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MG Midget and Sprite Technical - Another mystery wire

Hi guys
Mystery wires have been done to death but here goes, this one on my 1500(single and covered in extra black plastic sheathing) seems to be factory and runs from under the dash thru a grommet in the firewall, down beside the gearbox, along under the car and runs up thru a grommet into the boot where it lies lonely and unterminated. Needless to say the dashboard end was also unterminated. It isn't the wiring to the fuel gauge is it?, because this is a separate wire in the main loom to the tail lights etc.
Any help would be appreciated. All electrical functions to the rear are operational including the fuel gauge. It's acccuracy is yet to be determined.
R W Bowers

What colour is it?

Is it actually part of the loom anyhwere, or is it completely separate?

If the latter, I would suggest that it has been added by a PO.

If it is original, the colour should identify it.
Dave O'Neill2

is it purple?
If so then I assume it is for the boot lamp via a small switch?
Bob Turbo Midget England

If it runs under the car, on its own it doesn't sound like an original loom wire as these run bundled together inside the car. Maybe someone has had problems with the fuel gauge and this was added for a while and then abandoned. Or maybe a feed for a CD changer, car alarm, fog light or some such extra at some time?

What year is your car and was it registered new in oz, or imported at a later date?
Dave O'Neill2

Thanks gentlemen
in order:
the wire is black with a black sheath
the car is a 1979 model registered in england and imported to Oz by it's owner in 2006
no it's not part of the loom
the boot light wire is indeed purple and this works well

I am very familiar with all the wiring codes for this car as I have completely stripped and refurbished the loom, switches and fuses. all connectors are now modern spade clips. This was necessary due to corrosion and "black wire syndrome" on some earth returns. She now has 12 fuses 6 relays, electric fan, windscreen washer, and provision in the loom for extras including electronic ignition ( a kit from Denmark would you believe at approx $40 aus.)
The indicator switch had to be rebuilt, I now consider myself an expert on these things, however I can't help with the earlier models but suggest some work on spring tension etc may help.
The things we do to get reliability, especially in our hot climate, the electric fan is mandatory.
As to this wire it has to be an add on perhaps for the fuel gauge, I shall retain it just in case.
Cheers lads
R W Bowers

Well, logically, if it is black perhaps it was added as an additional earth wire if a PO was having problems with poor earthing on one of the rear lights.

there’s a chap on here, Tim Lynam, that could do with your advice on the late indicator switch

look on here for the thread - Indicator Not Stopping On

yeap black with black sounds like an add-on as black would be earth

the later models had more stuff put on them as standard and '79 is getting towards the very end
Nigel Atkins

The reason I enquired about the age and origin was that the last 1500s in the UK had to have a rear fog light.

I don't know if wiring looms were updated for this, or whether they were just added on.

I'm not sure if this could have been a dealer retrofit.
Dave O'Neill2

Hi gentlemen
Re Tim's problem I had a quick look at this thread.
The reason I have "relayed" everything on my car is to take the current load off the switches thereby lowering the heat generated across the contacts and sparking due to switching. It is the heat which destroys the switches. I rebuilt my flasher switch assembly after it partially disintegrated during removal of the steering column. I had to fabricate an aluminium cover to hold the tension spring in place and fix this with very small self tappers and epoxy.
In the process I derated the spring because the original was far too stiff and was partially to blame for the failure. the result is better than new and, I suspect better than any switch available now.
When reassembling use some contact grease or similar to reduce friction.
While your at it check all the solder joints for "dry joint" syndrome, easily fixed just resolder them.
Pardon my ignorance what is a "PO"?
FYI the VIN is GAN 6 229253 G, colour Oatmeal??(I would have said cream) and she is no 246 in the last batch of 500.
Well enough for now
R W Bowers

PO = previous owner.
Dave O'Neill2

thanks for your reply about Tim's switch - I've cross posted it in his thread to double the chances of him seeing it

Nigel Atkins

If it had been put in by the factory, then it would not have been black because as already noted, that means "earth", and so there simply is no need to run one of those for any distance in a car that is pretty much made of "earth" (though it is common practice in a fiberglass vehicle). ":o)

Regarding whether it had been used for a rear fog lamp, the "proper" color would have been red/brown (wire from the switch to the rear fog lamp), if from the factory. Possibly it could have been red/yellow if they had just used a front fog scheme, but most likely red/brown.

If it was a dealer fit, then the color could have been any color at all (though, I bet that if there had been a factory "kit", it would have come with a colored wire).

And, for those keeping score at home: a front fog light ought to be colored red/blue (fuse to switch) and red/yellow (switch to lamp)

Norm Kerr

Hi guys. Rear fogs were a UK requirement on all cars resgistered on or after 1st April 1980, ie V regd (Aug 79 on)

As midget production ceased in Dec, no cars were fitted with rear for lamps from the factory so the loom never had provision for them. The last MGB's did have oe rear fog lamps as production didn't cease ubtil the end of 1980.

Maybe some cars were dealer fitted with such lamps if registered after that date or if a new owner wanted them.

Incidentendly the correct lucas colour for rear fog lamps would have been light blue/yellow.

Would suspect your wire has been added by a previous owner.

Hope this helps.
SR Smith 1

SR useful and interesting info there

that information should be added to the bank that someone said they were compiling
Nigel Atkins

I worked at a BL dealer in the late 7='s, remember all this stuff, sad init?
SR Smith 1

not sad but exactly what's required, factual information from back in the day before it's forgotten or lost

sad is when you can't remember or not sure and it's about something quite recently
Nigel Atkins

I must be getting old, lots of these cars getting restored now are those I pdi'ed back then!

Lots of great stories about BL quality control as well lol
SR Smith 1

Correct me if I'm wrong, but weren't the last 500 Midgets all black?

b higginson

Or was it the last 50?
b higginson

last 500 according to Terry Horler's book
Nigel Atkins

What was that then, homage to RR, both black, when they were both dead?

It's a shame the last spridgets were Triumphs. :)
Lawrence Slater

afternoon morning whatever guys,
Thanks SR Nigel etc. I thought the black paint underneath everything was panel undercoat where guards etc had been replaced after battle damage. The car has at least three coats of paint on it in parts. so logically she was black Hmmm.
The fog light wire (definitely black with a black sheath) makes sense as it had a female spade clip at the front, clip missing at the rear, the wire simply rolled up and stuffed into a crevice in the boot. I do have 2 small blind grommets filling approx 6mm holes on the left/passenger side above the rear bar (in line with the rev lamp), is this where the fog light went?
Currently I'm removing copious amounts (half a bucket load) of fibreglass and bog from the bottom rear of the boot and replacing with metal. Please suggest this repair method to any panel beater acquaintances you may have. I have to say that I think the art of metal repair has been lost to the current generation of so called tradesmen, if it can't be unbolted and replaced or filled they will write off the car. In their defence I have to say that the thinner higher strength steel used today is very difficult to repair.
I am using approx 1mm (Passivated? has a thin zinc coating, not galvanised) mild steel to repair all of my holes, MIG welded (gasless works just fine with practice by the way) and then undercoated with a spay on rust treatment/primer then painted then underbodied if required. Whew, hopefully goodbye rust hello regained structural integrity and thanks for the roadworthy (MOT).
Just going out to cut, shape and weld some steel.
will send photos if I can get the puter to find the camera new technology bah humbug
R W Bowers

Rear foglight should either be mounted centrally or to the righthand side, not on the left.
Dave O'Neill2

Hi All
I will now attempt an upload may the force be with me
R W Bowers

Hi Dave etc
OK so what are the holes for? Hmm
Never mind it seems my photo upload didn't work sorry will try again
PS I'm new to this please forgive my ignorance, if the photo doesn't come through I would appreciate some technical assistance
R W Bowers

If you're having problems uploading the photo, it may be too big. You'll need to resize it and try again.
Dave O'Neill2

Hi Dave
excellent advice, pic is 2.2Meg obviously too big.
R W Bowers

6mm is too small perhaps for putting in some sort of cavity protection unless you find a load more all over the car

who knows what previous owners got up to with the car perhaps there was something electrical in the boot (trunk?)

photos can tell a lot (sometimes a lot of lies when the car is being sold)
Nigel Atkins

Hi Dave
are you up to watch the superbikes mate?
the holes were a suggested mounting point for the supposed fog light, if you say it was on the drivers side then something else was mounted here, maybe for the yanks
R W Bowers

This thread was discussed between 21/02/2012 and 26/02/2012

MG Midget and Sprite Technical index

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