rs1991

Hello!

My right number plate light stopped working, so it took it our for inspection. The bulb looks okay, i had a problem with bad contacts before, but now just moving it a bit does not do anything. The light in the cluster for blown bulbs did not show up all this time! I measured 12V with multimeter.

Then I took the working left license plate light out and swapped the bulb to the right side. The DIS warning came on and now there is only 0.5V on both sockets, and both lights are gone

Is there a fuse that I can check? I can't find any related fuses in the manual.
Tips please...

am_ver

Why not replace the entire housing and try?

BP-Hatzer3

The license-plate lights are not fused, they are controlled by the comfort-module.

Turn off ignition, insert 2 new bulbs and license-plate light would work at next engine start.
If u have only 1 non-working light, comfort-module turns off power for both.

mystrodo

The Audi engineers must have been out of work that day and needed to create something even if it didn't make sense or.... maybe it does..it sends another Audi owner to the shop if they don't know the info you provided..I sure didn't. Thanks BP-H

BP-Hatzer3

I had the same problem with a number-plate LED, which wasn't working.
I replaced the LED and at next engine start both LEDs were working till now.

am_ver

hmm... idk, my friends 05 C6 had only one of his license plate working and the other one was burnt out. So effectively u could only see half of his license plate numbers. I put in my old bulb and now both are working. Maybe his car didn't come with the comfort module.

rs1991

I've also had only one working for a couple of days and didn't even notice it, because there was no warning! The warning came up later, when I took the working one out.
I tested both bulbs on 12V power supply and they work. I fitted them back, used VCDS to reset the error, turned off the car and started it again. There is still 0V - no power on bulb housing

BP-Hatzer3

Regarding the wiring diagram the number plate lights are directly connected to the central interface for comfort-system J393 without extra fuse between the interface and the lights.

The fuse for the interface u can find on the fuse-holder ST1 (black, trunk right-sided, SF7; should be a yellow 20A-fuse).

rs1991

Thanks BP-Hatzer3, I checked it right now and it's okay. Module 46: Central Conv. is also seen on VCDS and is still throwing the same error. I tried clearing DTCs several times and started/stopped the car.

That's so weird! It may be possible that there is a bad contact between housing and bulb holder - hapened to me before, a little reposition and it was working! But not now...

rs1991

Still just walking in the dar and this warning light is really driving me mad. Anyone has a diagram of Comfort unit output pins? So I can see where the output voltage for number-plate lights is?