СИСТЕМА SFI, Diagnostic DTC:P2120, P2122, P2123, P2125, P2127, P2128, P2138

DTC Code DTC Name
P2120 Throttle / Pedal Position Sensor / Switch "D" Circuit
P2122 Throttle / Pedal Position Sensor / Switch "D" Circuit Low Input
P2123 Throttle / Pedal Position Sensor / Switch "D" Circuit High Input
P2125 Throttle / Pedal Position Sensor / Switch "E" Circuit
P2127 Throttle / Pedal Position Sensor / Switch "E" Circuit Low Input
P2128 Throttle / Pedal Position Sensor / Switch "E" Circuit High Input
P2138 Throttle / Pedal Position Sensor / Switch "D" / "E" Voltage Correlation

CAUTION / NOTICE / HINT

DESCRIPTION

The accelerator pedal position sensor is mounted on the accelerator pedal rod assembly and has 2 sensor circuits: VPA (main) and VPA2 (sub). This sensor is a non-contact type and uses Hall-effect elements in order to yield accurate signals even in extreme driving conditions, such as at high speeds as well as very low speeds. The voltage, which is applied to terminals VPA and VPA2 of the ECM, varies between 0.5 V and 4.75 V in depending on the position of the accelerator pedal (throttle valve). The signal from VPA indicates the actual accelerator pedal position (throttle valve opening angle) and is used for engine control. The signal from VPA2 conveys the status of the VPA circuit and is used to check the accelerator pedal position sensor itself.

The ECM monitors the actual accelerator pedal position (throttle valve opening angle) through the signals from VPA and VPA2 and controls the throttle actuator according to these signals.

Tech Tips

This ETCS (Electronic Throttle Control System) does not use a throttle cable.

A01BC2RE12
DTC No. DTC Detection Condition Trouble Area
P2120 VPA fluctuates rapidly beyond the upper and lower malfunction thresholds for 0.5 seconds or more (1 trip detection logic).

  • Accelerator pedal position sensor


  • ECM
P2122 VPA is 0.4 V or less for 0.5 seconds or more when the accelerator pedal is fully released (1 trip detection logic).

  • Accelerator pedal position sensor


  • Open in VCP1 circuit


  • Open or short to ground in VPA circuit


  • ECM
P2123 VPA is 4.8 V or higher for 2.0 seconds or more (1 trip detection logic).

  • Accelerator pedal position sensor


  • Open in EPA circuit


  • ECM
P2125 VPA2 fluctuates rapidly beyond the upper and lower malfunction thresholds for 0.5 seconds or more (1 trip detection logic).

  • Accelerator pedal position sensor


  • ECM
P2127 VPA2 is 1.2 V or less for 0.5 seconds or more when the accelerator pedal is fully released (1 trip detection logic).

  • Accelerator pedal position sensor


  • Open in VCP2 circuit


  • Open or short to ground in VPA2 circuit


  • ECM
P2128

Conditions (a) and (b) continue for 2.0 seconds or more (1 trip detection logic):

(a) VPA2 is 4.8 V or higher.

(b) VPA is between 0.4 V and 3.45 V.

  • Accelerator pedal position sensor


  • Open in EPA2 circuit


  • ECM
P2138

Condition (a) or (b) continues for 2.0 seconds or more (1 trip detection logic):

(a) Difference between VPA and VPA2 is 0.02 V or less.

(b) VPA is 0.4 V or less and VPA2 is 1.2 V or less.

  • Short between VPA and VPA2 circuits


  • Accelerator pedal position sensor


  • ECM

Tech Tips

When any of these DTCs is stored, check the accelerator pedal position sensor voltage by entering the following menus: Powertrain / Engine and ECT / Data List / All Data / Accel Sensor Out No. 1 and Accel Sensor Out No. 2.

Trouble Area

Accel Sensor Out No. 1

When Accelerator Pedal Released

Accel Sensor Out No. 2

When Accelerator Pedal Released

Accel Sensor Out No. 1

When Accelerator Pedal Depressed

Accel Sensor Out No. 2

When Accelerator Pedal Depressed
VCP circuit open 0 to 0.2 V 0 to 0.2 V 0 to 0.2 V 0 to 0.2 V
Open or short to ground in VPA circuit 0 to 0.2 V 1.2 to 2.0 V 0 to 0.2 V 3.4 to 4.75 V
Open or short to ground in VPA2 circuit 0.5 to 1.1 V 0 to 0.2 V 2.6 to 4.5 V 0 to 0.2 V
EPA circuit open 4.5 to 5.5 V 4.5 to 5.5 V 4.5 to 5.5 V 4.5 to 5.5 V
Normal condition 0.5 to 1.1 V 1.2 to 2.0 V 2.6 to 4.5 V 3.4 to 4.75 V

Tech Tips

Accelerator pedal positions are expressed as voltages.

MONITOR DESCRIPTION

When the output voltage of either VPA or VPA2 deviates from the standard range, or the difference between the output voltages of the 2 sensor circuits is less than the threshold, the ECM determines that there is a malfunction in the accelerator pedal position sensor. The ECM then illuminates the MIL and stores a DTC.

Example:

When the output voltage of VPA drops below 0.4 V for more than 0.5 seconds when the accelerator pedal is fully depressed, DTC P2122 is stored.

If the malfunction is not repaired successfully, a DTC is stored 2 seconds after the engine is next started.

MONITOR STRATEGY

Required Sensors/Components Accelerator pedal position sensor
Frequency of Operation Continuous

COMPONENT OPERATING RANGE

VPA voltage 0.4 to 4.8 V
VPA2 voltage 1.2 to 4.8 V
Difference between VPA and VPA2 voltages More than 0.02 V

CONFIRMATION DRIVING PATTERN

A01BEDUE01

  1. Connect the intelligent tester to the DLC3.

  2. Turn the ignition switch to ON and turn the intelligent tester on.

  3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC operation).

  4. Turn the ignition switch off and wait for at least 30 seconds.

  5. Turn the ignition switch to ON and turn the intelligent tester on [A].

  6. Fully depress and release the accelerator pedal [B].

  7. Check that 5 seconds or more have elapsed since the ignition switch was turned to ON.

  8. Enter the following menus: Powertrain / Engine and ECT / DTC [C].

  9. 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.

  10. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

  11. Input the DTC: P2120, P2122, P2123, P2125, P2127, P2128 or P2138.

  12. Check the DTC judgment result.

    Intelligent Tester 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
    N/A

    • Unable to perform DTC judgment

    • Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit

    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 or N/A, perform steps [B] through [C] again.

FAIL-SAFE

The accelerator pedal position sensor has 2 sensor circuits: Main and Sub. If either circuit malfunctions, the ECM limits the engine output.

The ECM continues operating in fail-safe mode until a pass condition is detected, and the ignition switch is then turned off.

If both circuits malfunction, the ECM regards the accelerator pedal as being released. As a result, the throttle valve is closed and the engine idles.

WIRING DIAGRAM

A01BHNOE07

INSPECTION PROCEDURE

Tech Tips


  • These DTCs relate to the accelerator pedal position sensor.

  • Read freeze frame data using the intelligent tester. 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, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

PROCEDURE


  1. READ VALUE USING INTELLIGENT TESTER (ACCELERATOR PEDAL POSITION SENSOR)

    A01BHDVE02
    Text in Illustration
    *a Depressed
    *b Released

    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the intelligent tester on.

    4. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Accel Sensor Out No. 1 and Accel Sensor Out No. 2.

    5. Read the value displayed on the intelligent tester.

      Standard Voltage
      Accelerator Pedal Operation Accel Sensor Out No. 1 Accel Sensor Out No. 2 Difference between Accel Sensor Out No. 1 and Accel Sensor Out No. 2
      Released 0.5 to 1.1 V 1.2 to 2.0 V More than 0.02 V
      Depressed 2.6 to 4.5 V 3.4 to 4.75 V

    OK

    CHECK WHETHER DTC OUTPUT RECURS (ACCELERATOR PEDAL POSITION SENSOR DTCS) Click here

    NG

    CHECK HARNESS AND CONNECTOR (ACCELERATOR PEDAL POSITION SENSOR - ECM) Click here

  2. CHECK HARNESS AND CONNECTOR (ACCELERATOR PEDAL POSITION SENSOR - ECM)


    1. Disconnect the accelerator pedal position sensor 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
      B1-6 (VPA) - B9-18 (VPA) Always Below 1 Ω
      B1-5 (EPA) - B9-20 (EPA) Always Below 1 Ω
      B1-4 (VCPA) - B9-26 (VCPA) Always Below 1 Ω
      B1-3 (VPA2) - B9-19 (VPA2) Always Below 1 Ω
      B1-2 (EPA2) - B9-21 (EPA2) Always Below 1 Ω
      B1-1 (VCP2) - B9-27 (VCP2) Always Below 1 Ω
      B1-6 (VPA) or B9-18 (VPA) - Body ground Always 10 kΩ or higher
      B1-5 (EPA) or B9-20 (EPA) - Body ground Always 10 kΩ or higher
      B1-4 (VCPA) or B9-26 (VCPA) - Body ground Always 10 kΩ or higher
      B1-3 (VPA2) or B9-19 (VPA2) - Body ground Always 10 kΩ or higher
      B1-2 (EPA2) or B9-21 (EPA2) - Body ground Always 10 kΩ or higher
      B1-1 (VCP2) or B9-27 (VCP2) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. INSPECT ECM (VCPA AND VCP2 VOLTAGE)

    A01BHKHE63
    Text in Illustration
    *a

    Front view of wire harness connector

    (to Accelerator Pedal Position Sensor)

    1. Disconnect the accelerator pedal position sensor 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
      B1-4 (VCPA) - B1-5 (EPA) Ignition switch ON 4.5 to 5.5 V
      B1-1 (VCP2) - B1-2 (EPA2) Ignition switch ON 4.5 to 5.5 V

    NG

    REPLACE ECM Click here

    OK

  4. REPLACE ACCELERATOR PEDAL ROD ASSEMBLY


    1. Replace the accelerator pedal rod assembly Click here.


    NEXT

  5. CHECK WHETHER DTC OUTPUT RECURS (ACCELERATOR PEDAL POSITION SENSOR DTCS)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the intelligent tester on.

    4. Clear the DTCs Click here.

    5. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

    6. Read the DTCs.

      Result
      Result Proceed to
      P2120, P2122, P2123, P2125, P2127, P2128 and/or P2138 is output A
      No DTC is output B

    B

    END

    A

    REPLACE ECM Click here