David Berry

My auto dimming rear view mirror does not dim.
Anyone else experienced this? The mirror center button on bottom turns on an indicator green light.
Pressing the center button again turns indicator light off.
The mirror does not dim either way. So I’m blinded by the light!
what can I do?

jamesinger

Mine melted halfway. I figure I can put a tinted broadway mirror over it, buy the cheaper flip up one, or buy the super expensive OEM one. It is a loose tooth in my car for sure.

David Berry

But I want to know if it can be fixed.
I wonder if Porsche would just replace the entire mirror,
or if there is a fix for it.
Maybe the sensor is bad and could be replaced.
Does anyone know how this works?

groovzilla

Easier solution is don't let anyone drive behind you at night.

David Berry

That is what I try to do. Put space between the cars behind me.
For some reason, they speed up and follow closer
when I try to get away. Sometimes I drive at illegal
speeds to get away!🤫

jamesinger

https://www.radar-mirror.com/

I have no experience with this company yet...

edit: BTW, I have asked 2 indies and a dealer about it and they all just say it is a full replacement job for mine. I think that is unfortunately the way things are for the most part now. Replace rather than repair.

997.2GTS

There are two sensors (photo-diodes) on the mirror body - one on the front facing the windshield that detects ambient light (daylight) and another that is facing the rear window to detect bright lights. The ambient sensor must first register that it is a low light situation before the bright light sensor can operate. If it is a low light situation and there is a bright light shining on the mirror from behind, liquid crystal sandwiched in the mirror is polarized which dims the mirror.

Most likely, one of the sensors (probably the ambient light one) has failed, but photo diodes are tough pieces of hardware for the most part. It's a very cheap circuit that you will pay a small fortune for.

David Berry

Decided to go to Momentum Porsche in Houston.
The advisor didn’t come to the car to greet me.
So I walked into the service area. This guy was
sitting at his desk, looked up at me and said ‘yeah?’
kind of like WTF you want, driving up in an eleven
year old 911S cab? Finally got his attention, he knew
nothing, except to say they typically just replace the whole unit.
I asked if he knew how to remove the mirror
from the windshield,🤷‍♂️
Didn’t know, I asked if the mechanics knew, “yeah, but the guy isn’t here now.”
meaning, go away!

I am very disappointed with Momentum Porsche,
I purchased three 911s from them.

cdk4219

Maybe you should have set up a service, so they could fix it.

Phrog Phlyer

As a double check for the operation - On my 09 C4S cab - While it's in the garage - I can turn the car to "on" (not started) with the mirror "Auto" button in with green light on. Shine a small pencil light at the sensor and the inside mirror along with the 2 outside mirrors go dark. Take the light away they brighten up. Do any of your mirrors darken?

David Berry

Yes! Both side view mirrors dim when I shine light
on rear view mirror, the rear view does nothing.
Something about rear view mirror glass isn’t right?

Phrog Phlyer

There are several DIYs on the Planet9 site. Google "porsche rear view mirror remove planet9" and you will find them.
https://www.planet-9.com/threads/rem...mirror.108149/

David Berry

Thank you for the suggestion!
Have a merry Christmas

Hatzenbach

@David Berry I have exactly the same problem. Were you ever able to figure out the root cause?

David Berry

I have come to the conclusion that the dimming does work, but the dimming is just not dimming to my satisfaction. It does dim just like the side mirrors. It doesn’t dim like other mirrors that have the push tab to adjusts the mirror for night driving,
not as effective. I wish the op had not ordered the self dimming mirrors. Maybe someone can chime in and describe their self dimming rearview mirror.