Knock Sensor: Description and Operation

DESCRIPTION
The knock sensor detects abnormal vibration (spark knocking) in the engine. The sensor is mounted in the engine block near the cylinders. The sensor produces an AC output voltage which increases with the severity of the knock. This signal voltage is input to the PCM. The PCM then adjusts the Ignition Control (IC) timing to reduce spark knock. PCM to utilizes the KS signal to diagnose the KS and circuitry. DTC P0325 and P0327 are designed to diagnose the knock sensors, and related wiring, so problems encountered with the KS system should set a DTC.