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Knock Sensor: Testing and Inspection

KNOCK SENSOR (KS)

DESCRIPTION
knock sensor is a piezoelectric device attached to cylinder block that senses pressure from engine knock conditions. This vibrational pressure is then converted into a voltage signal which is delivered as output. If engine knock occurs, ignition timing is retarded to suppress it.

Circuit Diagram (Knock Sensor):






Harness Connector:






Troubleshooting Procedures:






TROUBLESHOOTING HINTS
1. The MIL is ON or the DTC is displayed on the HI-SCAN (PRO) under the following condition:
1. When the knock sensor signal is not detected, even though the engine is in an overload condition.
2. When the knock sensor signal is abnormally low.

Step 1 - 2:




HARNESS INSPECTION PROCEDURES (KNOCK SENSOR)