СИСТЕМА ECD, Diagnostic DTC:P0100

DTC Code DTC Name
P0100 Mass Air Flow Circuit Malfunction

DESCRIPTION

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

There is little variation in the output from the mass air flow meter assembly, as it is hardly affected by the resistance of the wire harness.

The internal circuit of the mass air flow meter assembly contains a hot wire and cold wire. A voltage is output through a bridge circuit (refer to the illustration) indicating the cooling of the hot wire according to the intake air amount. This voltage is then converted into a periodic signal by the periodic signal conversion circuit and output to the ECM. The frequency varies between approximately 1945 and 8500 Hz depending on the air flow rate. The ECM calculates the mass air flow rate based on this frequency.

A00Y73VE05
DTC No. Detection Item DTC Detection Condition Trouble Area MIL Memory
P0100 Mass Air Flow Circuit Malfunction Mass air flow meter assembly signal frequency is less than 850 Hz with the engine speed at 400 rpm or higher for 3 seconds (1 trip detection logic).

  • Open or short in mass air flow meter assembly circuit

  • Mass air flow meter assembly

  • ECM

 Comes on DTC stored
Related Data List
DTC No. Data List
P0100 MAF

Tech Tips


  • If DTC P0100 is stored, the following symptoms may appear (as the ECM mistakenly determines that there is less air than the actual intake air amount, EGR is decreased according to the target EGR):


    • Combustion noise increases

CONFIRMATION DRIVING PATTERN

DTC No. DTC Detection Drive Pattern
P0100 3 seconds after engine is started

WIRING DIAGRAM

A00YB4EE01

CAUTION / NOTICE / HINT

Note


  • Inspect the fuses of circuits related to this system before performing the following procedure.

  • After replacing the ECM, the new ECM needs registration (Click here) and initialization Click here.

Tech Tips

Read freeze frame data using the GTS. 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 TERMINAL VOLTAGE (POWER SOURCE OF MASS AIR FLOW METER ASSEMBLY)


    1. A00Y6F6C03
      *a

      Front view of wire harness connector

      (to Mass Air Flow Meter Assembly)

      Disconnect the mass air flow meter assembly 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 Condition Specified Condition
      B2-3 (+B) - Body ground Ignition switch ON 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    GO TO STEP 6 Click here

    OK

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


    1. Disconnect the mass air flow meter assembly connector.

    2. Disconnect the ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      B2-1 (VG) - B164-65 (VG) Always Below 1 Ω
      B2-2 (E2G) - B164-64 (EVG) Always Below 1 Ω
      B2-1 (VG) or B164-65 (VG) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR Click here

    OK

  3. REPLACE MASS AIR FLOW METER ASSEMBLY


    1. Replace the mass air flow meter assembly.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  4. CHECK WHETHER DTC OUTPUT RECURS


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Clear the DTCs.


      Powertrain > Engine and ECT > Clear DTCs

    5. After engine is started for 3 seconds.

    6. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

    7. Read the DTCs.


      Powertrain > Engine and ECT > Trouble Codes
      Result
      Result Proceed to
      DTC P0100 is output A
      DTC is not output B

    B

    END

    A

  5. REPLACE ECM


    1. Replace the ECM.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

    GO TO STEP 7 Click here

  6. REPAIR OR REPLACE HARNESS OR CONNECTOR

    Tech Tips

    If the voltage at the mass air flow meter assembly connector is not 11 to 14 V, repair or replace the harness and connector between the mass air flow meter assembly and EFI-MAIN relay (including the EFI NO. 1 fuse).


    1. Repair or replace the harness or connector.

      Result
      Proceed to
      NEXT

    NEXT

  7. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Clear the DTCs.


      Powertrain > Engine and ECT > Clear DTCs

    5. Start the engine and wait for 3 seconds or more.

    6. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

    7. Confirm that the DTC is not output.


      Powertrain > Engine and ECT > Trouble Codes
      Result
      Proceed to
      NEXT

    NEXT

    END