ECD SYSTEM, Diagnostic DTC:P0100

DTC Code DTC Name
P0100 Mass or Volume Air Flow Sensor "A" Circuit

DESCRIPTION

When the engine is running and the supply voltage to the ECM is outside the threshold, the ECM determines that the supply voltage to the mass air flow meter sub-assembly has decreased.

When the supply voltage to the mass air flow meter sub-assembly has decreased, this DTC differentiates when there is a malfunction with the mass air flow meter sub-assembly.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Memory

P0100

Mass or Volume Air Flow Sensor "A" Circuit

Either condition is met (3 trip detection logic):

  • Supply voltage to ECM while engine is running is less than 7 V for 1 second.

  • Supply voltage to ECM while engine is running is more than 17 V for 1 second.

  • Open or short in power source circuit

  • Battery

  • EFI MAIN NO. 1 relay

  • ECM

Does not come on

DTC stored

WIRING DIAGRAM

A372439E02

CAUTION / NOTICE / HINT

Note:

  • When replacing the ECM, the ECM needs registration and initialization.

    Click here

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

Tip:

  • When the ECM must be replaced, before replacing the ECM, perform the "Learning Values Save" function using the GTS. Then after installing the new ECM, perform all of the initialization/registrations for the "Learning Values Write" function by following the instructions shown on the GTS display.

  • 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 BATTERY VOLTAGE

    1. Check battery voltage.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    RECHARGE OR REPLACE BATTERYClick here

    OK

  2. CHECK HARNESS AND CONNECTOR

    1. Disconnect the negative (-) battery terminal.

    2. Disconnect the positive (+) battery terminal.

    3. Disconnect the ECM connector.

    4. Remove the EFI MAIN NO. 1 relay from the engine room and junction block.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      A62-4 (E1) - Body ground

      Always

      Below 1 Ω

      A62-5 (E2) - Body ground

      Always

      Below 1 Ω

      A62-17 (E3) - Body ground

      Always

      Below 1 Ω

      A62-18 (E4) - Body ground

      Always

      Below 1 Ω

      A62-15 (BATT) - positive (+) battery terminal

      Always

      Below 1 Ω

      A62-2 (+B) - 3 (EFI MAIN NO. 1 relay holder)

      Always

      Below 1 Ω

      A62-14 (+B2) - 3 (EFI MAIN NO. 1 relay holder)

      Always

      Below 1 Ω

      A62-1 (+B3) - 3 (EFI MAIN NO. 1 relay holder)

      Always

      Below 1 Ω

      A62-9 (MREL) - 1 (EFI MAIN NO. 1 relay holder)

      Always

      Below 1 Ω

      5 (EFI MAIN NO. 1 relay holder) - positive (+) battery terminal

      Always

      Below 1 Ω

      2 (EFI MAIN NO. 1 relay holder) - Body ground

      Always

      Below 1 Ω

      A62-15 (BATT) or positive (+) battery terminal - Body ground

      Always

      10 kΩ or higher

      A62-2 (+B) or 3 (EFI MAIN NO. 1 relay holder) - Body ground

      Always

      10 kΩ or higher

      A62-14 (+B2) or 3 (EFI MAIN NO. 1 relay holder) - Body ground

      Always

      10 kΩ or higher

      A62-1 (+B3) or 3 (EFI MAIN NO. 1 relay holder) - Body ground

      Always

      10 kΩ or higher

      A62-9 (MREL) or 1 (EFI MAIN NO. 1 relay holder) - Body ground

      Always

      10 kΩ or higher

      5 (EFI MAIN NO. 1 relay holder) or positive (+) battery terminal - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTORClick here

    OK

  3. INSPECT EFI MAIN NO. 1 RELAY

    1. Inspect the EFI MAIN NO. 1 relay.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE EFI MAIN NO. 1 RELAYClick here

    OK

  4. REPLACE ECM

    1. Replace the ECM.

      Click here

    Result

    Proceed to

    NEXT
    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIREDClick here

  5. REPLACE EFI MAIN NO. 1 RELAY

    1. Replace the EFI MAIN NO. 1 relay.

    Result

    Proceed to

    NEXT
    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIREDClick here

  6. REPAIR OR REPLACE HARNESS OR CONNECTOR

    1. Repair or replace the harness or connector.

    Result

    Proceed to

    NEXT
    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIREDClick here

  7. RECHARGE OR REPLACE BATTERY

    1. Recharge or replace the battery.

    Result

    Proceed to

    NEXT
    NEXT

  8. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON and turn the GTS on.

    3. Clear the DTCs.

      Powertrain > Engine and ECT > Clear DTCs

    4. Turn the ignition switch off and wait for 60 seconds or more [A].

    5. Perform road test [B].

    6. Repeat [A] and [B] for the number of trips detected.

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

      Powertrain > Engine and ECT > Trouble Codes

    8. Confirm that the DTC is not output again.

    Result

    Proceed to

    NEXT
    NEXT

    END