200 Quattro Wagon L5-2226cc 2.22L SOHC Turbo (MC) (1989)
Coolant Temperature Sensor/Switch (For Computer): Description and Operation
Temperature Safety Switch
Temperature Sensor (Overheat Sensor - Multi Function)
The temperature safety switch is a multi-function temperature sensor with a negative temperature coefficient thermistor (resistance decreases as
temperature increases). It is used to indicate engine temperature to the ECU for the temperature gauge, engine overheat warning light, A/C compressor
cut-out (in case of engine overheat), and turbo boost pressure regulation. If the engine overheats (coolant temperature greater than 119~C (245~F), the
ECU will not allow turbo boost. For more information on boost pressure regulation, see WASTEGATE FREQUENCY VALVE.