My wife and I owned a 2003 Trailblazer and the rear view mirror incorporated temperature and compass. Our newer 2009 does not. Can I just buy a replacement mirror that has these incorporated in it or does it not show them because the vehicle doesn't have the sensors?
Please help

 

It's a roll of the dice. It all depends on if the extra wiring is present for the temperature and compass displays, if the wiring is there for the external temperature sensor, and (here is the big one), if the BCM is programmed to accept the sensor inputs and then send them to the display.