P0050 or P0056
WARNING: This page is about a different car, the 2009 GMC Sierra and 2009 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
- The ECM detects that the affected HO2S heater low control circuit is not within a specified range at engine start-up.
- DTCs P0050 or P0056 set within one second when the above condition is met.