w164 ML faulty door mirror light unit

[Bruiser]

Hi -

The drivers side indicator in the mirror stopped working and I got a warning message on the information system.

I replaced the sealed unit but the fault remains. I checked the new part and it works fine on the passenger side. To add to the mystery when I put the new unit back on the drivers side for a second time it all seemed to work. .. until the following morning.

Seems like I have some sort of intermittent wiring fault, any diagnostic tips?

 

[babaroga]

No diagnostics can help there, simply there is broken wire inside the mirror and has to be cut and extended. It moves when mirrors are closed and opened. I took mine to main dealer and they have fixed it on our GL....later versions post 2008 apparently do not have that problem.

If you can waste a few hours with multimeter, enjoy, or pay hour labour to main dealer.

 

[Bruiser]

Thanks. Brake wear indicator has just come on so at least I can kill 2 birds with one stone!