GM Service Manual Online
For 1990-2009 cars only

Information on Heated Electrochromatic Outside Rearview Mirror Performance

Subject:Information on Heated Electrochromatic Outside Rearview Mirror Performance

Models:2009 and Prior GM Passenger Cars and Light Duty Trucks (including Saturn)
2009 and Prior HUMMER H2, H3
2009 and Prior Saab 9-7X



Defrosting Time / Performance Concern

Customers may comment that the electrochromatic (auto-dimming) outside rearview mirror used on the driver's side of many GM vehicles is slower to defrost than the passenger side outside rearview mirror.

This is a normal condition. The glass on the driver's side electrochromatic mirror is twice as thick as the traditional glass on the passenger side mirror. The heating elements for the mirrors on both sides draw the same wattage, therefore the driver's side mirror will take approximately twice as long to defrost as the passenger mirror (Approximately 4 minutes versus 2 minutes). Should a customer indicate that the driver's side heated mirror is not functioning correctly, verify its function based upon this information prior to replacing the mirror.