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Home >> Scion >> 2016 >> FR-S Automatic Trans >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Diagnostic Codes (P000A-P0230)) >> SFI System >> DTC P0102: Mass Or Volume Air Flow Circuit Low Input; DTC P0103: Mass Or Volume Air Flow Circuit High Input [05/2014 - ] >> Procedure
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DTC P0102: Mass Or Volume Air Flow Circuit Low Input; DTC P0103: Mass Or Volume Air Flow Circuit High Input [05/2014 - ]: 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

    B → See step   5 

    A: Go to next step 

  2. CHECK TERMINAL VOLTAGE (POWER SOURCE OF MASS AIR FLOW METER) 
    GTY420713Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    TEXT IN ILLUSTRATION

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

      Standard Voltage

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

    NG → See step   7 

    OK: Go to next step 

  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 chart below.

      Standard Resistance (Check for open)

      Tester Connection Condition Specified Condition
      C33-22 (VG) - C16-5 (VG) Always Below 1 Ω
      C33-29 (E2G) - C16-4 (E2G) Always Below 1 Ω

      Standard Resistance (Check for short)

      Tester Connection Condition Specified Condition
      C33-22 (VG) or C16-5 (VG) - Body ground Always 10 kΩ or higher
      C33-29 (E2G) or C16-4 (E2G) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  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 [05/2014 - ] .
    2. Inspect the mass air flow meter, referring to the Inspection for Mass Air Flow Meter. Refer to INSPECTION [05/2014 - ] .
    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.

    NG → See step   9 

    OK → See step   10 

  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 chart below.

      Standard Resistance (Check for open)

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

    NG → See step   6 

    OK → See step   11 

  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 chart 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

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   10 

  7. CHECK RELAY (EFI MAIN1) 
    1. Inspect the EFI MAIN1 relay. Refer to ON-VEHICLE INSPECTION [05/2014 - ] - STEP 1 .

    NG → REPLACE RELAY (EFI MAIN1) 

    OK: Go to next step 

  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 chart 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

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   12 

  9. REPLACE MASS AIR FLOW METER. Refer to  REMOVAL [05/2014 - ] 
  10. REPLACE ECM. Refer to  REMOVAL [05/2014 - ] 
  11. REPLACE MASS AIR FLOW METER. Refer to  REMOVAL [05/2014 - ] 
  12. CHECK ECM POWER SOURCE CIRCUIT. Refer to  ECM POWER SOURCE CIRCUIT [05/2014 - ]