Electric heating device with integrated temperature sensor

Control circuit for operation of an electrical heating device (100), especially an auxiliary heater for a motor vehicle, whereby the heater comprises PTC heating elements and a temperature sensor (170), which measures the temperature of air flowing into the heating device. The control circuit has a memory for storing a predefined temperature threshold and a comparator for comparison of the stored temperature with the temperature measured by the temperature sensor. Dependent on the result of the comparison, current is supplied to the heating elements or not. An independent claim is made for a method for operating an auxiliary electrical heater for a motor vehicle. The invention also relates to an auxiliary electrical heater for a motor vehicle.