Abstract: A control device for a heater in a vehicle. The control device has a thermostatic switch to turn the heater on when the air temperature drops to a first value that is around the temperature at which the engine will just easily start. A secondary heater is provided within the device, turned on when the heater is turned on, to cause the switch to turn the heater off when the switch is heated by the secondary heater to a second temperature that correlates to an outside temperature at which the engine starts more easily.