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Home >> Jeep >> 2002 >> Grand Cherokee 4WD Limited V8-4.7L >> Repair and Diagnosis >> Heating and Air Conditioning >> Ambient Temperature Sensor / Switch HVAC >> Testing and Inspection
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Ambient Temperature Sensor / Switch HVAC: Testing and Inspection

Ambient Temperature Sensor Test
1. Turn the ignition OFF.
2. Disconnect the ATS harness connector.
3. Measure the resistance of the ATS using the following min/max values:

AMBIENT TEMPERATURE SENSOR RESISTANCE

0 °C (32 °F) 29.33 - 35.99 Kilohms
10 °C (50 °F) 17.99 - 21.81 Kilohms
20 °C (68 °F) 11.37 - 13.61 Kilohms
25 °C (77 °F) 9.12 - 10.86 Kilohms
30 °C (86 °F) 7.37 - 8.75 Kilohms
40 °C (104 °F) 4.90 - 5.75 Kilohms

The sensor resistance should read between these min/max values. If the resistance values are not OK, replace the sensor.
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