Circuit/System Verification

CAUTION: Under pressure, the temperature of the solution in the radiator can be considerably higher, without boiling. Removing the radiator cap while the engine is hot (pressure is high), will cause the solution to boil instantaneously, with explosive force. The solution will spew out over the engine, fenders, and the person removing the cap. Serious bodily injury may result. Flammable antifreeze, such as alcohol, is not recommended for use at any time. Flammable antifreeze could cause a serious fire.

Turn OFF the ignition.
Inspect the cooling system surge tank for the proper engine coolant level. Refer to Cooling System Leak Testing (Powertrain) or Cooling System Leak Testing (Charge Air Cooling) and Cooling System Draining and Filling (Static Fill) or Cooling System Draining and Filling (GE 47719) .
Ignition ON, observe the ECT Sensor parameter. The reading should be between -39 to +120°C (-38 to +248°F) depending on the current ambient temperature and the vehicle operating conditions.
Use the scan tool to verify the proper operation of the engine cooling system fans.
Engine running, observe the DTC information with a scan tool. DTCs P0117 or P0118 should not set.
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.