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


1. Remove No. 1 water temperature switch from water pump and No. 2 switch from lower radiator tank.
2. Place switch No. 1 in a container of water, then heat water gradually. Using a thermometer and ohmmeter, determine at what temperature continuity between terminals in coupler ceases. Continuity should cease between 146° and 170° F. If not as specified, replace water temperature switch.
3. Place switch No. 2 in a container of water, then heat water gradually. Using a thermometer and ohmmeter, determine at what temperature continuity exists between terminals. There should be continuity at 65° to 79° F and no continuity at all other temperatures. If not as specified, replace water temperature switch.