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Knock Sensor: Testing and Inspection

DIAGNOSIS
The Tech 1 tool has two data displays to check for diagnosing this circuit. "KNOCK SIGNAL" is used to monitor the input signal from the knock sensor(s). This position will display "YES" when knock is being detected. "KNOCK RETARD" is the amount of degrees the PCM is retarding the spark timing.

DTC P0325 is designed to diagnose the knock sensor(s) and wiring, so problems encountered with this circuit should set the DTC. However, if no DTC P0325 was set but the KS system is suspect because detonation was the customer's complaint, refer to Chart C-5 Knock Sensor System Check. Refer to System Diagnosis / Diagnostic Charts. Testing and Inspection