Engine - Coolant Temperature Sensor/Switch: Testing and Inspection

Fig. 18 Water temperature switch test:

Fig. 19 Water temperature sensor resistance specifications:

Perform water temperature sensor test as illustrated in Fig. 18. If resistances are not as specified, check sensor as follows:
1. Position water temperature sensor in a container of water and measure resistance when heated to various temperatures, Fig. 19.
2. If resistance readings are within specifications, check sensor harness and correct as necessary. If readings are not within specifications, replace sensor.