FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Air Temperature Sensor ( Ambient / Intake ): Description and Operation




GF07.04-P-6070KE Component Description For The Intake Air Temperature Sensor
- ENGINE 271.921 /944 /946 /948 up to Model Year 8
- ENGINE 271.940 in MODEL 203 up to Model Year 8
- ENGINE 271.940 in MODEL 209
- ENGINE 271.941 /955 /956

Location







B17 Intake air temperature sensor

The temperature sensor is located behind the throttle valve actuator (M16/6).

Task
The temperature sensor detects the suction/charge air temperature and sends a corresponding voltage signal to the ME control unit (N3/10).

Function







1, 2 Connection pins
3 Plug connector
4 NTC resistor
B17 Intake air temperature sensor

The NTC resistor integrated in the temperature sensor alters its electrical resistance in line with the suction/charge air temperature.
The ME control unit applies a sensor voltage of 5 V and evaluates the signal voltage in accordance with the suction/charge air temperature.

NTC means "Negative Temperature Coefficient", which means: The electrical resistance falls as the temperature rises (heat conductor).

The connection (polarity) of the connection pins is random.