A couple days ago I tore through the manual... sure enough it is more and just a switch... The $132+ is for an entire heater/AC panel. The heated mirrors portion has 3 wires going in, Ground, fused 12v, and 12v going out to mirror. Pushing the button actually dumps a ground from the control circuit to a relay which sends the 12v to the mirrors. Yes, after 15min the ground drops and the relay opens. If you press the button again without turning the key off, it only heats for 5min at a shot before dropping the load again. I'm currently shopping for a cheaper alternative, switch, relay and timer but may end up with the factory panel if I find an honest dealer or luck out in the junk-yard this weekend. I've been quoted $132, $168 and $195 and $210 for the same part. From 3 dealers, yes 3 I lost the sheet I had the part # on so went back the next day, same parts guy raised the price from $195 to $210... Stealers gotta love'm
-Matt