Trouble Code Charts

WARNING: This page does not describe the selected car, but rather 26 other vehicles, including the 1993 GMC Yukon, 1993 GMC Vandura Special, 1993 GMC Vandura, 1993 GMC Value Van, and 1993 GMC Suburban. However, it is still accessible from the selected car via links, so may be relevant.

The following diagnostic flow charts and circuit schematics are provided courtesy of General Motors Corp.

NOTE: Some charts require the use of a bidirectional (Tech 1) scan tester. If a bidirectional scan tester is not available, the PCM/TCM-controlled relays and solenoids may be energized by grounding ALDL test terminal "B" with ignition on and engine off.