I started up my 1987 IROC last night and noticed very light wispy smoke coming from my auto dimming mirror - a cool option in 1987. Are these things known to go up in my smoke? I found another on eBay with burned wires? I'm a litle concerned at this point about replacing it and I haven't looked into it yet to see if that circuit is powered with constant 12V or not. If so, that could have been disastrous

 

It should be switched, otherwise, it would be on constantly, and drain the battery.

 

I'm not familiar with the old (more like ancient) auto-dimming mirrors that our cars had optioned but the newer auto-dimming mirrors are wired differently for different vehicles. Some functions are always hot and some or all functions may be switched power. The newer ones draw such a small amount of power it doesn't make a difference. When I tested mine it drew less than one amp with the auto-dimming function in use, the compass lights on and the temp and compass on. With mine being seldom driven though it made more sense to wire it to a switched power, especially being that mine has the homelink buttons.

One time when I was testing a mirror from a wrecking yard I connected the power wire to the wrong circuit and I fried something and got the little wisp of smoke you described. You may have some wiring issues. Remove the connector and test for + and - voltage at the correct terminals and check your fuses.

Those mirrors are rare and I've never seen one in real life, I would recommend that if yours is ruined to replace it with a newer style auto-dimming mirror and find an original. When you find an original I would not install it, instead just keep it in a safe place as they will be worth big money in the coming years with the now occurring explosion in original thirdgens.

 

thanks for the good advice... I'm curious to open mine up and find out what went wrong with it

 

Probably the small motor that pivots the mirror day/night.Mine did that the same thing years ago.Started smoking while on the fwy, i unplugged it, later opened it up & the little motor was fried.I swapped the motor from a broken one i had & it worked fine afterwards, but the later style are much nicer, i kept the original one though.

 

I have a bunch of these dimming mirrors.Some work and others don't.These we're also used in Cadillac,olds toronado and Buick riviera of the same era

 

Great, one more thing to worry about now in the car. But...thanks for the heads up before the car goes up in smoke.

 

Back in the late 80's early 90's GM dropped the mechanical self adjusting mirror to an LCD style like they use now. When the old mirrors went kaput, they replaced them with the LED style. Whether or not you can find a working mechanical unit might be a bit of a challenge...
IIRC There are 3 wires:
Ground - Black
Power - Red (should go to the switch to only operate when car is on)
Green - goes to back up lights (apparently they thought it was a good idea to have it turn off when backing up.

If you have a later car with the mirror lights, then there are more wires to operate that.

Internally there is probably a small solenoid, that you might be able to rewire, or replace, but I have never messed with one to know for sure...

I used a self dimming LCD mirror on my 87 Formula (that did not come with the option) from a 1990 Buick Riviera that works flawlessly.

Technically you should be able to just unplug the mirror from the back and it would stop you from losing battery if that is an issue.

John

 

Yeah, that's what I did which solved the immediate problem. The **** side of me wants everything to be completely functional though.... I might take it apart when I get bored and try to fix it.