Conditions For Running DTC

WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2003 GMC Yukon XL, 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Suburban, and 2003 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.

DTCs P0101, P0102, P0103, P0120, P0335, P0336, or P0742 are not set.
The vehicle speed is more than 10 MPH.
The engine load is less than 60 percent.
The engine misfire is detected and DTC P0300 set.
The engine speed is less than 3200 RPM.