Diagnostic Tests
- 1)
COOLANT LEVEL WARNING: Never open the cooling system when the engine is hot. The system is under pressure. Extreme burns or scalding may result. Allow the engine to cool before opening the cooling system.
Check coolant mixture and the cooling system level.
If coolant level is low, check for visible leaks or perform a pressure test on the coolant system.
Was the coolant level low and where any leaks found.
Yes
- Repair the coolant leak and/or fill coolant to the proper level.
- Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
No
- Go To 2).
- 2)
COOLANT TEMPERATURE
Start engine and let the vehicle warm up to operating temperature.
WARNING: When the engine is operating, do not stand in a direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing.With the scan tool in Inputs/Outputs, monitor the Coolant Temperature Sensor value.
Does the coolant temperature increase normally and display within 5 degrees of Calculated Coolant Temp.
Yes
- Refer to the INTERMITTENT CONDITION diagnostic procedure.
- Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
No
- Replace thermostat and fill coolant level to proper level.
- Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .