The knock sensor installed on the cylinder block reacts to high-frequency vibrations of the cylinder block and converts them into electrical signals, the value of which increases with increasing detonation. Based on these signals, the ECM retardes the ignition timing, thereby eliminating detonation.
Examination
1. Disconnect the connector from the knock sensor and measure the resistance between terminals 1 and 2 of the connector. Resistance: more than 5 mOhm at 20°C.
2. If the resistance is different from the specification, replace the sensor. Tightening torque: 16–25 Nm.
3. Measure the capacitance between terminals 1 and 2 of the connector. Capacitance: 800-1600 pF.