Possible Causes
- Electrical Cause
- Mechanical Cause
- Monitor Description
- The powertrain control module will set a DTC if the engine off time calculated from the global time in the instrument cluster/body control module is less than 1 hour, when the shutdown temperature was fully warm and the engine coolant temperature at start is significantly cooled down to ambient temp
- Prioritized List of Possible Causes
- Vehicle battery has been isolated and the global time does not increment. Rapid engine temperature cooling (for example, warm coolant has been replaced with cold coolant) with a rapid ambient temperature increase
- Powertrain control module power or ground circuit open circuit, high resistance
- Engine coolant temperature sensor circuit short circuit to ground, short circuit to power, open circuit, high resistance
- Ambient air temperature sensor circuit short circuit to ground, short circuit to power, open circuit, high resistance