Your passenger side-mirror motor may not be dying

Hi Pals, I just got my 2003 996 C4S back from the shop (preventative work) and my side mirror was acting strangely. The mirror was already pointed at the curb, presumably because it was backed into a parking spot at the dealership. I shifted into first and the mirror didn't "return". I thought this was just a glitch and shifted into reverse in an attempt to "reset" the mirror and wake it back up by shifting back into first. When doing this, the mirror - again - didn't return. In fact, I put it into reverse again and the mirror did something that made me nervous: it tried to "lower" the mirror to the curb but got stuck in a loop. The computer was clearly trying to get it into a specific state, but it couldn't, so the motor kept trying to "lower" the mirror angle without stopping. You may not even realize this is happening if you are parked for a while and you don't see the mirror "shivering" from trying to lower. If you have music on in your vehicle or if you're talking, you won't even hear the motor. At this point, the mirror started to display behavior that was similar to what other people have reported online (including this forum) as motor failure. I used the joystick to point the mirror back to the appropriate level. But, it would lower but not "return". Either the mirror wouldn't return at all, or the mirror would attempt to raise up and would stop way early, or wouldn't raise up to the full position. This was consistent. I realized this was a programmatic issue because somehow the computer that controls the motor was trying to ascertain some semblance of azimuth that was now out of sync with the computer. To clear this issue, on my 996 I did what the instruction manual told me to do to clear the seat memory. In my case, I pressed the "Key" and "2" buttons on the powered seat controls, simultaneously, for 3+ seconds, to clear seat memory. I did this with the passenger side-mirror at the appropriate driving height. I then kept the shifter in neutral, slightly adjusted the seat a bit, and made sure the mirror was slightly different than my prior position, and saved the current seat state in the Key button. By slightly changing the seat position and the mirror position, this ensures that the computer stores a variation of the values in memory. By keeping the shifter in neutral, it also ensures the automatic mirror-lowering function is disabled. Next, I shut off the vehicle, took the key out, opened and shut the door, and locked the door to shut off the OBC. I then unlocked the car and turned the power back on. To ensure the new settings were being recalled, I pushed the Key button. This ensures the new settings are not only set, but are being used by the computer. I then shifted into reverse. Now the mirror automatically lowered. I saved the Key memory. Now, when I shifted out of neutral the mirror automatically returned, fully, to its driving position. I then verified that the new configuration, including full side-mirror lowering/returning, was functional by going through the full cycle twice. So, for anyone that is seeing abnormal side-mirror behavior, don't immediately plan on replacing the motor. It may, in fact, be that someone accidentally bumped your mirror to a position that desynchronizes the mirror's position from the OBC's memory setting. Since the computer can no longer "detect" the position of the mirror, it gets confused and just stops trying to adjust the mirror. Resetting the computer's memory will help with this, presuming the issue is *not* motor related. If you go through these steps and the "return" function still doesn't work, other issues may be possible (motor failure, lubrication, etc). But, since I didn't see this process anywhere and most people presumed the issue was a motor change, I thought I'd share this solution as it will save you ~$150 and your time. Best, ninemouse

Quotes source post: 18079138

Ah just to clarify I hit the "Key" and "2" buttons on the memory panel to clear the state, not "Key" and "M" (which stores your current settings).

Nice post! i just reinstalled my seats in my 2003 Carerra,and i notice that the driver side mirror is not dropping down when going in reverse,and when adjusting the mirror from the drivers side control it will only move in or out and not up and down? any suggestions? maybe i need to do the procedure you describe(reset)......thanks Randy

I didn't even know the mirror dipped! Guess I'd better dig out the owner's manual...