190E 2.3 (201.028) L4-2.3L (102.985) (1987)
Ambient Temperature Sensor / Switch HVAC: Description and Operation
Outside Temperature Sensor
Temperature Sensor Locations
PURPOSE
The outside (ambient) temperature sensor, which is located on the top of the evaporator housing, sends outside temperature information to the
push-button control unit for calculation of blend air flap position and other outputs.
CONSTRUCTION
The outside temperature sensor is a negative temperature coefficient (NTC) type resistor. As the surrounding temperature increases the resistance
decreases.
OPERATION
The outside air produces a resistance value in the sensor circuit. The resulting current flow in the sensor circuit is recognized by the TCC control unit as
a measurement of the outside air temperature.