Power Mirror Gremlins

Post Fri Jan 20, 2006 5:32 am

Hey all,

Both of my wing mirrors seem to be in different stages of failure. Can't quite figure it out: we've pulled both mirrors off the car and they bench test just fine. The switch has also been tested off the car and is fine as well. Get it all back on the car and the passenger side is dead dead dead and the driver's side only adjusts left and right.

I've checked the archives and understand that the big wiring harnesses in the door frames can suffer from pin corrosion, but that doesn't explain the half-functioning driver's side. Don't the wires just run directly from the switch to the mirror? I'm stumped!

Post Fri Jan 20, 2006 9:41 am

Bench tested or not, change the mirror switch, or at least open the switch up and give its insides a good clean. (Easy, but many loose parts).
For the passenger mirror, the door pillar sockets may be the problem.
Problem is usually with the blue/white wire, as this is live all the time the ignition is on, and so most likely to corrode.

Post Sat Jan 21, 2006 3:43 am

Thanks again, Brian.

Turns out the problem was with the wiring itself (much like my speedo failure). This past summer a friend and I both had our E30s repainted and both cars had the doors off. This seemed to disturb the delicate 18-year-old-car electrical balance and caused us both a world of electrical headaches.

My mirror problems were solved by running all-new wiring in the passenger door. My mechanic showed me how the wires had become MUCH stiffer and more brittle over time. It was interesting, the length of wire that was inside the door was still supple, but where it exits the door it had become almost unbendable!