 2 connections around and see if the dip beam still works? Now switch to main beam and see if that works. If the situation is still as it was hen the lamps are OK and it would be a far suggestion to check the switch as described by Guy. If however you now have one headlight working on main beam and one on dip then it would appear your bulbs a poorly!
Robert (Bob) Midget Turbo

Hi Guy no they don't work when I try the flasher, they are new lamps so should be good, I suspect the stalk is dodgy!

Jack.
Jack New Forest

OK Bob, going to try your idea, I know what you mean it should be elimination and trial and error, here goes.

Well swapped the blue and white and the blue and red, switched on lights, headlights were brighter so assuming that is main beam, but when I pushed the stalk to main beam lights went out, so I think both lamps are good in dip and main, got to be the switch, do you think?


Jack.
Jack New Forest

Yes sound like the switch as described by Guy the only other possibility is a loose wire somewhere. Coming from the switch you will find the 2 wires blue/red and Blue/white you can again swap these 2 around to see if the problem changes around or if you can use a meter simply measure both for 12 volts when selected. Blue/white is high beam
Robert (Bob) Midget Turbo

My point was just for simplicity - you can sit in the car and flick the column switch up for flashing the headlights lights, and down for switching to main beam. If one worked and the other didn't then the fault would lie with the switch and would probably be a bent contact spring. If neither works then the fault is with the wiring ( blue/ white wire for main beam), or with the bulbs themselves. Yes you can check the bulb filaments by swapping wires over, or swapping bulbs over, but my suggestion doesn't require even that minimal level of intervention.

So, as they don't work on either flash or main beam it is less likely to be the feed to the column switch itself. The fault is either with the blue / white wire to the lamps, or with the bulbs. I would suspect the connection inside the column switch where the blue/white wire is "riveted" to the terminal. Alternatively,it is now time to remove the headlamp rims and check the supply and the bulbs within the headlamp bowls as Bob describes.
Guy

follow Guy and Bob advice

and following on from it -

if you swap the wires and main beams work then obviously check all of the main beam wire and connections

but pay particular attention to the twin connector than brings one wire in from the switch and has two wires going out to the two main beam filiments

it's usually situated behind the rad grill

if the wire, bullet or connection going in is faulty then obviously it will effect both supplies going out

because of its location the bullets and connector can get furred up so all need cleaning

I tried replacing some of my bullet connectors with new ones but they were so poorly made it was better to clean the old connectors

Nigel Atkins

Jack,

Am I correct you have just fitted new head lights ?

Did they all work previously ?

If so it could be just bad connectors - there is a major junction of loom wires at the right hand side of the dash against the A post and again around the grill area as Nigel has pointed out.

Just check the wires for power from the r/h side of dash connectors and see if that has power to blue/white then if o.K move to front first bullet and check there etc.

R.
richard boobier

Thanks Richard and Nigel, and all the others Guy Bob etc. I shall continue my investigation today, I won't let it beat me, Oh! I should not have said that! could be at it forever Ha!

cheers Jack.
Jack New Forest

Well don't laugh lads and Lassies ( that's you Rachel), I've been at it all day, checked all the connections, still no joy.
Getting worried now, because I need it working for my MOT next week!
Somebody mentioned checking I had power to the blue and white wire 12V, I have borrowed a friends Multimeter but not sure how to use it to check the power to the wire, do I need the light switch on? do I put the stalk forward? don't know what I'm looking at on the Multimeter! when it comes to electrics I'm a novice!
And just to make my day worse, my horn was working, now it's not! checked the purple wire I don't think it has power! I have checked all my fuses they look OK, So here is where I am! I have a lovely Pear tree in the back garden, and the rope is hanging quite nice need I say more Ha! Ha!

I'm all wired out!!!!!!!

cheers Jack.
Jack New Forest

Jack put a sharp knife in your back pocket just in case you remember something to help

did you undo and clean all connections then check they were secure and protected after?

depends on multimeter but you'll need to set it for the range that covers 12v to test a live 12v supply

er I'm probably not the best to describe a multimeter as I don't have just a chep continuty tester that bleepers

yes you'll need the the lights switched on and stalk on high beam

beware you're working on live supplies carefull where you're poking around

the horn will only probably be where you've fouled a poor connection and you'll find it withe same process you're using to sort the lights

some times these jobs are easier done with the help of a willing assistant to wingle wires to also find brakes or loose connections
Nigel Atkins

Thanks Nigel, I've taken the rope down, because I want to go for a run in the midget at the week-end, weather is too good to miss, yes I agree I've got amate who was an instrument tech. so he is my next port of call tomorrow, see if he can spare an hour, I think your right it's something stupid and simple (a bit like me) and we will crack it.

cheers Jack.
Jack New Forest

Good idea Jack sometimes you can be too close to a problem to see it fully

and you're right about having the correct driving to repair ratio

BUT

I never said anything about taking the rope down,

you'll want to look at that rope after starting the next "simple", "quick", "easy" or "5 minute" job
Nigel Atkins

Hi Jack

I wanted to suggest you need to seek help if you do not feel competent to use a simple meter so I think that is probably the best idea you could have.

Your mate being an Instrument Tech should eat this problem for breakfast and soon have you sorted.
For information I served my aprenticeship as an instrument tech before going to uni and becoming a full blooded Instrument/electrical engineer. didn't do me any harm

Funnily enough in the mid 70s I became a site manager for a construction company and had the pleasure of working in Hampshire. I help build and commission the Cyanamid chemical plant in Gosport all those years ago, it would be a huge coincidence if your mate worked there?
Robert (Bob) Midget Turbo

By the way this may help you to understand electrical use

http://is.gd/HWmFFq
Robert (Bob) Midget Turbo

Thanks Bob, my friend worked with me in Esso refinery Southampton, I was in Process making Petrol/Jet fuel/Gasoil etc. he looked after our instrumentation, and now we are in the same car club, he has a lovely 1947 Jag.

cheers Jack
Jack New Forest

Jack

know it well I was also working at Coryton when Mobil upgraded their cracker. I have since worked or many years at our 2 local refineries ar Killinghome
LOR and Conoco.
Robert (Bob) Midget Turbo

Bob Nigel guy etc.

well folks I've cracked it, simple testing of power to wires, found no power to blue white wire on stalk switch looked melted and poor connection, so looks like new switch getting ordered, if it's the original it's lasted well. thanks you all for your help, I'll let you know if we are back to normal when I fit new stalk switch.

cheers Jack.

Bye the way Bob, I've taken the rope down, but still have the knife in the back pocket ha! ha!
Jack New Forest

Jack

some new column switches have been known to be of poor quality

so if there's anyway of your mate repairing your existing switch then do that instead

PS what about the horn?
Nigel Atkins

Yeh! I've fixed the horn, so just got to get a new stalk, If I get the original lucas one it should be OK yes?

cheers Jack.
Jack New Forest

Jack,
I doubt that you would find a genuine NOS Lucas one these days.

The original one on my car lasted 38 years. The two replacements since then both looked like the original, but managed less than 2 years each. I have since added light relays so as to reduce the current through the switch and hopefully get a longer life from the latest one!
Guy

This is a Lucas but WITHOUT hornpush on stalk

I've bought bits (not switches) from here before and they've been OK

http://cgi.ebay.co.uk/MGB-Sprite-Midget-Lucas-Column-Indicator-Switch-37H8050-/190512517292?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item2c5b6e50ac

BTW - what was wrong with horn?
Nigel Atkins

It might say 'Lucas' on the shiny new box, but where was it made?

Dave O'Neill 2

Yes good point but are the new duff ones from Lucas (I don't know)?

These are genuine Lucas as far as I know and I don't just mean the box

Note, not claimed as NOS though
Nigel Atkins

Specifically, the fault I have had on 2 sets of these replacement ones is that the terminals for the cables are made from what seems to be a very brittle form of "brass". Where the terminals are connected, the brass "post" is splayed over to make the connection, but this is where they have both broken. The other problem is with the small contacts themselves which are mounted on thin spring-like leaves of metal which looses its springiness so that with time the position of the contacts changes.
Guy

Nigel I'll have a look at that site for a new one, my horn push is on the steering wheel, it was just a loose connection.

I used to love my Frogeye so simple, indicator switch on dash dead easy, dip switch on floor for foot operation dead easy, the more I have Classic cars the more I go back to older cars, keep it simple!
I'm building an Austin 7 special at present, there is probably about 10 wires!

Still I'm learning quickly about Midgets, thanks to you guys.

cheers Jack.
Jack New Forest

Hi Jack,
What sort of 750 Special? I used to have several at an earlier stage in my life! Photo?

Guy
Guy

Guy that sounds poorly made alright same as the one I got for my Triumph about 4 years but I can't remember it being a Lucas, were yours?

Jack, I've sent the supplier a question about reliability of these units and asked where their Lucas one was manufactured to help you, me and others establish a decent source and item

The one I have on my car looks a little out of shape but whilst it still works I'll keep it, be interesting to see if I changed it whether the headlights got brighter by the change - headlights on mine are already bright though

Oh, the horn pencil can be put in upside down there was a mention of this somewhere if I find it I'll post it
Nigel Atkins

Nigel,
Not so much poorly made as poor materials. The last one that failed after 2 years came in a Lucas green and white box - I know it did because I have some old used spark plugs stored in the box. Not sure why, but I always keep old used spark plugs "just in case". In case of what, I am not sure!
Guy

Guy, I have a old ruby 1937 6'9" chassis which I am rebuilding almost finished suspension, I used to have a super accessories body, but it was for 6'3" chassis, so I swapped with a guy and have a decent hand built body ally over a tubular frame,
I'll dig out some pics. still got lots of work to do on the car, geabox is OK, I have the engine on my bench just waiting on some gaskets, it's a two bearing which are supposed to be better,
I'll get some pics up tomorrow, I play drums in a rock n roll band, our gig tonight was cancelled (painting the pub) so I'm off out for a pint to watch another band (busman's holiday I guess) talk to you folks later.

cheers Jack.
Jack New Forest

Jack,
I started out with a 1935 Ruby - that is what I learnt to drive in. Changed that for a Pearl cabriolet (1934 version, I think) Then I bought a lovely Cambridge bodied special which I really wish I still had! The Cambridge was very low and pretty fast with a fairly well worked on engine. Good for over 90mph anyway, which is pretty fearsome in one of those things! I do remember it had no starter motor,it started on a handle, or more often just by pushing it down the road and vaulting in over the back. I was a good deal younger in those days!!

The 2 bearing crankshaft engines were supposed to rev better and be less inclined to break crankshafts which is sort of opposite to what one would expect.
Guy

learnt to drive in a 1935 Ruby - wow I'm starting to feel young

message below came through, if you don't want it and it's still there when I remember (probably this time next month) I might buy for stock that way I can look at it and see if I can improve it or more likely bust it

'Hi Nigel

These are UK Lucas ones and I have never heard of this or had problems with any I have just sold, but I have just sold my last one and I have heard that Lucas will not be making this one again. I may have one more in stock and if so I will put it back on the site Monday.

Best regards Duncan'

Nigel Atkins

"learnt to drive in a 1935 Ruby - wow I'm starting to feel young"

- Nigel, it wasn't exactly new at the time! Although come to think about it it was younger then than my present daily driver Sprite is now!
Guy

Guy what can you tell us about crystal radios and headsets in a bowl so others could listen

:)

you've seen so much, the birth of internet,



television,



radio,



electricity
Nigel Atkins

Nigel thanks to you, I think I have just bought the last Lucas stalk, if we are both talking to the same man, I'll let you know how it goes.

cheers Jack.
Jack New Forest

LOL Nigel - I believe that is the appropriate modern expression.

Funny you should mention electricity - some years ago I did some design work on the grounds of the first private house in the country to have installed electricity.
Guy

Guy if only I could remember I should know which house that was as I'm sure I've visited the place (assuming it wasn't yours)

Jack glad to hear that, I just hope it's a good 'un now as I'll probably get that other one if it's about Monday

but if I do that it'll be certain that they aren't good 'uns, oh well I can always keep the present one just in case
Nigel Atkins

This thread was discussed between 06/04/2011 and 09/04/2011

MG Midget and Sprite Technical index

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