My door mirror has stopped auto dimming, the interior mirror works fine and no sign of the usual colour change of a failed door mirror glass. Before I start stripping the door to check for broken wires Etc I want to test the mirror glass to eliminate it as being faulty. Can I just apply 12v to it as a test, or would that just destroy it. They are a bit expensive to be playing about with. If they were £20.00 I would just buy one to try it. Every other function of the mirror works fine.
