Diagnostic Aids (Knock Sensor With Spark Control Module)

WARNING: This page does not describe the selected car, but rather 18 other vehicles, including the 1995 GMC Vandura Special, 1995 GMC Vandura, 1995 GMC Suburban, 1995 GMC Rally Camper Special, and 1995 GMC Rally. However, it is still accessible from the selected car via links, so may be relevant.

Code 43 can be caused by a faulty knock sensor connection at ESC module or engine control module. Also, check controller-to-control module signal line for an open or short to ground.

Fig 1: Code 43 Schematic ("P" Series) Knock Sensor With Spark Control Module

Fig 2: Code 43 Schematic ("C" & "K" Series) Knock Sensor With Spark Control Module

Fig 3: Code 43 Flow Chart (All Models) Knock Sensor With Spark Control Module