ECD SYSTEM (w/o DPF), 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

DESCRIPTION

Tech Tips


  • This is the repair procedure for the accelerator pedal position sensor circuit.

  • This electrical throttle system does not use a throttle cable.

  • This accelerator pedal position sensor is a non-contact type.

The accelerator pedal position sensor is mounted on the accelerator pedal rod assembly and detects the opening angle of the accelerator pedal. Since this sensor is electronically controlled with Hall-effect elements, accurate control and reliability can be obtained. It has 2 sensors to detect the accelerator pedal position and a malfunction of the accelerator pedal position sensor.

In the accelerator pedal position sensor, the voltage applied to pedal terminals VPA and VPA2 of the ECM changes between 0 V and 5 V in proportion to the opening angle of the accelerator pedal. The VPA is a signal to indicate the actual accelerator pedal opening angle which is used for the engine control, and the VPA2 is a signal to indicate the information about the opening angle which is used for detecting malfunctions. The ECM judges the current opening angle of the accelerator pedal using signals from terminals VPA and VPA2, and the ECM controls the throttle motor based on these signals.

A01BC2RE07
DTC No.

DTC Detection Condition

(All of following are 1 trip detection logic)

 Trouble Area
P2120

Following condition (a) or (b) met for 0.5 seconds or more:

(a) VPA voltage 0.4 V or less when VPA2 output indicates accelerator pedal opened

(b) VPA 4.8 V or more

  • Accelerator pedal position sensor (accelerator pedal rod assembly)

  • Accelerator pedal rod (arm) deformed

  • ECM
P2122 VPA voltage 0.4 V or less for 0.5 seconds or more when VPA2 output indicates accelerator pedal opened

  • Accelerator pedal position sensor (accelerator pedal rod assembly)

  • Open in VCPA circuit

  • VPA circuit open or ground short

  • Accelerator pedal rod (arm) deformed

  • ECM
P2123 VPA voltage 4.8 V or more for 2.0 seconds or more

  • Accelerator pedal position sensor (accelerator pedal rod assembly)

  • Open in EPA circuit

  • Accelerator pedal rod (arm) deformed

  • ECM
P2125

Following condition (a) or (b) met for 0.5 seconds or more:

(a) VPA2 voltage 1.2 V or less when VPA output indicates accelerator pedal opened

(b) VPA2 voltage 4.8 V or more

  • Accelerator pedal position sensor (accelerator pedal rod assembly)

  • Accelerator pedal rod (arm) deformed

  • ECM
P2127 VPA2 voltage 1.2 V or less for 0.5 seconds or more when VPA output indicates accelerator pedal opened

  • Accelerator pedal position sensor (accelerator pedal rod assembly)

  • Open in VCP2 circuit

  • VPA2 circuit open or ground short

  • Accelerator pedal rod (arm) deformed

  • ECM
P2128

Following conditions (a) and (b) met for 2.0 seconds or more:

(a) VPA2 voltage 4.8 V or more

(b) VPA voltage between 0.4 to 3.45 V

  • Accelerator pedal position sensor (accelerator pedal rod assembly)

  • Open in EPA2 circuit

  • Accelerator pedal rod (arm) deformed

  • ECM
P2138

Following condition (a) or (b) met for 2.0 seconds or more:

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

(b) VPA voltage 0.4 V or less and VPA2 voltage 1.2 V or less

  • Accelerator pedal position sensor (accelerator pedal rod assembly)

  • VPA and VPA2 circuits short circuited

  • Accelerator pedal rod (arm) deformed

  • ECM

Tech Tips

When DTC P2120, P2122, P2123, P2125, P2127, P2128, or P2138 is detected, check the output voltage of the accelerator pedal position sensor by selecting the following menu items on an intelligent tester : Powertrain / Engine / Data List / Accel Position 1 and Accel Position 2.

- Accelerator pedal released Accelerator pedal depressed
Trouble Area Accel Position 1 Accel Position 2 Accel Position 1 Accel Position 2
VCPA, VCP2 circuit open 0 to 0.2 V 0 to 0.2 V 0 to 0.2 V 0 to 0.2 V
VPA circuit open or ground short 0 to 0.2 V 1.2 to 2.0 V 0 to 0.2 V 3.4 to 5.0 V
VPA2 circuit open or ground short 0.5 to 1.1 V 0 to 0.2 V 2.6 to 4.5 V 0 to 0.2 V
EPA, EPA2 circuit open 4.5 to 5.0 V 4.5 to 5.0 V 4.5 to 5.0 V 4.5 to 5.0 V

WIRING DIAGRAM

A01BABXE01

INSPECTION PROCEDURE

Note

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

Tech Tips

Read freeze frame data using an intelligent tester. Freeze frame data record 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 (ACCEL POSITION 1 AND ACCEL POSITION 2)


    1. A01BDFBE07

      Connect an intelligent tester to the DLC3.

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

    3. Select the following menu items: Powertrain / Engine / Data List / Accel Position 1 and Accel Position 2.

    4. Read the values.

      Standard voltage
      Accelerator Pedal Operation Accel Position 1 Accel Position 2
      Released 0.5 to 1.1 V 1.2 to 2.0 V
      Depressed 2.6 to 4.5 V 3.4 to 5.0 V

    OK

    CHECK WHETHER DTC OUTPUT RECURS Click here

    NG

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


    1. A01BCMYE01

      Disconnect the B1 accelerator pedal position sensor connector.

    2. Disconnect the B9 ECM connector.

    3. Check the resistance.

      Standard resistance (Check for open)
      Tester Connection Specified Condition
      VCP2 (B1-1) - VCP2 (B9-27) Below 1 Ω
      EPA2 (B1-2) - EPA2 (B9-29) Below 1 Ω
      VPA2 (B1-3) - VPA2 (B9-23) Below 1 Ω
      VCPA (B1-4) - VCPA (B9-26) Below 1 Ω
      EPA (B1-5) - EPA (B9-28) Below 1 Ω
      VPA (B1-6) - VPA (B9-22) Below 1 Ω
      Standard resistance (Check for short)
      Tester Connection Specified Condition
      VCP2 (B1-1) or VCP2 (B9-27) - Body ground 10 kΩ or higher
      EPA2 (B1-2) or EPA2 (B9-29) - Body ground 10 kΩ or higher
      VPA2 (B1-3) or VPA2 (B9-23) - Body ground 10 kΩ or higher
      VCPA (B1-4) or VCPA (B9-26) - Body ground 10 kΩ or higher
      EPA (B1-5) or EPA (B9-28) - Body ground 10 kΩ or higher
      VPA (B1-6) or VPA (B9-22) - Body ground 10 kΩ or higher

    4. Reconnect the ECM connector.

    5. Reconnect the accelerator pedal position sensor connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. INSPECT ECM (VCPA AND VCP2 VOLTAGE)


    1. A01BGG8E11

      Disconnect the B1 accelerator pedal position sensor connector.

    2. Turn the ignition switch to ON.

    3. Measure the voltage between the terminals of the ECM connector.

      Standard voltage
      Tester Connection Specified Condition
      VCPA (B9-26) - EPA (B9-28) 4.5 to 5.5 V
      VCP2 (B9-27) - EPA2 (B9-29)

    4. Reconnect the accelerator pedal position sensor connector.


    NG

    REPLACE ECM

    OK

  4. REPLACE ACCELERATOR PEDAL ROD ASSEMBLY


    1. Replace accelerator pedal rod assembly Click here.


    NEXT

  5. CHECK WHETHER DTC OUTPUT RECURS


    1. Connect an intelligent tester to the DLC3.

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

    3. Select the following menu items: Powertrain / Engine / DTC / Clear.

    4. Clear DTCs.

    5. Start the engine.

    6. Allow the engine to idle for 15 seconds.

    7. Depress and release the accelerator pedal several times.

    8. Select the following menu items: Powertrain / Engine / DTC.

    9. Read DTCs.

      Result
      Display (DTC Output) Proceed To
      P2120, P2122, P2123, P2125, P2127, P2128, or P2138 output again A
      No output B

    B

    END

    A

    REPLACE ECM