OK, this is for those of you who have access to a service manual or have been to Crossfire training. Does anyone know the theory of operation of the auto-dimming rear view mirror? I'm trying to make some sense of why it does what it does when it does.

I know that it has sensors (I'm assuming photocells) facing forward and aft but for the life of me I can't nail down which conditions will make it dim or not dim. I eventually want to find a way that I can manually dim it if I want to.

Interesting side note: Did you ever notice that because the electrolyte in the mirror has kind of a blue-ish tint it makes it look like everyone behind you has HID headlights?

 

the mirror should dim if the front sensor senses darkness and the rear sensor picks up light. this would be comparable to driving at night with a car's headlights behind you. to manually dim it, hold your finger against the front sensor. if there's enough light for the rearward-facing sensor, the mirror will start to dim.

its not an instant transition; it may take 30 seconds or so to convert.

 

Do you happen to know if the mirror is self-contained or driven externally?

 

its got to get 12V from somewhere. I would bet there's 12V and ground going to the mirror --

 

Switched output and ground. Because it stops to darken when the interior light is on or the backup lamp.

 

Everyone, I got a chance to poke my nose in a Crossfire repair manual over the weekend and I thought I'd follow up with you on the way the mirror works. According to the technical description, the mirror is a non-repairable, self-contained unit. It gets +12v from a supply line in the head liner. It also has a sense line that monitors the reverse lamp circuit so that when the car is in reverse the mirror will not dim. This means that those of you with the standard mirror could probably install the auto-dimming one without a whole lot of fuss.

On a somewhat related note, I also saw that the side mirror heaters run continuously when the ignition is in the on/run position. These mirrors are also non-repairable so if a heater fails the entire mirror must be replaced.

P.S. This was a manual for 2004 models.

 

i thout the mirrors heaters ran only when the defroster was on. interesting; thanks --

 

You're right about that. I did the acid test, I felt them with the ignition on for awhile, then when they were obviously not heating up, I pushed the defrost button. Well, I think you now what happened hehe