automatic rear view mirror occluded and malfunctioning

I agree the automatic dimming function is subpar. I recently had window tinting applied to my car and a byproduct of the tinting application was dramatically reduced glare from following vehicle headlights.

 

"It's a feature, not a bug."

 

I've had the auto-dimming mirror in both of my Gen 2 Prius, and never have had the problem you are experiencing. I find that most cars' lights are blocked by the design of the hatch, and higher vehicles like trucks cause the mirror to function as designed if they get to close or have high beams on.
If you wind up using the standard mirror, try to hang on to the auto-dimming one. You may be able to sell it on ebay. I plan to add one when my PIP comes in next year.

 

I have the same issue with my rear view mirror on my IV. I dimmed my dash lights and it seemed to have solved the problem. With the dimmer dash lights, the auto dimmer seems to work.

 

Because you are fortunate enough not to have the same height as OP?
I am fairly tall and the divider doesn't give any problems for me.

 

I don't have a Gen 3, but can the mirror be moved up or down? It might help. I'm not talking about tilting it.

I discovered this one of my previous cars w/auto-dimming mirror, only because someone else posted about it. Usually the best way was to grab the mirror w/both hands to move it up/down.

 

The OP didn't indicate that his height was the problem, nor did he say how tall he is. I'm just over 6' and this just hasn't been a problem for me. Maybe where he lives people use highbeams more?

 

I just double stick taped a piece of exposed film negative (I know how many people actually have that sitting around) cut to the size of the sensor to the sensor. This changed the ratio from front light sensed to rear light with the end result being, AUTOMATIC MIRROR works just like the one in my Prius2.

 

It moves up and down on mine, though it's not easy - I had to adjust it otherwise it gives me a huge blind spot, especially for pedestrians.

 

The auto dimming mirror works as always for me. When it dims, the reflection turns green. I know it works because when a car is far away, their headlights are white. When they get close, the lights turn green. I thought my rear window has green tint. When I turn off the auto dimmer, the lights got brighter and back to the original color.

 

I had the same issue wth the mirror until I dimmed the dash lights. I had the lights turned up to max all the time. By having them dim at night, the rear view mirror dims the headlights on my rear. :mod:

 

My UK based Gen III mirror does allow some limited movement up and down on a link arm. I have it jammed up as high as it can go and it works well there.

 

Front sensor on drivers side, it is about the size of a thumbnail

 

I do a lot of highway driving in the dark hours in my 2010 model 5 and have been very dissappointed with the performance of the Homelink mirror when headlights appear in the mirror. I realize that the spoiler is the most likely culprit of the poor performance but it has gotten to the point that I'm considering replacing the Homelink mirror with a standard OEM mirror. Does anyone know if there will be any mounting issues going from the Homelink to the standard mirror?