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Inspection Procedure

HINT:

Read freeze frame data using Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air/fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.

  1. READ VALUE OF TECHSTREAM (MASS AIR FLOW RATE) 
    1. Connect Techstream to the DLC3.
    2. Put the engine in inspection mode (see SFI SYSTEM  ).
    3. Start the engine.
    4. Turn Techstream ON.
    5. Enter the following menus: Powertrain / Engine and ECT /Data List /All Data / MAF.
    6. Read its value using Techstream.

      Result 

      RESULT CHART

      Air Flow Rate (g/sec.) Proceed to
      0.0 A
      271.0 or more B
      Between 1.0 and 270.0 (*) C
      HINT:
      *: The value must be changed when the throttle valve is opened or closed.

    B:  Go to step  6

    C: CHECK FOR INTERMITTENT PROBLEMS 

    A: Go To Next Step 

  2. INSPECT MASS AIR FLOW METER (POWER SOURCE) 
    1. Turn the power switch ON (IG).
    2. Disconnect the M1 mass air flow meter connector.
    3. Measure the voltage between the terminal of the wire harness side connector and body ground.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      M1-1 (+B) - Body ground 9 to 14 V
    4. Reconnect the mass air flow meter connector.

    NG:  Go to step  5

    Fig 1: Identifying M1 Mass Air Flow Meter Connector Terminal
    G05673953Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go To Next Step 

  3. CHECK ECM (VG VOLTAGE) 
    1. Put the engine in inspection mode (see SFI SYSTEM  ).
    2. Start the engine.
    3. Measure the voltage between the specified terminals of the E5 ECM connector.

      HINT:

      The A/C switch should be turned OFF.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      E5-33 (VG) - E5-32 (EVG) Engine is idling 0.5 to 3.0 V

    OK: REPLACE ECM 

    Fig 2: Identifying E5 ECM Connector Terminal
    G05188636Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go To Next Step 

  4. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM) 
    1. Disconnect the M1 mass air flow meter connector.
      Fig 3: Identifying M1 Mass Air Flow Meter Connector Terminal
      G05673955Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the E5 ECM connector.
    3. Measure the resistance according to the value (s) in the table below.

      Standard resistance (Check for open) 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      M1-3 (VG) - E5-33 (VG) Below 1 Ω
      M1-2 (E2G) - E5-32 (EVG) Below 1 Ω

      Standard resistance (Check for short) 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      M1-3 (VG) or E5-33 (VG) - Body ground 10 kΩ or higher
      Fig 4: Identifying E5 ECM Connector Terminal
      G05188638Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Reconnect the mass air flow meter connector.
    5. Reconnect the ECM connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE MASS AIR FLOW METER 

  5. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - EFI M RELAY) 
    1. Remove the integration relay from the engine room relay block.
      Fig 5: Identifying Engine Room Relay Block
      G05188625Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the M1 mass air flow meter connector.
    3. Measure the resistance according to the value (s) in the table below.

      Standard resistance (Check for open) 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      M1-1 (+B) - 3I-8 (EFI M relay) Below 1 Ω

      Standard resistance (Check for short) 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      M1-1 (+B) or 3I-8 (EFI M relay) - Body ground 10 kΩ or higher
      Fig 6: Identifying M1 Mass Air Flow Meter Connector Terminal
      G05188640Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Reconnect the mass air flow meter connector.
    5. Reinstall the integration relay.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: CHECK ECM POWER SOURCE CIRCUIT 

  6. CHECK ECM (SENSOR GROUND) 
    1. Measure the resistance between the specified terminal of the E5 ECM connector and body ground.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      E5-32 (EVG) - Body ground Below 1 Ω

    NG: REPLACE ECM 

    Fig 7: Identifying E5 ECM Connector Terminal
    G05673959Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go To Next Step 

  7. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM) 
    1. Disconnect the M1 mass air flow meter connector.
      Fig 8: Identifying M1 Mass Air Flow Meter Connector Terminal
      G05188642Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the E5 ECM connector.
    3. Measure the resistance according to the value (s) in the table below.

      Standard resistance (Check for open) 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      M1-3 (VG) - E5-33 (VG) Below 1 Ω
      M1-2 (E2G) - E5-32 (EVG) Below 1 Ω

      Standard resistance (Check for short) 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      M1-3 (VG) or E5-33 (VG) - Body ground 10 kΩ or higher
      Fig 9: Identifying E5 ECM Connector Terminal
      G05188638Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Reconnect the mass air flow meter connector.
    5. Reconnect the ECM connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE MASS AIR FLOW METER