Engine Fails to Reach Normal Operating Temperature

1. Verify that the cooling system is properly filled.
2. If the complaint is a low temperature gage reading, check the temperature gage for proper operation. Connect a scan tool to the vehicle and read the system temperature. Compare this reading to the temperature gage. Replace the gage or switch if necessary.
3. If the complaint is no heat from the Heating and Air Conditioning system, refer to No Heat Diagnosis in Air Conditioning.
4. Verify proper thermostat operation. Refer to Thermostat Diagnosis.