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.

Verify a clean, tight connection for ground circuit No. 413. An open circuit at sensor signal terminal or ground terminal will result in a Code 13.

CODE 13 ECM TERMINAL & CIRCUIT WIRING IDENTIFICATION

Application	ECM Terminal	Wire Color
All With 4L80-E Transmission
Oxygen Sensor Signal	C14	Purple
Oxygen Sensor Ground	C13	Tan
All Others Except 3.8L
Oxygen Sensor Signal	D7	Purple
Oxygen Sensor Ground	D6	Tan

Fig 1: Code 13, Schematic, Open Oxygen Sensor Circuit

Courtesy of GENERAL MOTORS CORP.

Fig 2: Code 13, Flow Chart, Open Oxygen Sensor Circuit

Courtesy of GENERAL MOTORS CORP.