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Home >> Toyota >> 2009 >> RAV4 Base, 2.5 F, AWD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (2AR-FE) - Diagnostic Codes (1 Of 4) >> DTC P0102 Mass or Volume Air Flow Circuit Low Input; DTC P0103 Mass or Volume Air Flow Circuit High Input >> Inspection Procedure
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Inspection Procedure

NOTE: Inspect the fuses of circuits related to this system before performing the following inspection procedure.

HINT:

Read freeze frame data using the Techstream. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

  1. READ VALUE USING TECHSTREAM (MASS AIR FLOW RATE) 
    1. Connect the Techstream to the DLC3.
    2. Start the engine.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / MAF.
    5. Read the values displayed on the Techstream.

      Result 

      RESULT CHART

      Result Proceed to
      0.0 A
      271.0 or more B
      Between 1.0 and 270.0* C
      HINT:
      *: The value changes when the throttle valve is open or closed with the engine running.

      B: Go to step  6

      C: CHECK FOR INTERMITTENT PROBLEMS  (See CHECK FOR INTERMITTENT PROBLEMS )

      A: Go to next step 

  2. INSPECT MASS AIR FLOW METER (POWER SOURCE VOLTAGE) 
    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 SPECIFIED CONDITION CHART

      Tester Connection Switch Condition Specified Condition
      B1-3 (+B) - Body ground Ignition switch ON 11 to 14 V
    4. Reconnect the mass air flow meter connector.

      NG: Go to step  5

      Fig 1: Identifying Mass Air Flow Meter Connector Terminals
      G05996825Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: Go to next step 

  3. INSPECT MASS AIR FLOW METER 
    1. Inspect output voltage.
      1. Disconnect the mass air flow meter connector.
      2. Apply battery voltage across terminals +B and E2G.
      3. Connect the positive (+) tester probe to terminal VG, and the negative (-) tester probe to terminal E2G.
      4. Measure the voltage according to the value(s) in the table below.
        Fig 2: Identifying Mass Air Flow Meter Connector Terminals
        G05996826Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard Voltage 

        TESTER CONNECTION SPECIFIED CONDITION CHART

        Tester Connection Condition Specified Condition
        5 (VG) - 4 (E2G) Battery voltage applied across terminal +B and E2G 0.2 to 4.9 V
      5. Reconnect the mass air flow meter connector.

        NG: REPLACE MASS AIR FLOW METER  (See REMOVAL )

        OK: Go to next step 

  4. 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 SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      B1-5 (VG) - B30-94 (VG) Always Below 1 Ω
      B1-4 (E2G) - B30-117 (E2G)

      Standard Resistance (Check for short) 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      B1-5 (VG) or B30-94 (VG) - Body ground Always 10 kΩ or higher
    4. Reconnect the mass air flow meter connector.
    5. Reconnect the ECM connector.

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

      Fig 3: Identifying Mass Air Flow Meter Connector And ECM Connector
      G05996827Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: REPLACE ECM  (See REMOVAL )

  5. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - INTEGRATION RELAY) 
    1. Disconnect the mass air flow meter connector.
    2. Remove the integration relay (EFI MAIN relay) from the engine room No. 1 relay block.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for open) 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      B1-3 (+B) - 1A-4 Always Below 1 Ω

      Standard Resistance (Check for short) 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      B1-3 (+B) or 1A-4 - Body ground Always 10 kΩ or higher
    4. Reconnect the mass air flow meter connector.
    5. Reinstall the integration relay.

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

      Fig 4: Identifying Mass Air Flow Meter Connector And Integration Relay
      G05996828Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: GO TO ECM POWER SOURCE CIRCUIT (See )

  6. 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 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      B1-4 (E2G) - Body ground Always Below 1 Ω
    3. Reconnect the mass air flow meter connector.

      NG: Go to step 7 

      Fig 5: Identifying Mass Air Flow Meter Connector
      G05996829Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: REPLACE MASS AIR FLOW METER  (See REMOVAL )

  7. 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 SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      B1-5 (VG) - B30-94 (VG) Always Below 1 Ω
      B1-4 (E2G) - B30-117 (E2G)

      Standard Resistance (Check for short) 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      B1-5 (VG) or B30-94 (VG) - Body ground Always 10 kΩ or higher
    4. Reconnect the mass air flow meter connector.
    5. Reconnect the ECM connector.

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

      Fig 6: Identifying Mass Air Flow Meter Connector And ECM Connector
      G05996827Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: REPLACE ECM  (See REMOVAL )

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