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Knock Sensor: Testing and Inspection

KNOCK SENSOR (KS) INSPECTION [AJ]

NOTE: Perform the following inspection only when directed.

Resistance Inspection

1. Disconnect the negative battery cable.
2. Disconnect the KS connector.




3. Measure the resistance between KS terminals A and B using an ohmmeter.
- If the KS is okay, but the PID value is out of specification, perform the "Circuit Open/Short Inspection".
- If not as specified, replace the KS.

Specification: Approx. 4.87 megohms (20 degrees C {68 degrees F})

Circuit Open/Short Inspection




1. Disconnect the PCM connector.
2. Inspect the following harness for open or short circuit. (Continuity check)

Open circuit
- KS terminal B and PCM terminal 2AC
- KS terminal A and PCM terminal 2AF

Short circuit
- KS terminal A and power supply
- KS terminal A and body ground
- KS terminal B and power supply
- KS terminal B and body ground