Thermostat: Testing and Inspection

DIAGNOSIS AND TESTING - ON-BOARD DIAGNOSTICS

All models are equipped with On-Board Diagnostics for certain cooling system components Testing and Inspection. If the powertrain control module (PCM) detects low engine coolant temperature, it will record a Diagnostic Trouble Code (DTC) in the PCM memory. Do not change a thermostat for lack of heat as indicated by the instrument panel gauge or by poor heater performance unless a DTC is present.