SFI SYSTEM(w/o EGR 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

CAUTION / NOTICE / HINT

DESCRIPTION

The accelerator pedal position sensor assembly is mounted on the accelerator pedal bracket 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 4.5 V in proportion to 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.

Tip:

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

A280874E01

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Memory

P2120

Throttle / Pedal Position Sensor / Switch "D" Circuit

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

  • Accelerator pedal position sensor assembly

  • ECM

Comes on

DTC stored

P2122

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

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 assembly

  • Open in VCP1 circuit

  • Open or ground short in VPA circuit

  • ECM

Comes on

DTC stored

P2123

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

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

  • Accelerator pedal position sensor assembly

  • Open in EPA circuit

  • ECM

Comes on

DTC stored

P2125

Throttle / Pedal Position Sensor / Switch "E" Circuit

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

  • Accelerator pedal position sensor assembly

  • ECM

Comes on

DTC stored

P2127

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

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 assembly

  • Open in VCP2 circuit

  • Open or ground short in VPA2 circuit

  • ECM

Comes on

DTC stored

P2128

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

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 assembly

  • Open in EPA2 circuit

  • ECM

Comes on

DTC stored

P2138

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

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 assembly

  • ECM

Comes on

DTC stored
Tip:

When any of these DTCs are 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 ground short in VPA circuit

0 to 0.2 V

1.2 to 2.0 V

0 to 0.2 V

3.4 to 4.7 V

Open or ground short 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 5.0 V

4.5 to 5.0 V

4.5 to 5.0 V

4.5 to 5.0 V

Normal condition

0.5 to 1.1 V

1.2 to 2.0 V

2.6 to 4.5 V

3.4 to 4.7 V
Tip:

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.

CONFIRMATION DRIVING PATTERN

A199317E23

  1. Connect the intelligent tester to the DLC3.

  2. Turn the engine switch on (IG) and turn the tester on.

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

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

  5. Turn the engine switch on (IG) and turn the tester on [A].

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

  7. Check that 5 seconds or more have elapsed since the engine switch was turned on (IG).

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

  9. Read the pending DTCs.

    Tip:

    • 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.

    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

    UNKNOWN

    • Unable to perform DTC judgment

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

    • 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 UNKNOWN, perform steps [B] through [C] again.

FAIL-SAFE

When DTC P2120, P2121, P2122, P2123, P2125, P2127, P2128 or P2138 is stored, the ECM enters fail-safe mode. If either of the 2 sensor circuits malfunctions, the ECM uses the remaining circuit to calculate the accelerator pedal position to allow the vehicle to continue driving. If both of the circuits malfunction, the ECM regards the accelerator pedal as being released. As a result, the throttle valve is closed and the engine idles.

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

WIRING DIAGRAM

A185023E06

CAUTION / NOTICE / HINT

Tip:

  • 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)

    1. A208621C01

      *a

      Depressed

      *b

      Released

      Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the 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.

      Powertrain > Engine and ECT > Data List

      Tester Display

      Accel Sensor Out No.1

      Accel Sensor Out No.2

    5. Read the value displayed on the 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 4.7 V

      Result

      Result

      OK

      NG
    OK

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

    NG

  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

      A16-6 (VPA) - G45-6 (VPA)

      Always

      Below 1 Ω

      A16-5 (EPA) - G45-3 (EPA)

      Always

      Below 1 Ω

      A16-4 (VCPA) - G45-4 (VCPA)

      Always

      Below 1 Ω

      A16-3 (VPA2) - G45-5 (VPA2)

      Always

      Below 1 Ω

      A16-2 (EPA2) - G45-1 (EPA2)

      Always

      Below 1 Ω

      A16-1 (VCP2) - G45-2 (VCP2)

      Always

      Below 1 Ω

      A16-6 (VPA) or G45-6 (VPA) - Body ground

      Always

      10 kΩ or higher

      A16-5 (EPA) or G45-3 (EPA) - Body ground

      Always

      10 kΩ or higher

      A16-4 (VCPA) or G45-4 (VCPA) - Body ground

      Always

      10 kΩ or higher

      A16-3 (VPA2) or G45-5 (VPA2) - Body ground

      Always

      10 kΩ or higher

      A16-2 (EPA2) or G45-1 (EPA2) - Body ground

      Always

      10 kΩ or higher

      A16-1 (VCP2) or G45-2 (VCP2) - Body ground

      Always

      10 kΩ or higher

      Result

      Result

      OK

      NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. INSPECT ECM (VCPA AND VCP2 VOLTAGE)

    1. A115666C02

      *a

      Front view of wire harness connector

      (to Accelerator Pedal Position Sensor Assembly)

      Disconnect the accelerator pedal position sensor connector.

    2. Turn the engine switch on (IG).

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

      Standard Voltage

      Tester Connection

      Switch Condition

      Specified Condition

      A16-4 (VCPA) - A16-5 (EPA)

      Engine switch on (IG)

      4.5 to 5.5 V

      A16-1 (VCP2) - A16-2 (EPA2)

      Engine switch on (IG)

      4.5 to 5.5 V

      Result

      Result

      OK

      NG
    NG

    REPLACE ECM

    Click here

    OK

  4. REPLACE ACCELERATOR PEDAL POSITION SENSOR ASSEMBLY

    1. Replace the accelerator pedal position sensor assembly.

      Click here

      Result

      Result

      NEXT
    NEXT

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

    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the tester on.

    4. Clear the DTCs.

      Click here

      Powertrain > Engine and ECT > Clear DTCs

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

    6. Read DTCs.

      Powertrain > Engine and ECT > Trouble Codes

      Result

      Result

      Proceed to

      P2120, P2122, P2123, P2125, P2127, P2128 and/or P2138 is output

      A

      No DTC is output

      B
    A

    REPLACE ECM

    Click here

    B

    END