ECD SYSTEM (w/o EGR Cooler Bypass Valve), Diagnostic DTC:P0100, P0102, P0103

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

DESCRIPTION

The mass air flow meter uses a platinum hot wire. The mass air flow meter consists of a platinum hot wire, a temperature sensor and a control circuit installed in a plastic housing. The mass air flow meter hot wire and temperature sensor (located in the intake air by-pass of the housing) detect changes in the intake air temperature.

The hot wire is maintained at the predetermined temperature by controlling the current flow through the hot wire. This current flow is then related as the output voltage of the mass air flow meter.

The circuit is constructed so that the platinum hot wire and temperature sensor provide a bridge circuit, with the power transistor controlled so that the potential of A and B remains equal to maintain the predetermined temperature.

A01KIMRE01
DTC No. DTC Detection Condition Trouble Area
P0100

Open or short in mass air flow meter circuit for more than 3 seconds with engine speed at 2,000 rpm or less

(1 trip detection logic)

  • Open or short in mass air flow meter circuit

  • Mass air flow meter

  • ECM
P0102

Open in mass air flow meter circuit for more than 3 seconds with engine speed at 2000 rpm or less

(1 trip detection logic)
P0103

Short in mass air flow meter circuit for more than 3 seconds with engine speed at 2,000 rpm or less

(1 trip detection logic)

Tech Tips

After confirming DTC P0100, P0102, or P0103, check the mass air flow ratio in the "Powertrain / Engine and ECT / Data List / MAF" menu using the intelligent tester.

Reference:
Air Flow Value (g/sec.) Malfunction
Approximately 0.0

  • Open in mass air flow meter power source circuit

  • Open or short in VG circuit
167.5 or more Open in EVG circuit

WIRING DIAGRAM

A01KH0NE01

INSPECTION PROCEDURE

Tech Tips

Read freeze frame data using the intelligent tester. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, freeze frame data can help determine if the vehicle was running or stopped, if the engine was warmed up or not, and other data from the time the malfunction occurred.

Note

If the ECM is replaced, the new ECM needs initialization Click here.

PROCEDURE


  1. READ VALUE USING INTELLIGENT TESTER (MASS AIR FLOW RATE)


    1. Connect an intelligent tester to the DLC3.

    2. Start the engine and turn the tester ON.

    3. Select the following menu items: Powertrain / Engine and ECT / Data List / MAF.

    4. Read the value displayed on the intelligent tester.

      Result
      Air Flow Rate (g/sec.) Proceed to
      0.0 A
      167.5 or more B

      Between 1 and 167.4*

      		C

      Tech Tips

      *: The value must change when the throttle valve is opened or closed.


    B

    CHECK ECM (SENSOR GROUND) Click here

    C

    CHECK FOR INTERMITTENT PROBLEMS

    A

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


    1. A01KG5VE18
      Text in Illustration
      *1 Mass Air Flow Meter Connector
      *a Wire Harness Side
      *b Front View

      Disconnect the A9 mass air flow meter connector.

    2. Turn the ignition switch ON.

    3. Measure the voltage of the terminal of the wire harness side connector and the body ground.

      Standard voltage
      Tester Connection Specified Condition
      A9-1 - Body ground 11 to 14 V

    4. Reconnect the mass air flow meter connector.


    NG

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

    OK

  3. INSPECT ECM (VG VOLTAGE)


    1. A01KF0AE98
      Text in Illustration
      *1 ECM Connector

      Start the engine.

    2. Measure the voltage of the ECM connector.

      Standard voltage
      Tester Connection Condition Specified Condition
      E5-24 (VG) - E5-32 (EVG) Engine idling 0.5 to 3.4 V

      Tech Tips

      The A/C switch should be turned OFF.


    OK

    REPLACE ECM

    NG

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


    1. A01KGHAE13
      Text in Illustration
      *1 Mass Air Flow Meter Connector
      *2 ECM Connector
      *a Wire Harness Side
      *b Front View

      Disconnect the A9 mass air flow meter connector.

    2. Disconnect the E5 ECM connector.

    3. Check the resistance.

      Standard resistance (Check for open)
      Tester Connection Specified Condition
      A9-3 - E5-24 (VG) Below 1 Ω
      A9-2 - E5-32 (EVG) Below 1 Ω
      Standard resistance (Check for short)
      Tester Connection Specified Condition
      A9-3 or E5-24 (VG) - Body ground 10 kΩ or higher
      A9-2 or E5-32 (EVG) - Body ground 10 kΩ or higher

    4. Reconnect the mass air flow meter connector.

    5. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE MASS AIR FLOW METER

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


    1. A01KEV9E02
      Text in Illustration
      *1 Mass Air Flow Meter Connector
      *2 Relay Block No. 2
      *3 EFI MAIN Relay
      *a Wire Harness Side
      *b Front View

      Disconnect the A9 mass air flow meter connector.

    2. Remove the EFI MAIN relay from the relay block No.2.

    3. Check the resistance.

      Standard resistance (Check for open)
      Tester Connection Specified Condition
      3 (EFI MAIN relay) - A9-1 Below 1 Ω
      Standard resistance (Check for short)
      Tester Connection Specified Condition
      3 (EFI MAIN relay) or A9-1 - Body ground 10 kΩ or higher

    4. Reinstall the FI MAIN relay.

    5. Reconnect the mass air flow meter connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    INSPECT ECM POWER SOURCE CIRCUIT

  6. CHECK ECM (SENSOR GROUND)


    1. A01KF0AE99
      Text in Illustration
      *1 ECM Connector

      Measure the resistance of the ECM connector.

      Standard resistance
      Tester Connection Specified Condition
      E5-32 (EVG) - Body ground Below 1 Ω

    NG

    REPLACE ECM

    OK

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


    1. A01KGHAE13
      Text in Illustration
      *1 Mass Air Flow Meter Connector
      *2 ECM Connector
      *a Wire Harness Side
      *b Front View

      Disconnect the A9 mass air flow meter connector.

    2. Disconnect the E5 ECM connector.

    3. Check the resistance.

      Standard resistance (Check for open)
      Tester Connection Specified Condition
      A9-3 - E5-24 (VG) Below 1 Ω
      A9-2 - E5-32 (EVG) Below 1 Ω
      Standard resistance (Check for short)
      Tester Connection Specified Condition
      A9-3 or E5-24 (VG) - Body ground 10 kΩ or higher
      A9-2 or E5-32 (EVG) - Body ground 10 kΩ or higher

    4. Reconnect the mass air flow meter connector.

    5. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE MASS AIR FLOW METER