SFI SYSTEM(w/ Canister Pump Module), Diagnostic DTC:P010012, P010017

DTC Code DTC Name
P010012 Mass or Volume Air Flow Sensor "A" Circuit Short to Battery
P010017 Mass or Volume Air Flow Sensor "A" Circuit Voltage Above Threshold

DESCRIPTION

The mass air flow meter sub-assembly is a sensor that measures the amount of air flowing through the throttle valve. The ECM uses this information to determine fuel injection duration and to provide an appropriate air fuel ratio.

Inside the mass air flow meter sub-assembly, 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 specific 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 the 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, boost prohibited and 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, and the engine switch is then turned off.

B0076C0E15
*1 Temperature Sensor (Thermistor)
*2 Power Transistor
*3 Platinum Hot Wire (Heater)
*4 Output Voltage
DTC No. Detection Item DTC Detection Condition Trouble Area MIL Memory Note
P010012 Mass or Volume Air Flow Sensor "A" Circuit Short to Battery

The mass air flow meter sub-assembly voltage is higher than 4.9 V for 3 seconds or more.

(1 trip detection logic: Engine speed is less than 4000 rpm)

  • Open or short in mass air flow meter sub-assembly circuit

  • Mass air flow meter sub-assembly

  • ECM

 Comes on DTC stored SAE Code: P0103
P010017 Mass or Volume Air Flow Sensor "A" Circuit Voltage Above Threshold

The mass air flow meter sub-assembly voltage is higher than 4.9 V for 3 seconds or more.

(2 trip detection logic: Engine speed is 4000 rpm or higher)

  • Open or short in mass air flow meter sub-assembly circuit

  • Mass air flow meter sub-assembly

  • ECM

 Comes on DTC stored SAE Code: P0103

Tech Tips

When these DTCs are output, check the mass air flow rate in the Data List. Enter the following menus: Powertrain / Engine / Data List / Mass Air Flow Sensor.

DTC No. Mass Air Flow Sensor Malfunction

P010012

P010017

 271.0 gm/sec or more

  • Short in VG circuit to power source circuit

  • Open in E2G circuit

If the Data List values is normal it may be due to a temporary recovery from the malfunction condition. Check for intermittent problems.

Click here

MONITOR DESCRIPTION

If there is a defect or an open or short circuit in the mass air flow meter sub-assembly, the voltage level deviates from the normal operating range. The ECM interprets this deviation as a malfunction in the mass air flow meter sub-assembly circuit and stores a DTC.

Example:

When the sensor output voltage remains higher than 4.9 V for 3 seconds or more, the ECM stores a DTC.

MONITOR STRATEGY

Frequency of Operation Continuous

CONFIRMATION DRIVING PATTERN

B0077LFE21

  1. Connect the GTS to the DLC3.

  2. Turn the engine switch on (IG).

  3. Turn the GTS on.

  4. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).

  5. Turn the engine switch off and wait for at least 30 seconds.

  6. Turn the engine switch on (IG) [A].

  7. Turn the GTS on.

  8. Start the engine.

  9. Idle the engine for 5 seconds [B].

  10. Enter the following menus: Powertrain / Engine / Trouble Codes [C].

  11. Read the pending DTCs.

    Tech Tips


    • If a pending DTC is output, the system is malfunctioning.

    • If a pending DTC is not output, perform the following procedure.

  12. Run the engine at an engine speed of 4000 rpm or higher for 5 seconds [D].

  13. Enter the following menus: Powertrain / Engine / Trouble Codes [E].

  14. Read the pending DTCs.

    Tech Tips


    • If a pending DTC is output, the system is malfunctioning.

    • If a pending DTC is not output, perform the following procedure.

  15. Enter the following menus: Powertrain / Engine / Utility / All Readiness.

  16. Input the DTC: P010012 or P010017.

  17. Check the DTC judgment result.

    GTS Display Description
    NORMAL

    • DTC judgment completed

    • System normal
    ABNORMAL

    • DTC judgment completed

    • System abnormal
    INCOMPLETE

    • DTC judgment not completed

    • Perform driving pattern after confirming DTC enabling conditions

    Tech Tips


    • If the judgment result shows NORMAL, the system is normal.

    • If the judgment result shows ABNORMAL, the system has a malfunction.

    • If the judgment result shows INCOMPLETE, perform steps [B] through [E] again.

WIRING DIAGRAM

B0072VKE02

CAUTION / NOTICE / HINT

Note

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

Tech Tips

Read freeze frame data using the GTS. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.

PROCEDURE


  1. 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
      Tester Connection Condition Specified Condition
      F38-4 (E2G) - F87-115 (E2G) Always Below 1 Ω
      F38-5 (VG) or F87-116 (VG) - Other terminals Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. CHECK HARNESS AND CONNECTOR (SENSOR GROUND)


    1. Disconnect the mass air flow meter sub-assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F38-4 (E2G) - Body ground Always Below 1 Ω

      Tech Tips

      Perform "Inspection After Repair" after replacing the mass air flow meter sub-assembly.

      Click here

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE MASS AIR FLOW METER SUB-ASSEMBLY Click here

    NG

    REPLACE ECM Click here