GM Service Manual Online
For 1990-2009 cars only

Important: Review the Cooling System Description and Operation in order to familiarize yourself with the system functions.

Visual/Physical Inspection

    • Inspect for aftermarket devices which could affect the operation of the system. Refer to Checking Aftermarket Accessories in Wiring Systems.
    • Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.
    • Inspect all related ground points for being clean and tight.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom:

    •  Engine Overheating
    •  Loss of Coolant
    •  Thermostat Diagnosis
    •  Engine Fails To Reach Normal Operating Temperature
    •  Cooling System Draining and Filling

Refer to Symptoms - HVAC Systems - Manual in HVAC Systems -- Manual for diagnosis of the electric cooling fan.