Install auto dim mirror

[Expy2020]

It blows my mind that my 2020 XLT with luxury package, leather, pano roof, etc, had a manual flip rear view mirror. So today while at the scrap yard I happened across a 21 hybrid super base model explorer and it, of course, had an auto dim mirror. And even better, it was secured with a t20 torx screw instead of a spring clamp so it was easily removed. I snipped 18" of the wire harness with the mirror.

It's a GNTX 931 mirror and has 5 wires going to the harness/mirror. I believe this mirror has a backup camera monitor which I won't use (my camera is in the big dash screen). So I'm curious as to which wires are power and ground and can't find a schematic anywhere.

It's a 16 pin harness but only has 5 wires, a light blue, a light blue with orange stripe, a white, a Grey, and a white with red stripe. There is no light in the mirror to indicate power so trial and error will be difficult.

 

[Expy2020]

OK, trial and error revealed it's pin 1 for power and 4 for ground, on this mirror that is light blue for power and Grey for ground. The other three wires were for the camera, should have been a dead giveaway once I peeled back the fabric tape and found the other 3 wires wrapped separately in shielded metal tape.

Now as far as installing, I'm fairly confident I can remove my mirror without breaking the windshield since it's the flat C shape spring clip as opposed to the locking tab on the bottom side of the mirror mount. I broke 2 windshields at the junk yard trying to remove those style from other ford's but they all had mics in the mirror and I wanted the factory smooth mirror with screw mount.

How do I remove the black plastic cover above the mirror where the sensors are located, and then how do I drop the overhead console? I believe I can hook power and ground to those little purple lights that only come on when the headlights are on. Just need to get access...

 

[Dale5403]

This thread should help. How to: - Power mirror circuit: hard-wiring radar detector, camera, etc.

 

[Expy2020]

Got it done. Broke a small chip out of edge of that stupid overhead console. It did not want to budge. I got it all together, tested and verified it darkens using flashlight on my phone, put it all back together and went for test drive. It doesn't really seem to dim at all which is kinda disappointing. I only have the factory tint nut evidently it's too dark for bright headlights to make the mirror darken unless they are right up on you with high beams. The mirror in my F150 and the one in my Focus do a better job and they have factory tint as well. I know it is working because I can shine a light at it from the back seat and it darkens up real quick. Kinda bummed, chipped my overhead console for nothing and might just pop the old flipper mirror back on and tuck my cord back up behind the black plastic cover.

 

[peterk9]

Got it done. Broke a small chip out of edge of that stupid overhead console. It did not want to budge. I got it all together, tested and verified it darkens using flashlight on my phone, put it all back together and went for test drive. It doesn't really seem to dim at all which is kinda disappointing. I only have the factory tint nut evidently it's too dark for bright headlights to make the mirror darken unless they are right up on you with high beams. The mirror in my F150 and the one in my Focus do a better job and they have factory tint as well. I know it is working because I can shine a light at it from the back seat and it darkens up real quick. Kinda bummed, chipped my overhead console for nothing and might just pop the old flipper mirror back on and tuck my cord back up behind the black plastic cover.

The factory tint should not have any effect on the mirror's ability to darken.

Peter

 

[Expy2020]

The factory tint should not have any effect on the mirror's ability to darken.

Peter

But it does. The explorer is long, and the roof slopes downward towards the rear glass. My wife and I are tall and have the mirror up as high as it will go against the front windshield. I tried flipping the mirror upside down so it's light sensor is on the bottom hoping to improve it's ability to get light from the rear window.

I think I'll try covering the forward facing sensor on the mirror and see if that impacts daytime driving. Covering it will trick it into thinking it's night time but it's always soo dark inside the car (with the moon roof cover closed of course) it probably won't make a difference in daytime driving but might help at night. Bright headlights from oncoming traffic (more and more common these days with LED and HID headlights) may cause the mirror to assume it's daylight out and not dim at all. This is fine, but if you've got these bright lights behind you and on coming traffic seem as though they would defeat the system entirely.

 

[peterk9]

But it does. The explorer is long, and the roof slopes downward towards the rear glass. My wife and I are tall and have the mirror up as high as it will go against the front windshield. I tried flipping the mirror upside down so it's light sensor is on the bottom hoping to improve it's ability to get light from the rear window.

I think I'll try covering the forward facing sensor on the mirror and see if that impacts daytime driving. Covering it will trick it into thinking it's night time but it's always soo dark inside the car (with the moon roof cover closed of course) it probably won't make a difference in daytime driving but might help at night. Bright headlights from oncoming traffic (more and more common these days with LED and HID headlights) may cause the mirror to assume it's daylight out and not dim at all. This is fine, but if you've got these bright lights behind you and on coming traffic seem as though they would defeat the system entirely.

I had a 2017 Platinum, a 2020 Aviator and currently a 2023 Aviator and no issues. The Aviator also has a sloped roof. The Explorer is 198.8" and the Aviator is 199.3" in length. If the tint was the issue, I'm sure that there would be a thread and many posts on it, but there aren't.

Peter

 

[Expy2020]

Maybe I'm just expecting it to dim more than it does, I've got two different gentex models in my truck (oem Ford, no display) and focus (auto dim mirror from kia with homelink buttons). It will dim fine at a stop light with a truck behind you, but not so much when moving down the road with distance between vehicles. Guess my expectations are just too high or I've been spoiled with better working mirrors.