Defroster/defogger/hvac System problems of the 2016 GMC Sierra 1500

The contact owns a 2016 GMC Sierra 1500. The contact stated that while idling in the drive-through at a pharmacy, the contact noticed smoke coming from the rear window, and the rear window shattered. The contact stated that the defroster was activated at the time of the failure. There was no injury sustained. The contact deactivated the defroster and drove to the residence, where the contact disconnected the defroster fuse. The contact related the failure to customer satisfaction program number: n192265660 (rear window defroster thermal events). The vehicle was not diagnosed or repaired by an independent mechanic. The manufacturer was notified of the failure and referred the contact to the NHTSA hotline to report the failure. The failure mileage was approximately 139,250.