P0325

Diagnostic Chart:

Schematic:

The knock sensor system detects for an engine detonation. The knock sensor produces a voltage signal. The amplitude and the frequency of the AC voltage signal is dependent upon the knock level being detected. This signa then travels to the KS module that is an internal part of the PCM. If knock is detected, the PCM will retard the spark timing based on the signal from the knock sensor. The PCM has the ability to learn spark retard. If knock is present long enough a reduced power condition may result due to maximum spark retard. The spark compensating cells will eventually learn back (0) when knock condition is corrected. The knock sensor cannot differentiate between spark knock and other similar engine noises. This DTC will set when either circuit is open, shorted to ground, or shorted to voltage.

DTC PARAMETERS
DTC P0325 will set if Knock Sensor (KS) voltage is not within normally expected ranges for 14 seconds and the following conditions are met:
^ Engine run time is greater than 20 seconds.
^ Engine coolant is greater than 56°C (133°F).
^ Engine speed is between 1800 and 2400 rpm.
^ MAP is greater than 34 kPa.
^ No Throttle Position (TP) sensor DTCs are set.
^ Engine vacuum is between 34 and 45 kPa.

IMPORTANT: The knock circuit is continuously monitored for these parameters.

DIAGNOSTIC AIDS
^ Check and correct abnormal engine noise before using this diagnostic chart.
^ Check knock sensor torque [25 N.m (19 ft-lbs)].
^ Check that knock sensor mounting location is free of debris.