One rear light doesn't work. Bulb okay and brake light does work. Any ideas?

[ross62]

54 plate Audi A4 Cabriolet with a non-functioning rear light

Hi,

I'm new to the forum and looked for anyone who had experienced similar problems. No luck.

After four years of ownership the passenger rear light stopped working. Bulb and a spare both checked out okay and both illuminated correctly when pressing the brake pedal, so power as far as the bulb. I have checked continuity from the bulb holder back to the nearest connector and all seems fine.

Is there anything else I can check without stripping down the car? And does anyone have access to a wiring diagram/ workshop manual for the electrics?

Many thanks if anyone can shed light (bad pun, I know) on this problem.

Regards,

Ross

 

[paul20v]

Hi
so is the side light that doesnt work ?

 

[scott b]

bad connection on the buld holder?

 

[Woorlord]

Had a similar problem on o/s rear brake bulb - worked then did not.
Wiring to cluster was good, changed bulbs many times but then found old bulbs were still good when tested out the car.
Eventually found that the connection between the two metal strips which eventually go to the bottom tip of the bulb was intermittent.
After many hours of testing on my workbench with a 12V PSU and DVM I resorted to soldering copper wire between the two metal strip parts - actually cut out a section of the metal too.
Not the best metal type to take solder but eventually managed it with a bit of scrapping on the respective surfaces.
Since this repair never a problem.

Cab wiring diagrams below.....