2001 Auto Dimming driver door mirror

[Beachbums]

The auto dimming driver's mirror is stuck in night mode. It is dark green all of the time even during the day. The interior rearview and passenger mirror, all function normally and turn dark when there is a car behind me
at night. I believe all three mirrors run off the same sensor in the rearview, so one would think it is not the problem.
Is there an easy way to correct this problem?. Disconnect the battery overnight to reset the computer? Would this damage anything else?
Or is this a trip to the dealer to have my wallet extracted through my nose? Thanks.

[stuzman]

Originally Posted by Beachbums

The auto dimming driver's mirror is stuck in night mode. It is dark green all of the time even during the day. The interior rearview and passenger mirror, all function normally and turn dark when there is a car behind me
at night. I believe all three mirrors run off the same sensor in the rearview, so one would think it is not the problem.
Is there an easy way to correct this problem?. Disconnect the battery overnight to reset the computer? Would this damage anything else?
Or is this a trip to the dealer to have my wallet extracted through my nose? Thanks.

I don't have this option on my 2000 LeSabre, but maybe a description of how the system works can point you in the right direction. Most of this is quoted from the factory service manual for a 2000, but I would suspect that it's the same for a 2001.

The electrochromic (EC) film darkens when a low voltage is applied and this function is controlled by the rear view mirror as you've said. The rear view mirror contains photocells that detect the ambient light level and compares it to the light entering the vehicle from the rear. When the light level from the rear exceeds the ambient level, the EC system darkens the interior mirror and sends a low voltage to the driver side outside rear mirror. The EC circuit passes through the DDM (Driver Door Module), but the DDM does not affect this circuit. So, I would think that you have the voltage missing from your mirror. You could take off the door panel and see if you get some voltage levels at the mirror. Maybe a bad connector, broken wire or possiblility a bad mirror. Here's a website for more info on how it works.

http://home.howstuffworks.com/smart-window4.htm

Hope this helps!

[Beachbums]

Originally Posted by stuzman

I don't have this option on my 2000 LeSabre, but maybe a description of how the system works can point you in the right direction. Most of this is quoted from the factory service manual for a 2000, but I would suspect that it's the same for a 2001.

The electrochromic (EC) film darkens when a low voltage is applied and this function is controlled by the rear view mirror as you've said. The rear view mirror contains photocells that detect the ambient light level and compares it to the light entering the vehicle from the rear. When the light level from the rear exceeds the ambient level, the EC system darkens the interior mirror and sends a low voltage to the driver side outside rear mirror. The EC circuit passes through the DDM (Driver Door Module), but the DDM does not affect this circuit. So, I would think that you have the voltage missing from your mirror. You could take off the door panel and see if you get some voltage levels at the mirror. Maybe a bad connector, broken wire or possiblility a bad mirror. Here's a website for more info on how it works.

http://home.howstuffworks.com/smart-window4.htm

Hope this helps!

Thank you for your reply, stuzman. If a small voltage darkens the mirror, then it is getting the voltage all the time, because it is dark all the time. I think I will disconnect the battery, and if it is still dark, then maybe I can conclude the mirror itself is the problem. Maybe I will take the door panel off an take a look there also.
Again, thanks for the reply and the link.

[stuzman]

Originally Posted by Beachbums

Thank you for your reply, stuzman. If a small voltage darkens the mirror, then it is getting the voltage all the time, because it is dark all the time. I think I will disconnect the battery, and if it is still dark, then maybe I can conclude the mirror itself is the problem. Maybe I will take the door panel off an take a look there also.
Again, thanks for the reply and the link.

No problem Beach, just let us know how it goes and good luck!

[imidazol97]

[quote=Beachbums]. I think I will disconnect the battery, and if it is still dark, then maybe I can conclude the mirror itself is the problem. QUOTE]
\

DO you know which fuse it is? That would be easier than disconnecting everything...

[stuzman]

[quote=imidazol97]

Originally Posted by Beachbums

. I think I will disconnect the battery, and if it is still dark, then maybe I can conclude the mirror itself is the problem. QUOTE]

DO you know which fuse it is? That would be easier than disconnecting everything...

Sounds like a good way to conclude if the mirror is bad.

I can't say for sure at the moment, but my guess would be under the backseat where the battery is located.

[Beachbums]

Originally Posted by stuzman

Sounds like a good way to conclude if the mirror is bad.

I can't say for sure at the moment, but my guess would be under the backseat where the battery is located.

Thanks for the fuse suggestion, but none of them specifically are labled
for the mirrors. Really did not feel like pulling them out one by one. So, when in doubt, read the owners manual. On the rearview mirror, next to the OnStar buttons, is a button that turns off the auto dimming feature.
I tried it in the driveway with my wife's car behind me, and sure enough,
the review and passenger mirrors did not dim when I turned the system off. With the system on the rear view and passenger dimmed. The problem driver door mirror, stayed dim throughout the exercise.
So, I conclude the mirror itself is the problem, and will trundle off to the dealer to see what a replacement will cost. Knowing GM, I will not be able to purchase just the mirror, but will have to buy the whole unit.
Geez, I might have to buy a new door with the mirror on it.
Anyway, thanks to you guys for your assistance.