P0325 Code: Meaning, Causes, and Symptoms | OBD2 Codes
P0325 – Knock Sensor Circuit Malfunction
P0325: DIY Repairing Video Tutorial
Check out nonda Auto DIY Center for more engine error code repairing videos.
https://www.youtube.com/playlist?list=PL-Lyko0O0oxHe1AGvzwAz-wokJPXAtW97
P0325 Possible Causes
Faulty Knock Sensor
Knock Sensor circuit poor electrical connection
Knock Sensor harness is open or shorted
Faulty Engine Control Module (ECM)
P0325 Possible Symptoms
Engine Light ON (or Service Engine Soon Warning Light)
Possible Lack/Loss of Power
Description
A knocking vibration from the cylinder block is sensed as vibrational pressure by the Knock Sensor. This pressure is converted into a voltage signal and sent to the Engine Control Module (ECM). The ECM uses this signal to retard the ignition timing and protect the engine from this damaging pre-ignition. Engine knock occurs within a specific frequency range. The Knock Sensor, located in the engine block, cylinder head, or intake manifold, is tuned to detect that frequency. Inside the knock sensor is a piezoelectric element. Piezoelectric elements generate a voltage when pressure or vibration is applied to them. The piezoelectric element in the Knock Sensor is tuned to the engine knock frequency. The vibration from the engine knocking vibrates the piezoelectric element generating a voltage. The voltage output from the Knock Sensor is highest at this time.