P0050 or P0056
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.
- The ignition 1 signal parameter is between 11-18 volts.
- The engine speed is more than 400 RPM.
- DTCs 0050 or P0056 run once per drive cycle when the above conditions are met.