The contact owns a 2015 Chevrolet Silverado 1500. The contact stated that while parking, the passenger in the rear seat noticed that there was smoking coming from the rear of the vehicle. The contact mentioned that the rearview defroster was operating and there was a blue smoke coming from the rear window. The contact stated that the smoke was extinguished by opening up the rear doors. The dealer was not contacted. The vehicle was not repaired. The manufacturer was notified of the failure. The approximate failure mileage was 42,000.