अक्सर पूछे जाने वाला सवाल

In the scene where Stephanie and Brady are going into town to buy warmer clothes for her; she asks him to turn on the heat and so he does. But the car isn't running, .....? Later he gets in and starts the car on and drives away. Why doesn't he start the car to turn on the heat when she asks for heat. And even if he turned on the heat when she asks, it would take awhile for the engine to heat up.