CLS W219 3rd Brake Lamp Warning

[siremastimus]

Hi

Have a "3rd Brake Lamp" warning come up on my display every day now - had car serviced at Wayne Gates recently who checked the lamp and said was fine but it keeps popping up - does anyone know a fix for this or is it a case of replacing the lamp anyway?

Is it right that you have to strip out all the back seats to get to it!

Don't suppose there are any guides around on doing this - did a search but couldn't find anything

Thanks All

 

[Paddcomp]

Possibly not the same but I had the "3rd brake light failure" error and no light. Turned out to be a wire shorted somewhere (I didn't fix it so not sure where).

 

[siremastimus]

Mmh thanks, does anyone know how hard it is to swap out this light - do the rear seats have to come out?

 

[Steve_Perry]

Your problem will be a fraying cable that's in the harness that travels on the near side boot lid hinge.

Mine went a few months back, first the 3rd brake light failed, then the number plate lights failed finally the boot lock mechanism failed to open electrically (the boot would open mechanically on the emergency blade key).

Turned out I had a couple of chafed cables, one being an earth which caused multiple failures.

S.

 

[bumbiuk]

I have third brake light failure. Replaced the light (PITA) but it is still dead. Not sure that harness by the left boot hinge would be faulty, as the light id at the bottom of a rear windscreen and the wires to it can not reach it via boot lid. There are only wires for number plate lights that are ok. Any help welcome. Also replaced the A relay in the boot, but it has nothing to do with the third brake light, which was suggested in one of the threads. I am desperate to fix it. CLS 320 CDI 2008

 

[Borys]

On mine it was only the light failed
Swapped it and all is in working order
Bit of a challenge to do it thou

 

[andy27168]

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