Circuit Description
WARNING: This page is about a different car, the 2003 Lexus GS 430. However, it is still accessible from the selected car via links, so may be relevant.
Each knock sensor is fitted to the right bank and left bank of the cylinder block to detect engine knocking. Sensor contains a piezoelectric element which generates a voltage when it becomes deformed, which occurs when cylinder block vibrates due to knocking. If engine knocking occurs, ignition timing is retarded to suppress it. 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 1700-5400 RPM. DTC P0325 is for knock sensor No. 1 on left side of cylinder block. DTC P0330 is for knock sensor No. 2 on right side of cylinder block. See Fig 1. Possible causes are:
- Open or short in knock sensor circuit.
- Knock sensor loose.
- Faulty ECM.