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Circuit/System Testing

WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2007 GMC Yukon XL, 2007 GMC Yukon, 2007 Chevrolet Tahoe, 2007 Chevrolet Suburban, and 2007 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
  1. Test the thermostat for correct operation. Refer to Thermostat Diagnosis .
  2. Test the engine cooling system for overheating. Refer to Engine Overheating .
  3. Inspect the water pump and coolant flow for correct operation. Refer to Water Pump Replacement (RPOs LY2/LC9/LY5/LMG)  or Water Pump Replacement (RPOs LY6/L76/L92) .
  4. Inspect the engine mechanical for worn/leaking/cracked cylinder heads and engine block. Refer to Coolant in Combustion Chamber and Coolant in Engine Oil .
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