Electrochromic mirror not working

[Asfalto]

1998 Tahoe LT 4dr
Hi everyone, my mirrors don't fade when hit by a light from the back in the night.
Temperature and compass display reads fine and dims when outside is getting darker; the 2 bottons (temp and comp) work fine too.
The led at the bottom of the mirror is always off.
any trick? Any suggestion?
Thanks

 

[Yukon&Tahoe]

Which mirrors aren't auto dimming..... interior rear view, exterior side rear view or both???

 

[SunlitComet]

check for the reverse lights voltage that may be constantly on from a short some where. it will be the light green wire and should only have 12 volts when in reverse if it works fine then the mirror is defective internally.

 

[Asfalto]

All the mirrors aren't dimming, and, as I said, the led is off.
The owner manual says to press the Temp botton for 6 seconds to turn the auto-dimming on but it doesn't work.
I'll check for the reverse lights voltage.

 

[Asfalto]

solved! I presses the temp botton for 12 seconds (instead of the 6 said by the owner manual) and the auto-dimmind feature went on!

 

[saif najd]

Mine is not working at all!!

I am thinking of doing a new thread regarding this matter

Today I been to the "hill" junk yard and tried 6 mirrors anf nothing dead

 

[SunlitComet]

is electrical power even reaching the mirror?

 

[saif najd]

I think so,

I did a new thread full of info I found regarding this matter please check

http://www.tahoeyukonforum.com/forum/showthread.php?t=49703

Rear view mirror "NOT WORKING"