W203 - both mirrors only move down !

[Joe Edwards]

Hi all. Interesting thing on the drive home. Went to adjust the drivers (right hand) mirror - and found it would move down regardless of up or down command ! Left and right is ok. Tried the passengers (left) side and it's the same ! So I have a common fault with both sides, which indicates something adrift with a shared thing rather than an individual mirror.

Mirrors fold ok.

So, anyone got a circuit diagramme to save me mapping one out ? Or ideas as to what it might be.

It's a UK spec W203 2006 C220 avantgarde.

Any help welcome - cheers

 

[Alfie]

These cars are prone to the loom fracturing.

 

[EmilysDad]

my guess would be the actual switch ....

 

[Joe Edwards]

OK, I've found some info that the switch unit feeds the front SAM module - so I think I'll start by takin gout the switch unit and having a look to see if I can find if it is switching properly - ie I get an "up" demand whan the "up" part of the switch is pressed. Wierd that it just keeps driving the mirrow down. Thanks for the replies. Any more welcome!

 

[Joe Edwards]

After consulting various resources found on the web, given the light switch S1 is the first common thing, and there was one on ebay for less than £20, I'll await its delivery before I think too hard about this. At the moment I can't see how there is another common thing that could cause such behaviour - the Front SAM passes the CAN commands the door modules - and seems to act as a power distribution and CAN bus B hub for the various mirror functions. Part is due Monday..

 

[Joe Edwards]

Changed it this morning for the one from eBay which arrived nice an early. Sorted, so it was S1 - The light / mirror switch module. Very useful though as I found all sorts of useful stuff on the web and know a lot more about how the car is electrically hooked up -so a good excersise and much better that just watching netflix of an evening ! Thnx.