I cold started the engine from inside the house and when I opened the back passenger door there was smoke coming from behind the rear seat in the back area. I couldnt get to where the smoke was coming from but from the smell it was wire related. I quickly went around to the driver side and turned on the truck and quickly turned it off. About 10-30 minutes later the ring camera showed the rear window of my truck shatter due to this incident in which I was informed that the rear auto defrost turns on due to a malfunction. I put a claim through my insurance and got the window fixed but I am still worried that this issue may happen again. I hope that by informing you of this situation going forward you can help others including myself be aware of this problem and how we can fix it. Thank you for your time and I like to say I love ford trucks and plan on staying a loyal customer.