ECD SYSTEM, Diagnostic DTC:P2120,P2122,P2123,P2125,P2127,P2128 and 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

Tip:

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

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

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

The accelerator pedal sensor assembly is mounted on the accelerator pedal 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. The accelerator pedal sensor assembly has 2 sensors to detect the accelerator position and a malfunction of the accelerator pedal sensor assembly.

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 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.

A255815E09

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Memory

P2120

Throttle / Pedal Position Sensor / Switch "D" Circuit

Condition (a) continues for 0.5 seconds (1 trip detection logic):

(a) VPA is below 0.4 V and VPA2 is more than 0.97 deg, or VPA is higher than 4.8 V.

  • Accelerator pedal sensor assembly

  • Accelerator pedal sensor assembly deformed

  • ECM

Comes on

DTC stored

P2122

Throttle / Pedal Position Sensor / Switch "D" Circuit Low Input

Conditions (a) and (b) continue for 0.5 seconds (1 trip detection logic):

(a) VPA is below 0.4 V.

(b) VPA2 is more than 2.7 deg.

  • Accelerator pedal sensor assembly

  • Open in VCPA circuit

  • VPA circuit open or ground short

  • Accelerator pedal sensor assembly deformed

  • ECM

Comes on

DTC stored

P2123

Throttle / Pedal Position Sensor / Switch "D" Circuit High Input

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

(a) VPA is higher than 4.8 V.

  • Accelerator pedal sensor assembly

  • Open in EPA circuit

  • Accelerator pedal sensor assembly deformed

  • ECM

Comes on

DTC stored

P2125

Throttle / Pedal Position Sensor / Switch "E" Circuit

Condition (a) continues for 0.5 seconds (1 trip detection logic):

(a) VPA2 is below 1.2 V and VPA is more than 2.7 deg, or VPA2 is higher than 4.8 V and VPA is higher than 0.4 V but below 3.45 V.

  • Accelerator pedal sensor assembly

  • Accelerator pedal sensor assembly deformed

  • ECM

Comes on

DTC stored

P2127

Throttle / Pedal Position Sensor / Switch "E" Circuit Low Input

Conditions (a) and (b) continue for 0.5 seconds (1 trip detection logic):

(a) VPA2 is below 1.2 V

(b) VPA1 is more than 2.7 deg.

  • Accelerator pedal sensor assembly

  • Open in VCP2 circuit

  • VPA2 circuit open or ground short

  • Accelerator pedal sensor assembly deformed

  • ECM

Comes on

DTC stored

P2128

Throttle / Pedal Position Sensor / Switch "E" Circuit High Input

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

(a) VPA2 is higher than 4.8 V.

(b) VPA is higher than 0.4 V but below 3.45 V.

  • Accelerator pedal sensor assembly

  • Open in EPA2 circuit

  • Accelerator pedal sensor assembly deformed

  • ECM

Comes on

DTC stored

P2138

Throttle / Pedal Position Sensor / Switch "D" / "E" Voltage Correlation

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

(a) The difference between VPA and VPA2 is below 0.02 V.

(b) VPA is below 0.4 V and VPA2 is below 1.2 V.

  • Accelerator pedal sensor assembly

  • VPA and VPA2 circuits are short-circuited

  • Accelerator pedal sensor assembly deformed

  • ECM

Comes on

DTC stored
Table 1. Related Data List

DTC No.

Data List

P2120

  • Accel Position

  • Accel Sens. No.1 Volt %

  • Accel Sens. No.2 Volt %

P2122

P2123

P2125

P2127

P2128

P2138

CONFIRMATION DRIVING PATTERN

DTC No.

DTC Detection Drive Pattern

P2120

Ignition switch ON

  • Accelerator pedal fully closed for 3 seconds

  • Accelerator pedal open partway for 3 seconds

  • Accelerator pedal fully open for 3 seconds

P2122

P2123

P2125

P2127

P2128

P2138

WIRING DIAGRAM

A149601E33

CAUTION / NOTICE / HINT

Note:

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

Tip:

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. READ VALUE USING GTS (ACCELERATOR PEDAL POSITION)

    1. Connect the GTS to the DLC3.

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

    3. Enter the following menus: Powertrain / Engine / Data List / Accel Sens. No.1 Volt % and Accel Sens. No.2 Volt %.

      Powertrain > Engine > Data List

      Tester Display

      Accel Sens. No.1 Volt %

      Accel Sens. No.2 Volt %

    4. Read the values.

      Standard Voltage

      Accelerator Pedal

      Accel Sens. No.1 Volt %

      Accel Sens. No.2 Volt %

      Released

      10 to 22%

      24 to 40%

      Depressed

      52 to 90%

      68 to 95%

      Result

      Proceed to

      A

      B
    B

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIREDClick here

    A

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

    1. Disconnect the accelerator pedal sensor 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

      A6-1 (VCP2) - A61-57 (VCP2)

      Always

      Below 1 Ω

      A6-2 (EPA2) - A61-58 (EPA2)

      Always

      Below 1 Ω

      A6-3 (VPA2) - A61-54 (VPA2)

      Always

      Below 1 Ω

      A6-4 (VCPA) - A61-55 (VCPA)

      Always

      Below 1 Ω

      A6-5 (EPA) - A61-56 (EPA)

      Always

      Below 1 Ω

      A6-6 (VPA) - A61-53 (VPA)

      Always

      Below 1 Ω

      A6-1 (VCP2) or A61-57 (VCP2) - Body ground

      Always

      10 kΩ or higher

      A6-2 (EPA2) or A61-58 (EPA2) - Body ground

      Always

      10 kΩ or higher

      A6-3 (VPA2) or A61-54 (VPA2) - Body ground

      Always

      10 kΩ or higher

      A6-4 (VCPA) or A61-55 (VCPA) - Body ground

      Always

      10 kΩ or higher

      A6-5 (EPA) or A61-56 (EPA) - Body ground

      Always

      10 kΩ or higher

      A6-6 (VPA) or A61-53 (VPA) - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTORClick here

    OK

  3. INSPECT ECM TERMINAL VOLTAGE (VCPA AND VCP2 TERMINALS)

    1. A200914C06

      *a

      Front view of wire harness connector

      (to Accelerator Pedal Sensor Assembly)

      Disconnect the accelerator pedal sensor assembly connector.

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

      Standard Voltage

      Tester Connection

      Switch Condition

      Specified Condition

      A6-4 (VCPA) - A6-5 (EPA)

      Ignition switch ON

      4.5 to 5.5 V

      A6-1 (VCP2) - A6-2 (EPA2)

      Ignition switch ON

      4.5 to 5.5 V

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE ECMClick here

    OK

  4. REPLACE ACCELERATOR PEDAL ROD ASSEMBLY

    1. Replace the accelerator pedal sensor assembly.

      Click here

    Result

    Proceed to

    NEXT
    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIREDClick here

  5. REPLACE ECM

    1. Replace the ECM.

      Click here

    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

  7. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Clear the DTCs.

      Powertrain > Engine > Clear DTCs

    5. Turn the ignition switch off and leave the vehicle for 30 seconds.

    6. Turn the ignition switch to ON.

    7. Fully close the accelerator pedal for 3 seconds or more, then hold it partway open for 3 seconds or more, and then fully open it for 3 seconds or more.

    8. Enter the following menus: Powertrain / Engine / Trouble Codes.

      Powertrain > Engine > Trouble Codes

    9. Confirm that the DTC is not output again.

    Result

    Proceed to

    NEXT
    NEXT

    END