Circuit Description
WARNING: This page is about a different car, the 2003 Lexus GS 300. However, it is still accessible from the selected car via links, so may be relevant.
Knock sensors are located on front and rear left side of cylinder block. Sensor generates voltage when engine block vibrates due to knocking. If engine knocks, ECM will retard ignition timing. If DTC is set, ECM will operate in fail-safe mode (maximum timing retardation). DTC is set when there is no knock sensor signal to ECM with engine speed of 1600-5200 RPM. DTC P0325 is for knock sensor No. 1 on front of cylinder block. DTC P0330 is for knock sensor No. 2 on rear of cylinder block. See Fig 1. Possible causes are:
- Open or short in knock sensor circuit.
- Knock sensor No. 1 or 2 loose.
- Faulty ECM.