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Inspection Procedure

  1. CHECK VACUUM HOSES 
    1. Check whether the cap of vacuum hose is missing or not.
    2. If the hose is damaged, replace the vacuum hose assembly.
    3. Check the air and vacuum hoses for looseness, disconnection and blockage.
      Fig 1: Checking Vacuum Hoses
      G03008331Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPAIR OR REPLACE VACUUM HOSES 
    2. OK: Go to next step. 
  2. CHECK VACUUM 
    1. Start the engine.
    2. Disconnect the vacuum hose from the vacuum tank.
    3. Check that an unconnected port located on the vacuum tank applies suction to your finger.
    4. Reconnect the vacuum hose.
      Fig 2: Checking Vacuum
      G03008332Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: CHECK AND REPLACE VACUUM SOURCE AND HOSES 
    2. OK: Go to next step. 
  3. INSPECT ECM 
    1. Connect the oscilloscope between terminals ACM and E1 of the E7 ECM connector.
    2. Warm up engine to normal operating temperature.
    3. Turn the A/C switch on.
    4. Measure the voltage between terminals ACM and E1 of the E7 ECM connector.

      Result: 

      ECM

      Condition Voltage
      Shift position is D range, and engine speed is 850 RPM or less. Pulse generation
      Shift position is D range, and engine speed is 950 RPM or more. 9 to 14 V
      Shift position is P range. 9 to 14 V
      Fig 3: Inspecting ECM
      G03008333Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Fig 4: Oscilloscope Waveform Signal Graph
      G03008334Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. OK: Go to step   6 
    2. NG: Go to next step. 
  4. INSPECT DUTY VACUUM SWITCHING VALVE (RESISTANCE) 
    1. Disconnect the V2 VSV for ACM connector.
    2. Measure the resistance between the terminals 1 and 2.

      Resistance: 19 to 21 a at 20°C (68°F) 

    3. Reconnect the VSV for ACM connector.
      Fig 5: Inspecting Duty Vacuum Switching Valve (Resistance)
      G03008335Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPLACE DUTY VACUUM SWITCHING VALVE 
    2. OK: Go to next step. 
  5. CHECK HARNESS AND CONNECTOR (VSV FOR ACM - ECM, VSV FOR ACM - EFI RELAY) 
    1. Check the wire harness between the VSV for ACM connector and the ECM connector.
      1. Disconnect the V2 VSV for ACM connector.
      2. Fig 6: Disconnecting V2 VSV For ACM Connector
        G03008336Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Disconnect the E7 ECM connector.
      4. Check the resistance between the wire harness side connectors.

        Standard (Check for open): 

        VSV FOR ACM - ECM (CHECK FOR OPEN)

        Tester Connection Specified Condition
        VSV for ACM (V2-2) - ACM (E7-33) Below 1 Ω

        Standard (Check for short): 

        VSV FOR ACM - ECM (CHECK FOR SHORT)

        Tester Connection Specified Condition
        VSV for ACM (V2-2) or ACM (E7-33) - Body ground 10 kΩ or higher
        Fig 7: Checking Harness And Connector (VSV For ACM - ECM, VSV For ACM - EFI Relay)
        G03008337Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      5. Reconnect the VSV for ACM connector.
      6. Reconnect the ECM connector.
    2. Check the wire harness between the VSV for ACM and the EFI relay.
      1. Inspect the EFI No. 2 fuse.
        • Remove the EFI No. 2 fuse from the fusible link block.
        • Check for continuity in the EFI No. 2 fuse.

        Standard: Continuity 

        • Reinstall the EFI No. 2 fuse.
      2. Fig 8: Inspecting EFI No. 2 Fuse
        G03008338Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Disconnect the V2 VSV for ACM connector.
      4. Remove the EFI relay from the engine room R/B.
      5. Check the resistance between the wire harness side connectors.

        Standard (Check for open): 

        VSV FOR ACM - EFI RELAY (CHECK FOR OPEN)

        Tester Connection Specified Condition
        VSV for ACM (V2-2) - EFI relay terminal 3 of R/B Below 1 Ω
      6. Reconnect the VSV for ACM connector.
      7. Reinstall the EFI relay.
    1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
    2. OK: REPLACE ECM (See  REPLACEMENT  ) 
  6. INSPECT DUTY VACUUM SWITCHING VALVE (OPERATION) 
    1. Remove the VSV for ACM.
    2. Check operation of the VSV for ACM when battery positive voltage is applied to the terminals of the VSV for ACM connector.

      Battery positive voltage is not applied: 

      The air from pipe G is flowing out through pipes E and H. 

      Battery positive voltage is applied: 

      The air from pipe F is flowing out through pipes E and H. 

    3. Reinstall the VSV for ACM.
      Fig 9: Inspecting Duty Vacuum Switching Valve (Operation)
      G03008339Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPLACE DUTY VACUUM SWITCHING VALVE 
    2. OK: Go to next step. 
  7. INSPECT FRONT ENGINE MOUNT INSULATOR 
    1. Disconnect the vacuum hose from the front engine mount insulator.
    2. Using MITYVAC (Hand-held Vacuum Pump), apply vacuum of 80 kPa (600 mmHg, 25 in.Hg) and wait for 1 minute.
    3. Check that there is no change in the needle movement of the MITYVAC.
    4. Check that there is no fluid leakage caused by a brake of a lower diaphragm.
    5. Reconnect the vacuum hose.
      Fig 10: Inspecting Front Engine Mount Insulator
      G03008340Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPLACE FRONT ENGINE MOUNT INSULATOR 
    2. OK: SYSTEM OK.