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Circuit/System Testing

WARNING: This page is about a different car, the 2009 GMC Sierra, 2009 GMC Cab & Chassis Sierra, 2009 Chevrolet Silverado, and 2009 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

Check the Water in Fuel lamp for proper operation. Refer to Water in Fuel Indicator Malfunction .

  1. Turn ON the ignition, with the engine OFF.
  2. Disconnect the fuel heater connector.
  3. With the fuel temperature above 21°C (70°F), test for continuity between the ignition 1 voltage terminal and the fuel filter/heater element housing.
    • If continuity was present, the thermostatic switch is stuck ON. Replace the fuel heater element.
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