ECD SYSTEM, Diagnostic DTC:P0101

DTC Code DTC Name
P0101 Mass Air Flow Circuit Range / Performance Problem

DESCRIPTION

Refer to DTC P0102 Click here.

P0101
DTC Detection Drive Pattern DTC Detection Condition Trouble Area
After warming up the engine coolant to 70°C (158°F), idle the engine for 10 seconds or more, and then maintain an engine speed of 2000 rpm or higher for 10 seconds or more.

Air flow rate from mass air flow meter sub-assembly is out of specified threshold under the following conditions (2 trip detection logic):


  • Engine speed is idling or more than 2000 rpm

  • Engine coolant temperature is 70°C (158°F) or higher

  • Mass air flow meter sub-assembly

  • Open or short in mass air flow meter subassembly circuit

  • Power source for mass air flow meter (voltage converter system)

  • Air filter

  • Intake system (leaks or blockages)

  • ECM

INSPECTION PROCEDURE

Tech Tips

Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was moving or stationary, whether the engine was warmed up or not, as well as other data recorded at the time of a malfunction.

PROCEDURE


  1. CHECK OTHER DTC OUTPUT (IN ADDITION TO DTC P0101)


    1. Replace the normal DLC3 cable (12 V specification) for the intelligent tester with the 24 V DLC3 cable.

      Note

      Be sure to use the 24 V DLC3 cable when connecting the intelligent tester to the DLC3. Using the normal DLC3 cable (12 V specification) will cause damage to the tester.

    2. Connect the intelligent tester to the DLC3.

    3. Turn the ignition switch to ON.

    4. Turn the tester on.

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

    6. Read the DTCs.

      Result
      Result Proceed to
      DTC P0101 is output A
      DTC P0101 and other DTCs are output B

    B

    GO TO DTC CHART Click here

    A

  2. CHECK AIR FILTER


    1. Visually check that the air filter is not excessively contaminated with dirt or oil.


    NG

    CLEAN OR REPLACE AIR FILTER

    OK

  3. INSPECT INTAKE SYSTEM


    1. Inspect the intake system Click here.


    NG

    REPAIR OR REPLACE INTAKE SYSTEM

    OK

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


    1. Disconnect the mass air flow meter sub-assembly 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 Condition Specified Condition
      I23-5 (FC) - E35-17 (VG) Always Below 1 Ω
      I23-4 (E2G) - E35-18 (EVG) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      I23-5 (FC) or E35-17 (VG) - Body ground Always 10 kΩ or higher

    4. Reconnect the mass air flow meter sub-assembly connector.

    5. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK MASS AIR FLOW METER SUB-ASSEMBLY (POWER SOURCE)


    1. A01CH9DE85
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Mass Air Flow Meter Sub-assembly)

      Disconnect the mass air flow meter sub-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 Switch Condition Specified Condition
      I23-3 (+B) - Body ground Ignition switch ON 11 to 14 V

    4. Reconnect the mass air flow meter sub-assembly connector.


    NG

    CHECK VOLTAGE CONVERTER SYSTEM Click here

    OK

  6. REPLACE MASS AIR FLOW METER SUB-ASSEMBLY


    1. Replace the mass air flow meter sub-assembly Click here.


    NEXT

  7. CHECK WHETHER DTC OUTPUT RECURS


    1. Replace the normal DLC3 cable (12 V specification) for the intelligent tester with the 24 V DLC3 cable.

      Note

      Be sure to use the 24 V DLC3 cable when connecting the intelligent tester to the DLC3. Using the normal DLC3 cable (12 V specification) will cause damage to the tester.

    2. Connect the intelligent tester to the DLC3.

    3. Clear the DTCs Click here.

    4. Turn the ignition switch off for 30 seconds or more.

    5. Start the engine

    6. Warm up the engine coolant temperature to 70°C (158°F).

    7. Maintain engine idle for 10 seconds or more.

    8. Maintain an engine speed of 2000 rpm or higher for 10 seconds or more.

    9. Turn the tester on.

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

    11. Read the DTCs using the intelligent tester.

      Result
      Display (DTC output) Proceed to
      DTC is not output A
      DTC P0101 is output B

    B

    REPLACE ECM

    A

    END