Harold Harkonen

Another design issue that I see is that GM is trying to protect 3 separate defroster grids on the sliding rear window with one fuse and wire connection to the fuse panel instead of using 3 separate wires with smaller fuses. Might have been a cost cutting measure but violates a basic design rule in my opinion.

2015 Cadillacs were recalled for the same thing but of course all they did was disable the auto defrost mode. I am sure the relay doesn't cycle based on a sensor but it just set to a timer. Greasing a connection inside the truck isn't going to do much, there is no extra corrosion there to make a hot spot worse. The connection obviously isn't designed properly for the service. The more people complain to GM and NHTSA then the more likelihood something will get done before a baby in a rear car seat is hurt or killed by this defect. Not a waste for most people searching for this problem. Manufacturers need to fix their design defects not worry about goddamn lawyers and insurance. They will just keep ignoring if people don't know where to complain.

My opinion is that it is a programming glitch that keeps the relay on too long in certain situations, can't protect against that with a fuse. GM would have to fix that and issue a recall. A poor design in my opinion when a fuse can't be applied properly to prevent a fire....

I finally got my window repaired by the dealer at no cost. They claimed GM had not found the cause of the wiring fire and window shattering but had another truck with the same issue where the window didn't break and they have sent the window away for analysis. Being a curious electrical engineer I believe the problem could be either a sticking defogger relay that I assume is supposed to cycle the current to the defogger, or a programming glitch in the computer that controls the relay. I tested the relay on the bench but it did not stick with multiple operations. I have disabled the automatic window defog on remote start (since I think that is a possible source for a programming problem). Hopefully GM figures it out soon and refunds the money that people have paid out to fix the damage on their own.!

It has been to the dealer twice now for GM's investigation. They said today that GM asked them to look at the rest of the wiring that feeds the defroster to look for any more damage but they didn't find any. Still a shrink wrap window on the truck while I wait. The dealer said they had only seen this on 2015's so far, not a 2017. I believe that either the defogger relay sticks and doesn't shut of the circuit as it cycles or there is some sort of programming glitch. Time will tell I hope....

I am in Canada and I'm not sure if we have a similar site with Transport Canada. I did send a message to GMC on Messenger and they seemed very interested. I haven't had a phone call yet though... I notice my truck was made in Mexico....

It was the same for me, at first I thought it was my laptop battery and when I saw how hot the wiring connection on the window was getting I rushed back to shut off the engine before it started a fire.. I could probably put the fuse back in and turn it back on.....

No problem, by the time I opened the back door the connection was glowing red hot and the trim was melting and smoking. I just heard from a friend that he knows someone that had it happen just last week as well on their Sierra. I see that GM had a recall on 2015 Cadillac CTS's for this very same issue.... I can't wait to hear the dealer excuses since my warranty just expired 6,000 miles ago..... I assume this will likely become a more widespread problem soon.

This just happened to me last night on my 2017 Sierra 1500! I remote started my truck when leaving a store and when I got into the truck a minute later I could smell smoke. I thought it was my laptop battery but then I saw the connection to the drivers side window defroster glowing red hot and burning the window trim. I shut the truck off and while I was sitting there I heard what sounded like a gun shot as the window exploded. Obviously a wiring defect. We'll see what the dealer has to say. clearly nothing to do with an impact from anything lol.