Circuit/System Verification
- Engine Running, observe the DTC information with a scan tool. DTC P00B3, P00B4, P00B6, P0117, P0118, P0597, P0598, and P0599 should not be set.
- If a DTC is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.
- Verify the coolant in the radiator surge tank is at the correct level and there are no engine coolant leaks. Refer to Cooling System Draining and Filling and Loss of Coolant .
- Verify the engine cooling fan operates. Refer to Cooling Fan Inoperative (LUJ or LUV) or Cooling Fan Inoperative (2H0) .
- Engine idling for 15 minutes with the A/C OFF.
- Command the Engine Coolant Thermostat Heater to 100 percent with a scan tool. Increase the engine speed to 3, 000 RPM. Observe the scan tool ECT sensor parameter. The temperature should decrease to less than 85°C (185°F).
- Operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.
NOTE:
Depending on ambient temperature, it may take up to 4 minutes for the temperature to decrease less than the specified value.