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DTC P0102: Mass or Volume Air Flow Circuit Low Input; DTC P0103: Mass or Volume Air Flow Circuit High Input [06/2016 - ]: Procedure

  1. READ DTC OUTPUT 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine / Trouble Codes.
    5. Read DTCs.
      RESULT

      Result Proceed to
      DTC P0102 is output A
      DTC P0103 is output B

    Result: 

    B 

    See step  5

    Result: 

    A 

    See step  2

  2. CHECK TERMINAL VOLTAGE (POWER SOURCE OF MASS AIR FLOW METER) 
    GTY719731Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the mass air flow meter connector.
    2. Turn the ignition switch to ON.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      C16-3 (+B) - Body ground Ignition switch ON 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Mass Air Flow Meter)

    Result: 

    NG 

    See step  7

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM) 
    1. Disconnect the mass air flow meter 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
      A33-22 (VG) - C16-5 (VG) Always Below 1 Ω
      A33-29 (E2G) - C16-4 (E2G) Always Below 1 Ω

      Standard Resistance (Check for short)

      Tester Connection Condition Specified Condition
      A33-22 (VG) or C16-5 (VG) - Body ground Always 10 kΩ or higher
      A33-29 (E2G) or C16-4 (E2G) - Body ground Always 10 kΩ or higher

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  4

  4. INSPECT MASS AIR FLOW METER 
    1. Inspect the mass air flow meter, referring to the On-vehicle Inspection for Mass Air Flow Meter (Refer to ON-VEHICLE INSPECTION [06/2016 - ] ).
    2. Inspect the mass air flow meter, referring to the Inspection for Mass Air Flow Meter (Refer to INSPECTION [06/2016 - ] ).
    3. Inspect the function of the mass air flow meter.
      1. Connect the Techstream to the DLC3.
      2. Turn the ignition switch to ON.
      3. Turn the Techstream on.
      4. Enter the following menus: Powertrain / Engine / Data List / MAF.
      5. Start the engine.
      6. Check that the MAF value changes when the engine is raced.

        OK

        The reading changes.

    Result: 

    OK 

    REPLACE ECM 

    (Refer to REMOVAL [06/2016 - ] )

    Result: 

    NG 

    REPLACE MASS AIR FLOW METER 

    (Refer to REMOVAL [06/2016 - ] )

  5. CHECK HARNESS AND CONNECTOR (SENSOR GROUND) 
    1. Disconnect the mass air flow meter connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for open)

      Tester Connection Condition Specified Condition
      C16-4 (E2G)- Body ground Always Below 1 Ω

    Result: 

    OK 

    REPLACE MASS AIR FLOW METER 

    (Refer to REMOVAL [06/2016 - ] )

    Result: 

    NG 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM) 
    1. Disconnect the mass air flow meter 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
      A33-29 (E2G) - C16-4 (E2G) Always Below 1 Ω

      Standard Resistance (Check for short)

      Tester Connection Condition Specified Condition
      A33-29 (E2G) or C16-4 (E2G) - Body-ground Always 10 kΩ or higher

    Result: 

    OK 

    REPLACE ECM 

    (Refer to REMOVAL [06/2016 - ] )

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  7. CHECK RELAY (EFI MAIN1) 
    1. Inspect the EFI MAIN1 relay (Refer to PROCEDURE - Step 1 ).

    Result: 

    NG 

    REPLACE RELAY (EFI MAIN1) 

    Result: 

    OK 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - EFI MAIN1 RELAY) 
    1. Disconnect the mass air flow meter connector.
    2. Remove the EFI MAIN1 relay from the engine room relay block assembly.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for open)

      Tester Connection Condition Specified Condition
      EFI MAIN1 relay terminal 3 - C16-3 (+B) Always Below 1 Ω

      Standard Resistance (Check for short)

      Tester Connection Condition Specified Condition
      EFI MAIN1 relay terminal 3 or C16-3 (+B) - Body ground Always 10 kΩ or higher

    Result: 

    OK 

    CHECK ECM POWER SOURCE CIRCUIT 

    (Refer to ECM Power Source Circuit [06/2016 - 03/2017] , or refer to ECM Power Source Circuit [03/2017 - ] )

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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