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DTC P2012: TGV Control Circuit Low Bank 2: Notes

DTC detecting condition: 

Immediately at fault recognition

Wiring diagram: 

Engine Electrical System Ref. to WIRING SYSTEM>ENGINE ELECTRICAL SYSTEM .

G16446398Courtesy of SUBARU OF AMERICA, INC.
CAUTION: Use the check board when measuring the ECM terminal voltage and resistance. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>GENERAL DESCRIPTION>PREPARATION TOOL>HOW TO USE CHECK BOARD .
NOTE: After the faulty parts are repaired or replaced, perform the final check in Basic Diagnostic Procedure. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>BASIC DIAGNOSTIC PROCEDURE>PROCEDURE .
  1. CHECK HARNESS BETWEEN ECM AND TUMBLE GENERATOR VALVE ACTUATOR LH CONNECTOR (SHORT TO POWER SUPPLY)  .
    1. Turn the ignition switch to OFF.
    2. Disconnect the connector from ECM.
    3. Turn the ignition switch to ON.
    4. Measure the voltage between ECM connector and engine ground.

      Connector & terminal 

      (E158) No. 45 (+) - Engine ground (-):

      (E158) No. 46 (+) - Engine ground (-):

    Is the voltage 5 V or more?

    Yes:  Repair the short circuit to power in harness between ECM connector and tumble generator valve actuator LH connector.

    No:  Replace the tumble generator valve actuator LH. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DOTC)>TUMBLE GENERATOR VALVE ACTUATOR .

    NOTE: The tumble generator valve actuator cannot be disassembled.