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Easy swap but a pain to get the two longer screws back in correctly, glue issue was not a problem but did the swap on a warm day and the plug came loose fairly easily truck was sitting in the sun for a few hours which might have helped

Edited by Raven2m
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I recently received my 2021 Trail Boss Custom and of course it has the “dumb” mirror. I went ahead and pulled down the console which only has OnStar and overhead lights, pretty basic. There are the 3 unused harnesses like others have mentioned. The dab of glue that holds the harness I need to upgrade my mirror is a little bit of a pain. I used a flathead screwdriver and sort of dug into the glue and just slowly wiggled and pried and it came up.


Now I know the harness is there I will order mirror with the garage door controller. Did anyone ever figure out what the other two harnesses are for?




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  • 3 months later...
  • 2 months later...

So I did this swap over the weekend.  I went with part number 13540312.

Got the harness freed pretty easily by using a hair dryer.

I did break the clips on the mirror cover insert so I had to order a new one of those.

I will say I haven't really notice the mirror working.  I've read others say it's not as noticeable as others, but I also haven't driven at night yet.  The closest I had was this morning when the sun was coming up.

I also have my windows tinted.


Anybody else have something similar?  Wondering if the mirror I got isn't good?

Thanks for the feedback.

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I have the Gentex auto dimming mirror for sale. Had it in my 2021 Silverado. Works great, excellent condition. Plug and play, no wiring needed.







Edited by steig
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On 10/22/2021 at 2:41 PM, Hotwheel said:

Is there anyone that went to install the factory auto dim mirror and couldn't find the plug. I have a 2020 WT and I don't think it is there

Mine was super easy to find and connect to mirror.

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  • 2 weeks later...
On 11/4/2021 at 11:40 AM, Hotwheel said:

Well WT models do not have harness with the plug for the auto dim mirror. Can anyone tell me the color code for the wires?

Black -

Red +

Green ?

Pink ?

Gray ?


Green is reverse trigger wire

Pink is auto dim outside mirror(unsure if left or right)

Gray is the other auto dim outside mirror(also unsure if left or right)


You really only need positive and ground. The reverse trigger just disables the dimming when you're backing up. It's only really an issue if you back out of a dark garage into bright sun, but I've had it on other vehicles with the auto dim on full time and it never bothered me.

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