Jeburnett

Audi apparently has programmed the heated mirrors to not turn on if the outside temperature is above 59F. In Florida where it rarely gets that cold but has plenty of humidity to fog up the mirrors.

Is it possible to alter that trigger temperature setting, somewhere, somehow?

Thanks,
Jonathan

arU4ic

I'm curious how you know that? And yes, that temp seems pretty high.

Jeburnett

I read about the 59 degree setting from some Goggle searches I had done a few months back. It wasn't until we had some real temperature drops that I had the opportunity to see the heaters turn on. It was in the 50's somewhat below 59 so it seemed consistent with the reference I had read.

I've spoken with the service guys at the dealership and they didn't even know about the limit and couldn't answer if it was override-able.

hayde_bre

I never really had fogging issues with my mirrors, I generally use it to keep water off during misty/rainy days, so my suggestion may not be the best, but did you try coating it with anti-fog or some sort of repellent since you don't really need the heat?

Jeburnett

Happens here when I leave it parked outside and the dew that forms on the car, also forms on the mirrors. Even if you wipe them dry, they stay filmed until they warm up.

Your suggestion might help and if I didn't have heated mirrors, I might try that to see if it helps. I've driven a Lexus RX for 12 years with heated mirrors and so I've been able to burn off this moisture effortlessly in that SUV and one of the features I desired on the Q7 was this same ability. It will work but apparently only when the weather in Florida approaches what the designers in Germany expected for their climate.

Overriding that setting or completely bypassing the temperature check would make that feature work for me down here.

JT4

Below is a thread I started approx a 1-1/2 years ago in regards to the heated mirrors.. It drives me crazy that I can't turn on the heated mirrors in the warmer weather when it's raining to keep them clear. Previous vehicles I've owned, and current vehicles (non Audi) I own allow me to put the heated mirrors on in the middle of the summer if I so choose...

https://www.audiworld.com/forums/q7-...rrors-2930522/

Corgiman

dohturdima

Classic example of over-engineering.

ConservativeConsumer

I believe the VAG settings for temperature threshold is not 59F, but 69F. This fact was clearly stated in my now bought-back VW Touareg's Manual. I recall that a few Club Touareg folks were trying to reprogram the temp settings for heated mirrors with no success. I would guess that this restriction is related to a self-dimming function of the mirrors. The self-dimming involves multilayered structure of the mirror with one of the layers being electrolyte inside of sandwiched structure of such mirror.

Jeburnett

I just did an experiment. The outside temperature had fallen to 68-69 degrees, so I got in the car and using one of those infrared "laser" thermometers, I read the mirror temperature to be 68 degrees. When I switched the **** to mirror-heat, the instrument dash reported the mirror heat came on and using the thermometer, I could read an immediate temperature rise. After a few minutes, it seemed to stabilize around 79 degrees, or 10 degrees above ambient. The heat stayed on and so did the display UNTIL I rotated the **** to turn off the heat, which naturally turned it off. When I turned heat back on, the mirror did NOT heat up and the instrument display confirmed as such. I waited for the mirror temperature to fall back below 69 and when it did, the mirror heat did not come back on. I turned off the Q7 and restarted and this time when I turned the mirror heat on, it came on. Briefly turning it off and back on caused both actions to occur.

So, this pretty much confirms 69 degrees as the trigger temperature AND it confirms that the thermistor the car is using for that purpose is in the mirror itself, rather than the vehicle thermistor.

Not sure what it says about the vehicle cycling experience but that may have just coincided with some timeout period (i.e. max number of minutes the heat is on).

Interesting observations...