Circuit/System Verification
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2008 GMC Yukon XL, 2008 GMC Yukon, 2008 Chevrolet Tahoe, 2008 Chevrolet Suburban, and 2008 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
- Start and idle the engine.
- Allow the engine to reach normal engine operating temperature. The engine should idle smoothly, without any misfires. If the engine misfires, refer to DTC P0300-P0308 .
- Monitor the cylinder deactivation system data parameters with a scan tool.
- Road test the vehicle under light throttle and load conditions that will allow the engine to command V4 mode. If all enabling conditions are met for cylinder deactivation, and if no internal engine hydraulic/mechanical fault conditions are present, the ECM will continue with V4 mode operation.
- 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.