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Test Z: The Engine Coolant Over Temperature Warning Indicator Is Never/Always On

PINPOINT TEST Z: THE ENGINE COOLANT OVER TEMPERATURE WARNING INDICATOR IS NEVER/ALWAYS ON


Z1-Z4:






Normal Operation
The powertrain control module (PCM) receives the engine coolant temperature status through hardwired circuitry to the cylinder head temperature sensor. The instrument cluster receives the engine coolant temperature data from the PCM over the controller area network (CAN). The instrument cluster monitors the engine coolant temperature data received from the PCM and when the engine coolant temperature is high, the coolant over temperature warning indicator illuminates.

Possible Causes
- PCM
- instrument cluster