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Inspection Procedure

  1. PERFORM ACTIVE TEST BY TECHSTREAM (VACUUM SWITCHING VALVE) 
    1. Disconnect the vacuum hose from port F on the vacuum switching valve (for ACIS).
    2. Connect the Techstream to the DLC3.
    3. Start the engine.
    4. Enter the following menus:/Engine and ECT/Active Test/Active the VSV for Intake Control. Operate the ACIS VSV.
    5. Check the VSV air flow when switching the VSV.
      Fig 1: Performing Active Test By Techstream (Vacuum Switching Valve)
      G04968201Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK 

      TESTER CONDITION AND SPECIFIED CONDITION

      Tester Condition Specified Condition
      VSV is ON Air from port E flows out through port F
      VSV is OFF Air from port E flows out through the air filter

    NG: Go to step  4

    OK: Go to Next Step 

  2. CHECK VACUUM HOSES (INTAKE MANIFOLD - VACUUM SWITCHING VALVE, VACUUM SWITCHING VALVE - INTAKE AIR CONTROL VALVE) 
    1. Check the condition of the vacuum hoses between the intake manifold, vacuum switching valve (for ACIS) and IACV.
      1. The vacuum hoses are connected securely.
      2. The vacuum hoses are not cracked or damaged

        OK: The vacuum hoses are connected securely and not cracked or damaged. 

    NG: REPAIR OR REPLACE VACUUM HOSES 

    OK: Go to Next Step 

  3. INSPECT INTAKE AIR CONTROL VALVE 
    1. Inspect the intake air control valve (See INSPECTION ).

    NG: REPLACE INTAKE AIR CONTROL VALVE 

    OK: REPLACE ECM 

  4. INSPECT VACUUM SWITCHING VALVE (OPERATION) 
    1. Check that air flows from port E to the air filter.
    2. Apply positive (+) battery voltage across the terminals.
    3. Check that air flows from port E to port F.

    NG: REPLACE VACUUM SWITCHING VALVE 

    Fig 2: Inspecting Vacuum Switching Valve (Operation)
    G04968202Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  5. CHECK HARNESS AND CONNECTOR (VACUUM SWITCHING VALVE - ECM, VACUUM SWITCHING VALVE - EFI NO. 2 FUSE) 
    1. Check the wire harness between the VSV for ACIS and connector the ECM connector.
      1. Disconnect the V9 VSV for ACIS connector.
      2. Disconnect the E5 and E7 ECM connectors.
      3. Measure the resistance between the wire harness side connectors.

        Standard resistance (Check for open) 

        STANDARD RESISTANCE

        Tester Connection Specified Condition
        VSV for ACIS (V9-2) - ACIS (E5-33) Below 1 Ω

        Standard resistance (Check for short) 

        STANDARD RESISTANCE

        Tester Connection Specified Condition
        VSV for ACIS (V9-2) or ACIS (E5-33) - E1 (E7-1) 10 kΩ or higher
    2. Check the wire harness between the VSV for ACIS connector and the EFI relay.
      1. Disconnect the V9 VSV for ACIS connector.
      2. Remove the EFI relay from the engine room R/B
      3. Measure the resistance between the wire harness side connectors.
        Fig 3: Checking Harness And Connector (Vacuum Switching Valve - ECM, Vacuum Switching Valve - EFI No. 2 Fuse)
        G05264302Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard resistance (Check for open) 

        STANDARD RESISTANCE

        Tester Connection Specified Condition
        VSV for ACIS (V9-1) - EFI relay terminal 3 of R/B Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE ECM