Mirror Control Unit Replacement (2 Viewers)

[lunchbox 2]

Symptom: Side view mirrors will retract but will not adjust. No motor noise when attempting to adjust mirrors.

There's a post on here suggesting that fixing this problem requires replacing the mirror control unit in the drivers side door. I have a replacement unit I sourced from eBay, but when I installed it (5-10 seconds after plugging in the replacement) I got a long loud tone from the car. The mirrors still don't adjust. Hopefully this thread can solve the problem and we can help someone else who is trying to fix this issue.

Anyone have any ideas what the tone was? I didn't follow any procedure...just removed the door then unplugged the old unit and installed the new unit.

 

[lunchbox 2]

Update - you have to pair the mirror ECU with the car using techstream if you have the control panel on the drivers door for driver seat position memory. My mirror ECU is not getting power at the moment, will update this when I keep troubleshooting in the hope it may help someone else down the line.

 

[lunchbox 2]

For those of you with the same problem on a 2003, here is some helpful info: your mirror ECU receives 12v switched through the ACC 7.5A fuse on the drivers side footwell, and 12V constant through the ECU-B2 fuse in the box in the passenger footwell. If you take off the door card you can unclip the connector for the mirror ECU and test to see if it is getting those voltages. In my case I found the 12v constant wire is broken somewhere in the wiring harness between the drivers side footwell and the mirror ECU connector.