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Coolant Temperature Sensor/Switch (For Computer): Testing and Inspection

Note: Applies to Engine Coolant Temperature Sensor (ECTS) and Intake Air Temperature Sensor (IATS).

- The IATS should be tested in air; the ECTS can be tested in water.
- The temperature of the component should be measured with an accurately calibrated thermometer. Be sure that the temperature of the component has stabilized. Using a DMM set to ohms measure the resistance across the connector blades.

Temperature Chart:





- Compare the reading obtained to chart; the resistance should be within the band.
- If the reading falls outside the band, recheck temperature and resistance measurement. Check each pin to the component case, the resistance should be very high (infinity).
- Replace components which fall outside of the tolerance.