1999 GMC Sierra whats this for?

1999 GMC SIERRA
93,000 MILES • V8 • 4WD • AUTOMATIC
Avatar
ORION101
  • MEMBER
  • 4 POSTS
On the rear view mirror there are two buttons one labeled comp for compass ,which turns on the in mirror compass.The other labeled mirror, which turns on a green light.What does this mirror button do besides turn on a green light?
Aug 28, 2010 at 12:05 PM
Advertisement
Avatar
BLUELIGHTNIN6
  • CERTIFIED EXPERT
  • 16,542 POSTS
Hello and thanks for donating


I'm sure you have seen the little flap that you flip when bright lights are in your mirror and it will darken the mirror , right? Well, that's what this button is for. It's an automatic dimmer. If you turn it on (green light on) than when it detects bright lights in the mirror it will automatically darkent the mirror so the bright lights are no longer so bright ;)
Aug 28, 2010 at 12:19 PM