Operation CHARM: Car repair manuals for everyone.

Knock Sensor: Testing and Inspection

The Tech 1 scan tool will have three positions to check for diagnosing this circuit. Knock signal is used to monitor the input signal from the knock sensor (KS). This position should display "YES" to indicate knock is being detected. Knock retard is the indication of how much the Powertrain Control Module (PCM) is retarding the spark. KS activity is used to monitor the AC signal of the KS circuit by displaying the varying activity in counts.

Diagnostic Trouble Code (DTC) 43 is designed to diagnose the knock sensor and wiring, so problems encountered with this circuit should set the code. However, if DTC 43 is not set, but the Knock Sensor (KS) system is suspected because detonation was the customer's complaint, refer to CHART C-5. Testing and Inspection