So when my block heater was installed they gave me a Lounge loaner that had an auto-dimming mirror. Fiat doesn't offer a Homelink mirror, but the auto-dimmer wires up the same way. So it got me thinking: I can get a homelink auto-dimming mirror on Amazon for $160, and they're easy to install if the overhead light fixture has the right wires present. They need three wires: ground, continuous +12, and ignition-switched +12. Will my 500 Sport (no sunroof) have those three up in the light assembly already, or would I have to run a new wire for one of those? The lights should have a good ground, and presumably a continuous +12, although maybe not given their funky controls. But the question is, will there be an ignition-switched +12 up there for anything?