Circuit Description

WARNING: This page is about a different car, the 2003 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.

The Knock Sensor (KS) system enables the Engine Control Module (ECM) to control the ignition timing for the best possible performance while protecting the engine from potentially damaging levels of detonation. The KS system uses 2 sensors. KS 1 is located on the right side of the engine or the rear of the engine compartment. KS 2 is located on the left side of the engine or the front of the engine compartment. The KS produces an AC voltage signal that varies depending on the vibration level during engine operation. The ECM adjusts the spark timing based on the amplitude and the frequency of the KS signal. The ECM receives the KS signal through a signal circuit. The KS ground is supplied by the ECM through a low reference circuit. The ECM learns the minimum and maximum amplitude of the noise the engine produces. The ECM should monitor a normal KS signal within the voltage range. If the ECM detects the KS signal exceeding the voltage range a DTC sets. DTC P0328 refers to KS 1 and P0333 refers to KS 2.