W211 Mirror - No in / out

[JTcamper]

Hello all,
I have a problem with my W211 E280CDI 2009. The passenger / nearside mirror glass will not go in or out when I press the button on the switch. I have removed the mirror motor / actuator and tested it with a battery and it seams OK. I have also just replaced the switch with a second hand one from Ebay. I didn't fancy paying the dealer £100 for a switch. Anyway it's still not working.
Could the door control module be faulty? I would have thought if the module was broken the mirror wouldn't move at all.
The full mirror retracts too, it's just the glass mirror system I have a problem with.
Any suggestions are appreciated before I start replacing modules etc.

 

[whitenemesis]

Broken wire in the pivot area, very common. Usually it's the fold function that gives it away but maybe the control wire to the glass motor has broken?

 

[JTcamper]

Thanks for the reply. I will go and have a look. It's not warm today....

 

[JTcamper]

Broken wire in the pivot area, very common. Usually it's the fold function that gives it away but maybe the control wire to the glass motor has broken?

whitenemesis - Absolutely spot on! I took the mirror off, stripped it back and check all the cables and one of the small wires had broken near a hard bit of cable sleeve near the pivot point of the mirror. Not an obvious fault at first. The two small wires to the indicator lamp on the mirror were on their way out too. I soldered everything back together and put some heat-shrink tubing over the repairs wires, and also wrapped a bit of self amalgamating tape around the repair. The mirror is now working again.
It really is amazing how much engineering goes into something to do so simple, no wonder cars are so expensive. I just need to put the door card back on tomorrow and all is good.

Thanks again for helping me out.

 

[whitenemesis]

If MB originally used some ultraflexible cable, this would never be a problem..