Circuit/System Verification
WARNING: This page is about a different car, the 2012 GMC Yukon, 2012 Chevrolet Tahoe, and 2012 Cadillac Escalade. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, open the hood to disable the Auto-Stop function. Refer to Hybrid Modes of Operation Description .
- Ignition ON, verify the scan tool hood position parameter displays Open.
- If the hood position does not display Open, refer to Diagnostic Trouble Code (DTC) List - Vehicle for DTC P254F.
P0443
- Ignition ON, engine OFF, you should hear a clicking sound when the EVAP purge solenoid valve is commanded to 50% with a scan tool. The clicking sound should stop when the EVAP purge solenoid valve is commanded to 0%. The rate at which the valve cycles should increase when the commanded state is increased, and decrease when the commanded state is decreased.
- 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.
P0449
- Ignition ON, engine OFF, command the EVAP vent solenoid ON (Not Venting) and OFF (Venting) with a scan tool.
- Listen for a click when the valve operates. Verify that both the ON (Not Venting) and the OFF (Venting) states are commanded while watching their parameter status.
- EVAP Vent Solenoid Valve Control Circuit High Voltage Test Status
- EVAP Vent Solenoid Valve Control Circuit Low Voltage Test Status
- EVAP Vent Solenoid Valve Control Circuit Open Test Status
Each parameter should display OK or Not Run.
- Operate the vehicle within the conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.