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Home >> Subaru >> 2021 >> WRX STI >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Diagnostics) (2.5L) (2 Of 4) >> Diagnostic Procedure with Diagnostic Trouble Code (DTC) >> DTC P0328: Knock/Combustion Vibration Sensor 1 Circuit High Bank 1 Or Single Sensor >> Notes
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DTC P0328: Knock/Combustion Vibration Sensor 1 Circuit High Bank 1 Or Single Sensor: Notes

DTC detecting condition: 

Immediately at fault recognition

Trouble symptom: 

CAUTION: After servicing or replacing faulty parts, perform Clear Memory Mode Refer to ENGINE (DIAGNOSTICS) (STI)>CLEAR MEMORY MODE>OPERATION ., and inspection mode Refer to ENGINE (DIAGNOSTICS) (STI)>INSPECTION MODE>PROCEDURE .

Wiring diagram: 

Engine Electrical System Refer to WIRING SYSTEM>ENGINE ELECTRICAL SYSTEM>WIRING DIAGRAM .

G12456792Courtesy of SUBARU OF AMERICA, INC.
  1. CHECK HARNESS BETWEEN ECM AND KNOCK SENSOR CONNECTOR. 
    1. Turn the ignition switch to OFF.
    2. Disconnect the connector from ECM.
    3. Measure the resistance between ECM connectors.

    Connector & terminal 

    (B137) No. 2 - (B134) No. 29:

    Is the resistance 600 kΩ or more?

    Yes:  Go to  2.

    No:  Repair the poor contact of ECM connector.

  2. CHECK KNOCK SENSOR. 
    1. Disconnect the connector from the knock sensor.
    2. Measure the resistance between knock sensor terminals.

    Terminals 

    No. 1 - No. 2:

    Is the resistance 600 kΩ or more?

    Yes:  Replace the knock sensor. Refer to FUEL INJECTION (FUEL SYSTEMS) (STI)>KNOCK SENSOR .

    No:  Repair the harness and connector.

    NOTE: In this case, repair the following item:
    • Open circuit in harness between ECM connector and knock sensor connector
    • Poor contact of knock sensor connector
    • Poor contact of coupling connector