AIR HEATER UNIT FOR MOTOR VEHICLE AND AIR HEATER SYSTEM FOR MOTOR VEHICLE

A purpose is to provide an air heater unit for a vehicle and an air heater system for a vehicle, capable of easily controlling energization to an air heater. An air heater system 200 for a vehicle includes an air heater 101 having an electrothermal heating element 120 and a semiconductor switch connected to the electrothermal heating element 120 in series to control the energization to the electrothermal heating element. The semiconductor switch 110 is a semiconductor switch having a current detecting function provided with a fourth connector pin 114 (a terminal for current detection) to detect a current which flows in the electrothermal heating element 120.