Diagnostic Aids

WARNING: This page does not describe the selected car, but rather 24 other vehicles, including the 1993 Pontiac Trans Sport, 1993 Oldsmobile Silhouette, 1993 Oldsmobile Bravada, 1993 GMC Vandura, and 1993 GMC Value Van. 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 ECM. Also, check controller-to-ECM signal line for an open or short to ground.

Fig 1: CODE 43, Schematic, ESC W/ Spark Control Module (3.1L)

Fig 2: CODE 43, Schematic, ESC W/ Spark Control Module (Exc. 3.1L)

Fig 3: CODE 43, Flowchart, ESC W/ Spark Control Module