Diagnostic Aids

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