Visual/Physical Inspection
WARNING: This page is about a different car, the 2002 Oldsmobile Bravada, 2002 GMC Envoy XL, 2002 GMC Envoy, and 2002 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.
Inspect for aftermarket devices which could affect the operation of the Cooling System. Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.