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Air Intake Control Circuit [03/2014 - ]: Procedure

  1. PERFORM ACTIVE TEST USING TECHSTREAM (ACTIVATE THE VSV FOR AICS) 
    1. Connect the Techstream to the DLC3.
      GTY357175Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine / Active Test / Activate the VSV for AICS.
    5. Check the operation of the VSV when the VSV is operated using the Techstream.

      Standard

      Techstream Operation Specified Condition
      ON Air from port E flows out through port F
      OFF Air from port E flows out through the air filter

    NG → See step   2 

    OK → See step   7 

  2. CHECK VACUUM SWITCHING VALVE (FOR AIR INTAKE CONTROL VALVE) 
    1. Check the vacuum switching valve for air intake control valve. Refer to ON-VEHICLE INSPECTION [03/2014 - ] .

    NG → REPLACE VACUUM SWITCHING VALVE (FOR AIR INTAKE CONTROL VALVE) 

    OK: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (VACUUM SWITCHING VALVE FOR AIR INTAKE CONTROL VALVE) 
    1. Disconnect the vacuum switching valve for air intake control valve connector.
      GTY358244Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Turn the engine switch on (IG).
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      A14-1 - Body ground Engine switch on (IG) 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Vacuum Switching Valve for Air Intake Control Valve)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (EFI NO. 2 FUSE - VACUUM SWITCHING VALVE) 

    OK: Go to next step 

  4. CHECK HARNESS AND CONNECTOR (VACUUM SWITCHING VALVE FOR AIR INTAKE CONTROL VALVE - ECM) 
    1. Disconnect the vacuum switching valve for air intake control valve connector.
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      A14-2 - D1-61 (AICV) Always Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      A14-2 or D1-61 (AICV) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (VACUUM SWITCHING VALVE FOR AIR INTAKE CONTROL VALVE - ECM) 

    OK: Go to next step 

  5. INSPECT AIR CLEANER CAP SUB-ASSEMBLY (VACUUM SURGE TANK) 
    1. Inspect the vacuum surge tank. Refer to ON-VEHICLE INSPECTION [03/2014 - ] .

    NG → REPAIR OR REPLACE AIR CLEANER CAP SUB-ASSEMBLY 

    OK → See step   6 

  6. REPLACE ECM. Refer to  REMOVAL [03/2014 - ] 
  7. PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [03/2014 - ]