DTC P0325: Knock Sensor Module Circuit: Description

Powertrain Control Module (PCM) uses a knock sensor to detect engine detonation, or spark knock. Knock sensor produces an AC signal at all engine speeds and loads. The PCM makes adjustments to spark timing based on the amplitude and frequency of knock sensor signal. The PCM uses the knock sensor to calculate amount of normal engine noise (a noise channel) for a wide range of engine speeds and loads. The PCM compares actual knock sensor signal to learned noise channel. DTC P0325 will set if PCM detects a malfunction in the integrated knock sensor diagnostic circuity that will not allow proper diagnosis of knock sensor system.