СИСТЕМА SFI, Diagnostic DTC:P0100, P0102, P0103

DTC Code DTC Name
P0100 Mass or Volume Air Flow Circuit
P0102 Mass or Volume Air Flow Circuit Low Input
P0103 Mass or Volume Air Flow Circuit High Input

DESCRIPTION

The Mass Air Flow (MAF) meter is a sensor that measures the amount of air flowing through the throttle valve.

The ECM uses this information to determine the fuel injection time and to provide the appropriate air-fuel ratio.

Inside the MAF meter, there is a heated platinum wire which is exposed to the flow of intake air.

By applying a specific electrical current to the wire, the ECM heats it to a given temperature. The flow of incoming air cools both the wire and an internal thermistor, affecting their resistance. To maintain a constant current value, the ECM varies the voltage applied to the wire and internal thermistor. The voltage level is proportional to the airflow through the sensor, and the ECM uses it to calculate the intake air volume.

The circuit is constructed so that the platinum hot wire and temperature sensor create a bridge circuit, and the power transistor is controlled so that the potentials of A and B remain equal to maintain the predetermined temperature.

Tech Tips

When any of these DTCs are stored, the ECM enters fail-safe mode. During fail-safe mode, the ignition timing is calculated by the ECM, according to the engine speed and throttle valve position. Fail-safe mode continues until a pass condition is detected.

A005VQQE01
DTC No. DTC Detection Condition Trouble Area
P0100 The MAF meter voltage is below 0.2 V or higher than 4.9 V for 3 seconds (1 trip detection logic).

  • Open or short in MAF meter circuit

  • MAF meter

  • ECM
P0102 The MAF meter voltage is below 0.2 V for 3 seconds (1 trip detection logic).

  • Open or short in MAF meter circuit

  • MAF meter

  • ECM
P0103 The MAF meter voltage is higher than 4.9 V for 3 seconds (1 trip detection logic).

  • Open or short in MAF meter circuit

  • MAF meter

  • ECM

Tech Tips

When any of these DTCs are output, check the air-flow rate using the intelligent tester. Enter the following menus: Powertrain / Engine and ECT / Data List / MAF.

Mass Air Flow Rate (gm/s) Malfunction
Approximately 0.0

  • Open or short in Mass Air Flow (MAF) meter power source circuit

  • Open or short in VG circuit
271.0 or higher

  • Open in E2G circuit

WIRING DIAGRAM

A005W6IE05

INSPECTION PROCEDURE

Note

Inspect the fuses for circuits related to this system before performing the following inspection procedure.

Tech Tips

Read freeze frame data using the intelligent tester. 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, and other data from the time the malfunction occurred.

PROCEDURE

  1. CHECK DTC OUTPUT

    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG) and turn the tester on.

    3. Enter the following menus: Powertrain / Engine and ECT / DTC.

    4. Read the DTCs.

      Result
      Result Proceed to
      DTC P0100 and P0102 are output A
      DTC P0100 and P0103 are output B
    B

    CHECK HARNESS AND CONNECTOR (SENSOR GROUND) Click here

    A

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

    A005SQPE44

    1. Disconnect the B2 Mass Air Flow (MAF) meter connector.

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      B2-3 (+B) - Body ground Engine switch on (IG) 11 to 14 V
      Text in Illustration
      *1

      Front view of wire harness connector

      (to MAF Meter)

    3. Reconnect the MAF meter connector.

    NG

    CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - INTEGRATION RELAY) Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM)

    A005RGGE01

    1. Disconnect the B2 MAF meter connector.

    2. Disconnect the B39 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
      B2-5 (VG) - B39-118 (VG) Always Below 1 Ω
      B2-4 (E2G) - B39-116 (E2G)
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      B2-5 (VG) or B39-118 (VG) - Body ground Always 10 kΩ or higher
      Text in Illustration
      *1

      Front view of wire harness connector

      (to MAF Meter)
      *2

      Front view of wire harness connector

      (to ECM)

    4. Reconnect the MAF meter connector.

    5. Reconnect the ECM connector.

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. INSPECT MASS AIR FLOW METER

    1. Inspect the MAF meter Click here.

    NG

    REPLACE MASS AIR FLOW METER Click here

    OK

    REPLACE ECM Click here

  5. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - INTEGRATION RELAY)

    A005UDGE01

    1. Disconnect the B2 MAF meter connector.

    2. Remove the integration 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 Condition Specified Condition
      B2-3 (+B) - 1B-4 Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      B2-3 (+B) or 1B-4 - Body ground Always 10 kΩ or higher
      Text in Illustration
      *1

      Front view of wire harness connector

      (to MAF Meter)
      *2

      Front view of wire harness connector

      (to Integration Relay)
      *3 Engine Room No. 1 Relay Block

    4. Reconnect the MAF meter connector.

    5. Reinstall the integration relay.

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    CHECK ECM POWER SOURCE CIRCUIT Click here

  6. CHECK HARNESS AND CONNECTOR (SENSOR GROUND)

    1. Disconnect the B2 MAF meter connector.

      A005SQPE45

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      B2-4 (E2G) - Body ground Always Below 1 Ω
      Text in Illustration
      *1

      Front view of wire harness connector

      (to MAF Meter)

    3. Reconnect the MAF meter connector.

    NG

    CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM) Click here

    OK

    REPLACE MASS AIR FLOW METER Click here

  7. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM)

    A005RGGE01

    1. Disconnect the B2 MAF meter connector.

    2. Disconnect the B39 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
      B2-5 (VG) - B39-118 (VG) Always Below 1 Ω
      B2-4 (E2G) - B39-116 (E2G)
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      B2-5 (VG) or B39-118 (VG) - Body ground Always 10 kΩ or higher
      Text in Illustration
      *1

      Front view of wire harness connector

      (to MAF Meter)
      *2

      Front view of wire harness connector

      (to ECM)

    4. Reconnect the MAF meter connector.

    5. Reconnect the ECM connector.

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE ECM Click here