Diagnostic Aids

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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 ("C" & "K" Series) Knock Sensor With Spark Control Module

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

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