Self-Diagnostic System: Notes
WARNING: This page does not describe the selected car, but rather 20 other vehicles, including the 1993 GMC Yukon, 1993 GMC Vandura Special, 1993 GMC Vandura, 1993 GMC Suburban, and 1993 GMC Rally Camper Special. However, it is still accessible from the selected car via links, so may be relevant.
The 6.2L light duty emission DEC system includes a self-diagnostic system which can determine input signal circuit malfunctions. Input signal circuits determine engine function control.