FAQ: Side Mirror Problems (heated, auto-dimming, tilt)

moldymac wrote:

The mirror on my 97 was cooked, no heat, just dimmable.

Ah, I'd only seen the combo units cooked before... My own '97 dim-only is crystal clear.

I think this is going to be one of those times that we'll have to agree to disagree.
I'm still going to bet that the failure rate is much higher on the heated ones, because summer heat is slow & gradual, and heating a sub-freezing unit up to 140+ degrees in the space of a few minutes just has to take a bigger toll - even if the actual failure point is reached in the summer. Now if someone has an infrared thermometer gun, it would be interesting to know hot the mirrors actually get in a cool garage... I just know that the thermistor on my Cadillac mirror was something like 145 degrees.

BTW, has anyone had the inside mirror cook? As we all know, a car parked in the sun with the windows closed can get up to furnace temps, higher I would think than the well-ventilated outside mirror... Even if the sun were shining directly on the face of the side-view mirror, it should reflect most of the heat - it's a mirror.

All good points. And , no Ive never put my infrared thermometer to any of the mirrors.
Remind me come this winter and I'll see just what temp they get up to when ambient is very cold. That's if we can remember to remember.
And I have never had the rear view go bad- another good point.

145ºF? Ouch!!! There's no way the glass heats up to 145ºF. It only needs to go above freezing to melt the ice. Mine takes several minutes to start melting in freezing temps.

Temp testing soon...

Rickw wrote:

All good points...
And I have never had the rear view go bad- another good point.

Thanks for acknowledging my 'logic'...

AA wrote:

It only needs to go above freezing to melt the ice. Mine takes several minutes to start melting in freezing temps.

Temp testing soon...

Thanks for testing. Did you replace your driver's side mirror with OEM, or add another mirror on top? If the latter, please check the passenger mirror temp.


Oh hey! I just thought of another reason that the later cars would suffer more damage: Despite what my owner's manual says (like the garage opener being capable of rolling codes... ) up through '97 the rear defogger still only ran for 9 minutes, period. The next year they allegedly added speed to the equation, so that the timer doesn't apply above 30MPH... Thus, the mirror heaters can run indefinitely on those cars.


(( Now where the hell is my Ritalin? ))

On the '98 it will stay on indefinitely if driving above 25 mph I think.

I have not replaced mine yet. Almost all the fluid has leaked out, so I can see with it pretty well. I will test the actual mirror temp with a cooking thermometer accurate to 0.1ºF. I've used it on brake rotors with success.

You mean like an electronic fork?

Yes, something like that, digital, very accurate.

my 95's mirrors are kind of yellow and they do cut glare at night... I dont know if they're auto-dimming but I like them

jeffyd123 wrote:

my 95's mirrors are kind of yellow and they do cut glare at night... I dont know if they're auto-dimming but I like them

If the owner's manual is to be believed, only the rear-view mirror had an automatic dimming option in '95.

ahh ok. thanks... maybe its an anti-glare coating.

Don't believe everything the owners manual tells you. It also tells you that the supercharger cannot be serviced and that you don't have to change the oil in it. On my 95 the drivers side mirror and rearview definitely dim. The passenger side does not seem to, not sure if its broken as none of them move or if GM in their infinite wisdom decided only the light shining in your eyes from the driver side can blind you.

Oh, I know, Derek. The manuals have to be written, illustrated & printed by the time the cars roll off the assembly line, and they always seem to have a few photos from the previous year, and promises from the next... that's why I said, "If the manual can be believed."
For example, I bought a rolling-code garage-door-opener receiver off of eBay, because my '97 manual HAS the instructions for rolling-code programming. After an afternoon of abortive attempts to get it to work, a call to HomeLink told me that my car was built before they were even selling GM that unit... So I had to re-sell it and buy a dip-switch-code receiver.

However, as neither the '95 nor '96 owner's manuals mention the outside dimming or the compass, I figured it was a safe bet that the 2-mirror-dimming wasn't introduced until the compass-mirror with the slide-switch (and you're right, the passenger mirror doesn't dim, probably because the glare is much less from the convex surface...)
.

Derek wrote:

Don't believe everything the owners manual tells you. It also tells you that the supercharger cannot be serviced and that you don't have to change the oil in it. On my 95 the drivers side mirror and rearview definitely dim. The passenger side does not seem to, not sure if its broken as none of them move or if GM in their infinite wisdom decided only the light shining in your eyes from the driver side can blind you.

it's the latter...

Albertj

... And we all know how 'wise' GM can be. Its possible, judging from what I've read on here of people having options that supposedly weren't available for that year, that GM did A LOT of mid-year re-designing of these cars. Great! That makes it even more difficult to get the right part.

It could be worse, you could have a '94 Riviera...

I want one of hose 94's in Purple.

If you can find one let me know.

Thanks, Bubba

Rickw wrote:

I want one of hose 94's in Purple.

If you can find one let me know.

Thanks, Bubba

Make that a purple V8 convertible!!

Eldo wrote:

Rickw wrote:

I want one of hose 94's in Purple.

If you can find one let me know.

Thanks, Bubba

Make that a purple V8 convertible!!

Now we're on the same page.!!!!!!

I did a test yesterday on my trek home from work, about a 35 minute drive at 65-70 mph. The temp showed 71ºF when I left, 72ºF when I arrived home. Here's the climate control upon leaving:



I rigged the thermometer with some tape; am quite sure I got some looks on the road, lol. The mirror was hot at first (85ºF), but once we got moving it cooled to ambient, 70.7ºF. This is when I activated the heater:



The mirror heats up slowly, about one degree every 30 secs at first, then slower and slower the higher it went. While cruising 65-70 mph, it took more than 15 mins to reach the peak temp of 81.1ºF:



So we know that at cruising speed, the mirror heater will elevate the mirror face about ~10ºF above ambient. The next thing I wanted to know was how it performed at speeds from 0-25 mph, the range where the heater is timed to around 10-15 mins. I slowed down and drove around my neighborhood, and the temp did rise some more - to a peak of 85.4ºF (ambient was now 72ºF):



Finally, I stopped the car and sat idle for a couple minutes until the heater turned itself off. Interestingly, the mirror temp continued to rise for a while after, likely the result of heat being radiated through the wheel wells and from under the car (I have a strong feeling my headers produce more heat compared to manifolds). I could easily feel it with my hand near the sill. Peak reading was 95.0ºF:



Lessens learned:

• At highway cruising speed, the mirror heater increased glass surface temp to ~10ºF above ambient.

• At speeds below 25ºF, the mirror heater increased glass surface temp to ~13ºF above ambient.

• Sitting idle, the mirror glass surface temp increased ~23ºF above ambient, regardless of whether or not the mirror heat was on or off.

Any solutions for these heated mirrors?

Well, unless the limited contact of this probe-type thermometer is causing a low reading, it looks like they did figure out that they had to go with cooler heaters when they added the dimming feature... My Cad mirror definitely got a lot warmer to the touch than this one is doing. Thanks Aaron.

Derek wrote:

... And we all know how 'wise' GM can be. Its possible, judging from what I've read on here of people having options that supposedly weren't available for that year, that GM did A LOT of mid-year re-designing of these cars. Great! That makes it even more difficult to get the right part.

sometimes that happens due to collision repairs. You'd be *amazed* at how well a modern collision center can repair a car. They can if they want do work that is not easily detectible at all. I think Morad recently dismantled a '95 that had a '98 interior - probably a recovery & repair of some sort.

As for the mirror, I wonder what the mirror heats to in teh winter when it is say minus 15F out?

Albertj

I'd bet just warm enough to melt the ice covering it. The ice could act as a blanket to keep in the heat, then once it melts the mirror's surface temp would drop back below freezing. That's my best guess. With no ice or snow insulating the mirror, I think it would still only raise glass ~10-13ºF above ambient.

groschen1936 wrote:

Any solutions for these heated mirrors?

this thread is loaded with discussion, but not many solutions. Basically your option is to buy the plate-glass replacement and glue it over the old mirror. Heat still works a little through the glue, but no dimming.

Or spend $400 with the company who bought out GM's stock. last time I checked with them they had 25 or so left.

Eldo wrote:

Well, unless the limited contact of this probe-type thermometer is causing a low reading, it looks like they did figure out that they had to go with cooler heaters when they added the dimming feature... My Cad mirror definitely got a lot warmer to the touch than this one is doing. Thanks Aaron.

I thought I read that the heated mirrors and rear window defroster would not activate unless the ambient air temp was 48* or less.
I could be thinking of a different car or system all together. I can't find it yet in the FSM.