the rearview mirror in my new 6 speed with Onstar always sets itself to dimming automatically, day or night. My other 6 speed with the regular mirror never dimmed automatically, day or night.
Are the setups different on the 2 mirrors. Yes I read the manual, it doesn't say there is a difference.
I thought it dimmed only when you push the button, and then the green light comes on. My first 6 speed without Navi worked this way, I would push the buttom to turn on the dimming. On the new Onstar mirror is seems to always turn on the dimmer by itself, it's annoying. Anyone know why the differences in the 2 mirrors??
Why would one turn itself on all the time and the other one never did this?

 

I just got a navi to replace my non-navi too. I think the mirror is right out of the trash....i mean the parts bin of GM since they provided Honda with the Onstat stuff. I noticed its a different color too, the Honda one is more blueish and the GM? one is more greeny/yellow. I haven't noticed the dimmer switching on and off though.

 

i noticed the other night when i had a loaner CL that the no navi CL dims much better and the navi version(mine) doesn't dim that well

 

You're right the non-Navi mirror seemed better view and color.
The Navi mirror also vibrates more, guess cause it's heavier.
Neither mirror is wide enough. I guess I'll just leave dimming on all the time. Guess I don't know how it's supposed to work.
Maybe you leave it on all the time and it dims when needed?

 

My OnStar mirror doesn't vibrate at all. It's really quite rock solid. Since I'm the only driver of my car I can honestly say that I have not had to adjust it since I first got the car.

Maybe you need to have the mirror adjusted/tightened.

I also leave the dimming on all the time and **knock on wood** so far no issues. I know people have posted that the dimming material fades over time, but the replacement is considered a warranty fix.

The mirror knows to dim by comparing light sensors in the front and back of the mirror. When the back sensor has more light to it then the front (like someone's headlights, or the sun) then the mirror dims. The mirror doesn't dim when lighting is near equal front and back. I see no issue with leaving it on all the time -- it's an 'automatic' mirror and I intend to use it as such. Pressing the power button on and off sort of defeats it being automatic, at least how I see it.

 

I believe the button is to enable the "auto dimming" if you turn it off it should stay daytime mode all the time.

 

Correct

 

Here's the difference. On my non-Navi mirror the green light (or dimming mode) NEVER came on UNLESS I PUSHED THE BUTTON.
On the Navi mirror, the green light goes on by itself, thus the dimming turns on automaticaly as the default when I start the car. The non-Navi mirror did not do this ever.
i just couldn't understand why they would operate differently.
The navi mirror also vibrates slightly if I'm idling, say, with the brake on and in gear, the non-navi mirror did not do this ever.

 

dont notice it much with 15% tint on rear window.