Circuit/System Verification
WARNING: This page is about a different car, the 2008 GMC Sierra, 2008 GMC Cab & Chassis Sierra, 2008 Chevrolet Silverado, and 2008 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
IMPORTANT:
Determine the ambient temperature by using an accurate thermometer.
- If the ignition has been OFF for greater than 10 hours, determine which EGR temperature sensor is skewed by comparing EGR temperature Sensor 1 and 2 parameters to the ambient temperature with a scan tool. The readings should be within 11°C (20°F) of each other, and also the ambient temperature.
- Engine running, observe the scan tool EGR temperature Sensor 1 and 2 parameters. The readings should be between -39 to +400°C (-38 to +752°F), depending on the current ambient temperature and the vehicle operating conditions
- Engine running, observe the DTC information with a scan tool. DTC P040F should not set.
- 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.