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Inspection Procedure

  1. PERFORM ACTIVE TEST BY INTELLIGENT TESTER (VSV FOR ACIS) 
    1. Disconnect the vacuum hose from the port F on the VSV for ACIS.
      Fig 1: Checking Vacuum Switching Valve Air Flow
      G05291559Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Connect the intelligent tester to the CAN VIM. Then connect the CAN VIM to the DLC3.
    3. Start the engine.
    4. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / INTAKE CTL VSV1. Operate the VSV (for ACIS).
    5. Check the VSV's air flow when switching the VSV.

      OK 

      TESTER CONDITION SPECIFIED CONDITION REFERENCE CHART

      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 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, VSV for ACIS and IACV.
      1. The vacuum hoses are connected securely.
      2. Vacuum hoses are not cranked 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 INTAKE AIR CONTROL VALVE ACTUATOR ).

    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.
      Fig 2: Checking Vacuum Switching Valve (Operation)
      G05291560Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Apply positive (+) battery voltage across the terminals.
    3. Check that air flows from port E to port F.

    NG: REPLACE VACUUM SWITCHING VALVE 

    OK: Go to next step 

  5. CHECK WIRE HARNESS (VACUUM SWITCHING VALVE - ECM, VACUUM SWITCHING VALVE - BODY GROUND) 
    1. Disconnect the V2 VSV for ACIS connector.
    2. Disconnect the E4 ECM connector.
      Fig 3: Disconnecting E4 ECM Connector Terminals
      G05291561Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      V2-2 - E4-3 (ACIS) Below 1 Ω
      V2-2 or E4-3 (ACIS) - Body ground 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  6. INSPECT EFI RELAY (Marking: EFI) 
    Fig 4: Inspecting EFI Relay
    G05291562Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the EFI relay from the engine room No. 2 relay block.
    2. Measure the resistance of the EFI relay.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      3 - 5 10 kΩ or higher
      3 - 5 Below 1 Ω (when battery voltage is applied to terminals 1 and 2)

    NG: REPLACE EFI RELAY 

    OK: REPLACE ECM