Knock Sensor: Testing and Inspection

DIAGNOSIS
Scan Tool
The Tech 1 scanner has several positions to check for diagnosing Knock Sensor (KS) circuit. "Knock signal" is used to monitor the input signal from the knock sensor. This position should display "YES" to indicate when a knock is being detected. Knock retard is the indication of how much the Engine Control Module (ECM) is retarding the spark.

Diagnostic Charts
Diagnostic Trouble Code (DTC) 43 is designed to diagnose the knock sensor circuit. Problems encountered with this circuit should set DTC 43. However, if no DTC 43 was set but the KS system is suspected, refer to Chart C-5 Knock Sensor System Check. Chart C-5 Knock Sensor (KS) System Check