SFI SYSTEM, Diagnostic DTC:P0120, P0122, P0123, P0220, P0222, P0223, P2135

DTC Code DTC Name
P0120 Throttle / Pedal Position Sensor / Switch "A" Circuit
P0122 Throttle / Pedal Position Sensor / Switch "A" Circuit Low Input
P0123 Throttle / Pedal Position Sensor / Switch "A" Circuit High Input
P0220 Throttle / Pedal Position Sensor / Switch "B" Circuit
P0222 Throttle / Pedal Position Sensor / Switch "B" Circuit Low Input
P0223 Throttle / Pedal Position Sensor / Switch "B" Circuit High Input
P2135 Throttle / Pedal Position Sensor / Switch "A" / "B" Voltage Correlation

DESCRIPTION

Tech Tips

These DTCs relate to the throttle position sensor.

This electronic throttle control system does not use a throttle cable.

The accelerator pedal position sensor is integrated with 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 V and 5 V in proportion to the operating angle of the accelerator pedal (throttle valve). A signal from VPA indicates the actual accelerator pedal opening angle (throttle valve opening angle) and is used for engine control. A 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 opening angle (throttle valve opening angle) through the signals from VPA and VPA2, and controls the throttle actuator according to these signals.

A017FQIE79
DTC No. DTC Detection Condition Trouble Area
P0120 Output voltage of VTA1 quickly fluctuates beyond lower and upper malfunction thresholds for 2 seconds (1 trip detection logic)

  • Throttle position sensor (built into throttle body)

  • ECM
P0122 Output voltage of VTA1 is 0.2 V or less for 2 seconds (1 trip detection logic)

  • Throttle position sensor (built into throttle body)

  • Short in VTA1 circuit

  • Open in VC circuit

  • ECM
P0123 Output voltage of VTA1 is 4.535 V or more for 2 seconds (1 trip detection logic)

  • Throttle position sensor (built into throttle body)

  • Open in VTA1 circuit

  • Open in E2 circuit

  • Short between VC and VTA1 circuits

  • ECM
P0220 Output voltage of VTA2 quickly fluctuates beyond lower and upper malfunction thresholds for 2 seconds (1 trip detection logic)

  • Throttle position sensor (built into throttle body)

  • ECM
P0222 Output voltage of VTA2 is 1.75 V or less for 2 seconds (1 trip detection logic)

  • Throttle position sensor (built into throttle body)

  • Short in VTA2 circuit

  • Open in VC circuit

  • ECM
P0223 Output voltage of VTA2 is 4.8 V or more, and VTA1 is between 0.2 V and 2.02 V, for 2 seconds (1 trip detection logic)

  • Throttle position sensor (built into throttle body)

  • Open in VTA2 circuit

  • Open in E2 circuit

  • Short between VC and VTA2 circuits

  • ECM
P2135

Either condition (a) or (b) is met (1 trip detection logic):

(a) Difference between output voltages of VTA1 and VTA2 is 0.02 V or less for 0.5 seconds or more

(b) Output voltage of VTA1 is 0.2 V or less, and VTA2 is 0.5 V or less, for 0.4 seconds or more

  • Short between VTA1 and VTA2 circuits

  • Throttle position sensor (built into throttle body)

  • ECM

Tech Tips


  • When any of these DTCs are set, check the throttle valve opening angle by selecting the following menu items on the intelligent tester: Powertrain / Engine and ECT / Data List / Throttle Position No. 1 and Throttle Position No. 2.

  • Throttle Position No. 1 denotes the VTA1 signal (expressed in percentages), and Throttle Position No. 2 denotes the VTA2 signal (expressed in voltages).

Reference (Normal Condition):
Tester Display Accelerator Pedal Fully Released Accelerator Pedal Fully Depressed
Throttle Position No. 1 0.5 to 1.1 V 3.3 to 4.9 V
Throttle Position No. 2 2.1 to 3.1 V 4.5 to 5.0 V

FAIL-SAFE

When any of these DTCs, as well as other DTCs relating to electronic throttle control system malfunctions, are set, the ECM enters fail-safe mode. During fail-safe mode, the ECM cuts the current to the throttle actuator off, and the throttle valve is returned to a 6° throttle angle by the return spring. The ECM then adjusts the engine output by controlling the fuel injection (intermittent fuel-cut) and ignition timing, in accordance with the accelerator pedal opening angle, to allow the vehicle to continue at a minimal speed. If the accelerator pedal is depressed slowly, the vehicle can be driven slowly.

Fail-safe mode continues until a pass condition is detected, and the ignition switch is turned off.

WIRING DIAGRAM

A017D35E29

INSPECTION PROCEDURE

Tech Tips


  • If other DTCs relating to different systems that have terminal E2 as the ground terminal are output simultaneously, terminal E2 may have an open circuit.

  • Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.

PROCEDURE


  1. READ VALUE USING INTELLIGENT TESTER (THROTTLE POS AND THROTTLE POS #2)


    1. Connect the intelligent tester to the DLC3.

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

    3. Select the following menu items: Powertrain / Engine and ECT / Data List / Throttle Position No. 1 and Throttle Position No. 2.

    4. Check the values displayed on the tester.

      Result
      When Accelerator Pedal Released When Accelerator Pedal Depressed Trouble Area Proceed to
      Throttle Position No. 1 (VTA1) Throttle Position No. 2 (VTA2) Throttle Position No. 1 (VTA1) Throttle Position No. 2 (VTA2)
      0 V to 0.2 V 0 V to 0.2 V 0 V to 0.2 V 0 V to 0.2 V VC circuit open A
      4.5 V to 5.0 V 4.5 V to 5.0 V 4.5 V to 5.0 V 4.5 V to 5.0 V E2 circuit open
      0 V to 0.2 V, or 4.5 V to 5.0 V 2.4 to 3.4 V (Fail-safe) 0 V to 0.2 V, or 4.5 V to 5.0 V 2.4 to 3.4 V (Fail-safe) VTA1 circuit open or ground short
      0.7 V to 1.3 V (Fail-safe) 0 V to 0.2 V, or 4.5 V to 5.0 V 0.7 V to 1.3 V (Fail-safe) 0 V to 0.2 V, or 4.5 V to 5.0 V VTA2 circuit open or ground short
      0.5 V to 1.1 V 2.1 V to 3.1 V 3.3 V to 4.9 V (Not fail-safe) 4.6 V to 5.0 V (Not fail-safe) Throttle position sensor circuit normal B

    B

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

    A

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


    1. A017D2ZE02

      Disconnect the throttle position sensor connector.

    2. Disconnect the ECM connector.

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

      Standard resistance (Check for open)
      Tester Connection Condition Specified Condition
      B27-5 (VC) - B1-23 (VC) Always Below 1 Ω
      B27-6 (VTA) - B1-20 (VTA) Always Below 1 Ω
      B27-4 (VTA2) - B1-19 (VTA2) Always Below 1 Ω
      B27-3 (E2) - B1-28 (E2) Always Below 1 Ω
      Standard resistance (Check for short)
      Tester Connection Condition Specified Condition
      B27-5 (VC) or B1-23 (VC) - Body ground Always 10 kΩ or higher
      B27-6 (VTA) or B1-20 (VTA) - Body ground Always 10 kΩ or higher
      B27-4 (VTA2) or B1-19 (VTA2) - Body ground Always 10 kΩ or higher

    4. Reconnect the throttle position sensor connector.

    5. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. INSPECT ECM (VC VOLTAGE)


    1. A017BQGE15

      Turn the ignition switch on (IG).

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

      Standard voltage
      Tester Connection Switch Condition Specified Condition
      B1-23 (VC) - B1-28 (E2) Ignition switch on (IG) 4.5 to 5.0 V

    NG

    REPLACE ECM Click here

    OK

  4. REPLACE THROTTLE WITH MOTOR BODY ASSEMBLY


    1. Replace the throttle with motor body assembly Click here.


    NEXT

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


    1. Connect the intelligent tester to the DLC3.

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

    3. Clear the DTCs Click here.

    4. Start the engine.

    5. Allow the engine to idle for 15 seconds or more.

    6. Select the following menu items: Powertrain / Engine and ECT / DTC.

    7. Read the DTCs.

      Result
      Display (DTC Output) Proceed to
      P0120, P0122, P0123, P0220, P0222, P0223 and/or P2135 A
      No output B

    B

    SYSTEM OK

    A

    REPLACE ECM Click here