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Home >> Geo >> 1989 >> Spectrum L4-91.5 1.5L >> Repair and Diagnosis >> Engine, Cooling and Exhaust >> Cooling System >> Engine - Coolant Temperature Sensor/Switch >> Radiator Cooling Fan Temperature Sensor / Switch >> Testing and Inspection
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Radiator Cooling Fan Temperature Sensor / Switch: Testing and Inspection


1. Drain cooling system and remove thermosensor from radiator.
2. Connect an ohmmeter between sensor terminals.
3. Heat thermosensor in suitable solution while observing ohmmeter.
4. Meter should indicate continuity when temperature reaches 186-192°F.
5. Allow sensor to cool while observing meter. Meter should indicate no continuity as temperature drops below 178-183°F.
6. If sensor fails to operate as outlined, sensor is defective.

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