Diagnostic Aids

WARNING: This page does not describe the selected car, but rather 24 other vehicles, including the 1992 GMC Yukon, 1992 GMC Vandura Special, 1992 GMC Vandura, 1992 GMC Value Van, and 1992 GMC Suburban. However, it is still accessible from the selected car via links, so may be relevant.

Check all connections, especially those at transmission pass-thru connector. If code is intermittent, see INTERMITTENTS in TESTS W/O CODES article in this section. While Code 24 is set, scan tester will display an RPM derived from input speed. If input speed sensor is not operational at start-up, this can cause VSS to read zero.

Fig 1: Code 24, Schematic, Vehicle Speed Sensor (VSS)

Courtesy of GENERAL MOTORS CORP.

Fig 2: Code 24, Flow Chart, Vehicle Speed Sensor (VSS)

Courtesy of GENERAL MOTORS CORP.