Knock Sensor: Testing and Inspection

DESCRIPTION
The knock sensor is attached to the cylinder block. It senses engine knocking using a piezoelectric element. A knocking vibration from the cylinder block is sensed as vibrational pressure. This pressure is converted into a voltage signal and sent to the ECM.

*: Freeze frame data will not be stored in the ECM for the knock sensor. The MIL will not light for knock sensor malfunction.




DIAGNOSTIC TROUBLE CODE CONFIRMATION PROCEDURE

NOTE:
- Before performing the following procedure, confirm that battery voltage is more than 10 Volts.

WITH CONSULT
1. Turn ignition switch "ON" and select "DATA MONITOR" mode with CONSULT.
2. Start engine and run it for at least 5 seconds at idle speed.

OR

WITH GST
1. Start engine and run it for at least 5 seconds at idle speed.
2. Select "MODE 3" with GST.

OR

WITH NO TOOLS
1. Start engine and run it for at least 5 seconds at idle speed.
2. Turn ignition switch "OFF", wait at least 5 seconds and then turn "ON".
3. Perform "Diagnostic Test Mode II (Self-diagnostic results)" with ECM.




WIRING DIAGRAM




DIAGNOSTIC PROCEDURE

COMPONENT INSPECTION
1. Disconnect knock sensor harness connector.




2. Check continuity between terminal (a) and ground.

Resistance: 500 - 620 K Ohms at 25°C (77°F)

It is necessary to use an ohmmeter which can measure more than 10 M Ohms.

CAUTION:
- Do not use any knock sensors that have been dropped or physically damaged. Use only new ones.