Backing out of garage, the driver began to smell acid and burnt electronics from the back of car. After driving back home from work the driver inspected the car. The back driver side door reeked of burnt electronics and the entire car had an acid smell. After consulting Tesla, the first Tesla maintenance worker noticed the entire inside of the door had melted and all electronics were fried. He claimed he had never seen this before. The second maintenance worker came with parts and determined the window module had overheated and caught fire. The fire melted many components inside the door. A brand new 2021 Tesla Model Y should not spontaneously catch fire. Especially if it is residing inside the garage of a house. After replacing all the components, Tesla deemed the car safe to drive. Yet, a couple days later they requested we bring the car in so that they could replace the computer that controls the left side of the car to do more research and find the 'root' cause of the fire. There were no warnings for the driver, nor was the driver using that window module. We have not driven the car since as we feel unsafe in the vehicle.