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Knock Sensor

KNOCK SENSOR

Description
The knock sensor is attached to the cylinder block and senses engine knocking conditions. A knocking vibration from the cylinder block is applied as pressure to the piezoelectric element. This vibrational pressure is then converted into a voltage signal which is delivered as output. It engine knocking occurs, ignition timing is retarded to suppress it.





Circuit Diagram





Troubleshooting Procedures








Harness Inspection Procedure

Sensor Inspection Procedure
1. Disconnect the knock sensor connector.





2. Measure resistance between the terminal 2 and 3.

Standard value: about 5 M ohms at 20° C (68° F)

3. If the resistance is continual, replace the knock sensor.

Tightening torque: 16 - 25 Nm (11.8 - 18.4 ft lb)