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Coolant Temperature Sensor / Switch HVAC: Testing and Inspection





Inspection

1. Ignition "ON"
2. Using the multi-tester, Measure resistance between terminal "1" and "2" of water temperature sensor.




[Specification]





3. If the measured resistance is not specification, substitute with a known-good water temperature sensor and check for proper operation.
4. If the problem is corrected, replace the water temperature sensor.

NOTE:
Negative type thermistor that resistance will rise with lower temperature, and reduce with higher temperature.