Coolant Temperature Sending Unit

Partially drain cooling system. Disconnect coolant temperature sending unit connector. Remove sending unit from vehicle. Warm sending unit in water. Ensure resistance decreases with increase of temperature. See Fig 1 . Check sending unit resistance as temperature changes. See COOLANT TEMPERATURE SENDING UNIT RESISTANCE  table. If resistance is not as specified, replace coolant temperature sending unit.

Fig 1: Testing Coolant Temperature Sending Unit (Typical)

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