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Circuit/System Verification

WARNING: This page is about a different car, the 2011 Chevrolet Volt. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition ON, observe the DTC information with a scan tool. DTC P00B3, P00B4, P00B6, P0117, P0118, P0480, or P0481 should not be set.
  2. Verify the coolant in the radiator surge tank is at the correct level and there are no engine coolant leaks. Refer to Cooling System Draining and Filling  and Loss of Coolant .
    3. NOTE: Depending on ambient temperature, it may take up to 4 min for the temperature to increase greater than the specified value.
  3. Increase the Throttle speed to WOT. Observe the scan tool ECT sensor parameter. The temperature should increase to greater than 102°C (215°F).
    • If less than the specified value, replace the Engine Coolant Thermostat.
  4. Command the Engine Coolant Thermostat Heater to 0 percent with a scan tool. Increase the Throttle speed to WOT. Observe the scan tool ECT sensor parameter. The temperature should increase to greater than 102°C (215°F).
    • If less than the specified value, replace the engine coolant heater.
  5. Operate the vehicle within the conditions for running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.
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