Light not working, MOT just around the corner

S

shadow1993

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Hey, Just after a bit of advice...

my front left light isn't working, Not high beam or dipped beam, just the tiny light that will make me fail my MOT.

I've checked it with a multimeter and its getting 0.3v not 12v. Traced it back to the main headlight connector block and by using a mirror i THINK i found the wire that is supposed to feed the bulb in question, but that is also only getting 0.3v

My Autolights randomly throws up an error but the book just says to take it to an audi garage.

Now i know its not viable to trace back a loom for a broken wire, so what are my other options to get this light to work?

Any help is greatly appreciated.
Thanks for reading.
 
The sidelight bulb is a nightmare to change. Remember doing it on the wife's car. Unless you have girl or midget hands it will take some time. I would mention it to the MoT tester/garage and get them to change it during the test. Save shredding your hands to bits...
 
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Have you tried just renewing the bulb? Is there any chance you are measuring on the -ve side? If not, PM vehicle details and I'll try to help you out.
Hi,
Yes i tried the working bulb in the non working side, also tried the original bulbs too..

Well i was measuring both terminals for the bulb, so i assume that's correct? What details do you require?

Thanks
 
The sidelight bulb is a nightmare to change. Remember doing it on the wife's car. Unless you have girl or midget hands it will take some time. I would mention it to the MoT tester/garage and get them to change it during the test. Save shredding your hands to bits...

Ive had it out a few times... i find levering it with an electricians screwdriver helps a bunch.. its not the bulb though.
 
Hi again,

The only way to do this to satisfy an MOT (such that it actuates via the switch), is to splice off the right hand front sidelight power (which originates at the body ECU above drivers footwell). This may cause a dash error as electrical load won’t be to spec, but it would work. I don’t recommend you do this.
The correct way is to trace/renew broken power wire. If you want to attempt this I can provide PIN data etc and help you out. This is not advised if you are not confident working on modern vehicle electrical systems…a small mistake can be costly.
 
Hi again,

The only way to do this to satisfy an MOT (such that it actuates via the switch), is to splice off the right hand front sidelight power (which originates at the body ECU above drivers footwell). This may cause a dash error as electrical load won’t be to spec, but it would work. I don’t recommend you do this.
The correct way is to trace/renew broken power wire. If you want to attempt this I can provide PIN data etc and help you out. This is not advised if you are not confident working on modern vehicle electrical systems…a small mistake can be costly.

Problem with tracing the mistake is the wires are very long and it could be broken at any one of million locations... :(

What if i was to run a wire from the right hand side light to the left?

Assuming im able to then make the lights waterproof once again?
 
Problem with tracing the mistake is the wires are very long and it could be broken at any one of million locations... :(

You can volt drop test the power line to trace fault fairly easily, but I accept access and tracing loom can be tricky.

What if i was to run a wire from the right hand side light to the left?

You can do this, yes. This was the splice mentioned in previous my reply.
 
You can volt drop test the power line to trace fault fairly easily, but I accept access and tracing loom can be tricky.



You can do this, yes. This was the splice mentioned in previous my reply.

Not really an expert at car electronics and knowing my luck as soon as i start dismantling engine bay to access loom i will just break more old wires.. :/