Circuit Description

The powertrain control module (PCM) monitors a knock sensor (KS) to determine if detonation is present. The KS produces an AC voltage at all engine speeds and loads. The PCM then adjusts the spark timing based on the amplitude and frequency of the KS signal. The PCM uses the KS signal to calculate the average voltage and then assigns a voltage range value. The PCM should monitor the KS signal within the assigned voltage range. This DTC will set if the KS signal is outside the assigned voltage range or the KS signal is not present.