Lost led breaklight/light on trunk right side

[Pljaa]

My Mercedes E class coupe 350 cdi C207 (2010) rear right tail led light (on the boot lid) is not working.
I have tested the lamp it's ok. Anyone know what fuse or reley that might be the problem ?

 

[EmilysDad]

is it a tail light or brake light? Front side light & rear tail light are likely to be on the same fuse, so if the front right side light is working it's unlikely to be a fuse. If a brake light & the other side is working, the it's probably a break in the wiring to the brake light that's not working. You need to check for voltage at the socket

 

[Pljaa]

The problem is all light as brake, reverse and tail light on the trunk right side. All other lights on both sides front and rear are ok. I think I need an expert to check if it's a broken wire. Do you know if there is any repair parts from Mercedes or others to replace the wire if it's broken ?

 

[EmilysDad]

...... Do you know if there is any repair parts from Mercedes or others to replace the wire if it's broken ?

I don't know, but you could ask at MB, MB do seem to do repair looms for reoccurring faults/problems.

 

[mioba]

As mentioned check you have voltage at the light connector, check all the prongs are clean and making connection with the light fitting, a shot of contact cleaner is good.
Take it from there.

 

[Pljaa]

Hi Mioba and thanks for your ideas on this problem. I have voltage on the connector and gave the lamp and the contact a shot of cleaner. Still not light so I have bought a new and tested it but still no light, but when I test on left side all lamps light. How can that be possible ?

 

[Pljaa]

Have tested the contacts on the trunc on both sides with meter testing both voltage and cable break. See enclosed pictures and description. The conclusion is no voltage on the defective right lamp on pin 1 on contact but 3.17 on the left side lamp on pin 1 that is OK. Can any tell if its a fuse problem or any other issues. Also tested defective right lamp on left side and then its ok.

 

[Botus]

My fathers E class W211 just died on all electrics on the boot lid - I would check if you have number plate lights..

investigating this common Mercedes failure mode on my fathers car - the wiring on the left boot hinge its clearly designed to be stressed and snap it like a carrot after x occasions of boot opening. The loom is so constrained and securely fixed, alongside a badly made hinge trim cover, every single bit of boot lid movement stresses one 5mm area of the long loom until one larger wire fractures.

I repaired the fractured brown thicker gauge wire, then relocated the looms position so that

1) the previously high stressed area is no longer subjected to movement
2) changed the arc the loom moves through as the boot lid operates from 1cm high stress kink to a gentle 10cm circle (noting the spare 8" of loom doing nothing !!!!)
2) modified the hinge trim allowing the loom to flex without the designed to kink stress razor Mercedes lock in at build