Question on heated outside mirrors
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Question on heated outside mirrors
So the one ice storm we had this winter, my driver side mirror did not clear the ice like I thought it should. The rear window cleared the passenger side either cleared or I never noticed if it was iced in the first place.
So on a clear of ice and frost day but 24 degrees F outside. I took my IR temp gun and both mirrors were at ambient 25, I turned on and operated for a while with the rear defrost selected and checked again. The drivers mirror went up 10 degrees F above ambient, but the passenger side went up 20 degrees ambient. Is it possible that the element in the glass can get resistive or break an element and be weaker? Too cold out to pop off the trim and check voltages to the unit, cold here not but not wet and frosty.
So on a clear of ice and frost day but 24 degrees F outside. I took my IR temp gun and both mirrors were at ambient 25, I turned on and operated for a while with the rear defrost selected and checked again. The drivers mirror went up 10 degrees F above ambient, but the passenger side went up 20 degrees ambient. Is it possible that the element in the glass can get resistive or break an element and be weaker? Too cold out to pop off the trim and check voltages to the unit, cold here not but not wet and frosty.
in the house
Joined: Jul 2010
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From: Kansas
Anything is possible.
I have never really looked to see how a heated mirror works, frankly. How old is your vehicle? What I do know is on all my vehicles with heated mirrors, even if it is well below freezing, the mirrors clear within a couple of minutes, will literally be dripping.
I have never really looked to see how a heated mirror works, frankly. How old is your vehicle? What I do know is on all my vehicles with heated mirrors, even if it is well below freezing, the mirrors clear within a couple of minutes, will literally be dripping.
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2018 XTR 3.5L I never looked at my own posts I just assumed that if I put my vehicle description in my profile it would appear to everyone on a tag line on the posts I make.
It does not so I do not know how people get their vehicle info on every post at the bottom.
It does not so I do not know how people get their vehicle info on every post at the bottom.
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From: Memphis, TN, Earth, Milky Way
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So today I popped off the cover on the inside of the door to get to the mirror electrical connections. I found the wire that switched the voltage when the rear defrost button. One the passenger working side the resistance from that pin to chassis ground was around 400 OHMs and on the driver's non working side it was around 7 OHMs which makes me suspect the mirror is shorted but not quite a dead short to blow a fuse. 14v over 7 OHMs would still only be a 2a draw. I felt the mirror on the passenger side and I could feel heat above the temp of my hand, and the drivers side was cold. So I ordered a replacement aftermarket matching glass.