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Home >> Lexus >> 2009 >> GS 350 RWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Diagnostic Codes (P0010 - P0351)) >> SFI System >> DTC P0100: Mass or Volume Air Flow Circuit; DTC P0102: Mass or Volume Air Flow Circuit Low Input; DTC P0103: Mass or Volume Air Flow Circuit High Input >> Procedure
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DTC P0100: Mass or Volume Air Flow Circuit; DTC P0102: Mass or Volume Air Flow Circuit Low Input; DTC P0103: Mass or Volume Air Flow Circuit High Input: Procedure

  1. READ VALUE USING TECHSTREAM (MAF) 
    1. Connect the Techstream to the DLC3.
    2. Start the engine.
    3. Turn the Techstream on.
    4. Select the following menu items: Powertrain / Engine and ECT / Data List / MAF.
    5. Read the values displayed on the Techstream.

      Result

      Mass 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 change when the throttle valve is open or closed.

    C → CHECK FOR INTERMITTENT PROBLEMS 

    B → See step   8 

    A: Go to next step 

  2. INSPECT MASS AIR FLOW METER (POWER SOURCE VOLTAGE) 
    1. Disconnect the E83 Mass Air Flow (MAF) meter connector.
      Fig 1: Identifying E83 Mass Air Flow (MAF) Meter Connector
      GTY105486Courtesy 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 Specified Condition
      E83-3 (+B) - Body ground 9 to 14 V
    4. Reconnect the MAF meter connector.

    NG → See step   6 

    OK: Go to next step 

  3. INSPECT ECM (VG VOLTAGE) 
    1. Start the engine.
      Fig 2: Identifying E6 ECM Connector
      GTY102910Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      HINT: 

      The transmission gear selector lever should be in the P or N position and the A/C switch should be turned OFF.

      Standard voltage

      Tester Connection Condition Specified Condition
      E6-27 (VG) - E6-26 (E2G) Engine idling 0.5 to 3.0 V

    OK → REPLACE ECM 

    NG: Go to next step 

  4. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM) 
    1. Disconnect the E83 MAF meter connector.
      Fig 3: Identifying E83 MAF Meter And E6 ECM Connectors
      GTY105487Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the E6 ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for open)

      Tester Connection Specified Condition
      E83-5 (VG) - E6-27 (VG) Below 1 Ω
      E83-4 (E2G) - E6-26 (E2G) Below 1 Ω

      Standard resistance (Check for short)

      Tester Connection Specified Condition
      E83-5 (VG) or E6-27 (VG) - Body ground 10 kΩ or higher
    4. Reconnect the MAF meter connector.
    5. Reconnect the ECM connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → REPLACE MASS AIR FLOW METER 

  5. INSPECT EFI NO. 2 FUSE See step   4 

    NG → CHECK FOR SHORT IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE 

    OK: Go to next step 

  6. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - EFI NO. 2 FUSE) 
    1. Disconnect the E83 MAF meter connector.
      Fig 4: Identifying E83 MAF Meter Connector
      GTY100533Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Remove the EFI No. 2 fuse from the No. 2 engine room relay block.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for open)

      Tester Connection Specified Condition
      E83-3 (+B) - EFI NO. 2 fuse (2) Below 1 Ω

      Standard resistance (Check for short)

      Tester Connection Specified Condition
      E83-3 (+B) or EFI NO. 2 fuse (2) - Body ground 10 kΩ or higher
    4. Reinstall the EFI No. 2 fuse.
    5. Reconnect the MAF meter connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  7. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY - EFI NO. 2 FUSE) See step   6 

    NG → REPLACE ENGINE ROOM NO. 2 RELAY BLOCK, JUNCTION BLOCK 

    OK → CHECK ECM POWER SOURCE CIRCUIT 

  8. INSPECT ECM (SENSOR GROUND) 
    1. Measure the resistance according to the value(s) in the table below.
      Fig 5: Identifying E6 ECM Connector
      GTY104025Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard resistance

      Tester Connection Specified Condition
      E6-26 (E2G) - Body ground Below 1 Ω

    NG → REPLACE ECM 

    OK: Go to next step 

  9. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM) 
    1. Disconnect the E83 MAF meter connector.
      Fig 6: Identifying E83 MAF Meter And E6 ECM Connectors
      GTY105487Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the E6 ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for open)

      Tester Connection Specified Condition
      E83-5 (VG) - E6-27 (VG) Below 1 Ω
      E83-4 (E2G) - E6-26 (E2G) Below 1 Ω

      Standard resistance (Check for short)

      Tester Connection Specified Condition
      E83-5 (VG) or E6-27 (VG) - Body ground 10 kΩ or higher
    4. Reconnect the MAF meter connector.
    5. Reconnect the ECM connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → REPLACE MASS AIR FLOW METER 

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