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Ambient Temperature Sensor / Switch HVAC: Testing and Inspection




Wiring Diagram:





1. Remove front radiator grille.
2 Disconnect ambient temperature sensor connector.
3. Check resistance between terminals 1 and 2 of ambient temperature sensor connector at each temperature.

RESISTANCE:

At 25°C (77°F) 1.6 - 1.8 K Ohms
At 50°C (122°F) .05 - .07 K Ohms


HINT: As the temperature increases, the resistance decreases.

4. If the sensor fails this test replace the room temperature sensor.