SFI SYSTEM, Diagnostic DTC:P0120, P0121, P0122, P0123, P0220, P0222, P0223, P2135

DTC Code DTC Name
P0120 Throttle / Pedal Position Sensor / Switch "A" Circuit Malfunction
P0121 Throttle / Pedal Position Sensor / Switch "A" Circuit Range / Performance Problem
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.

The throttle position sensor is built into the throttle body with motor assembly and detects the opening angle of the throttle valve. This sensor is a non-contact type sensor. It 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 throttle position sensor has 2 sensor circuits, each of which transmits a signal, VTA1 and VTA2. VTA1 is used to detect the throttle valve angle and VTA2 is used to detect malfunctions in VTA1. The sensor signal voltages vary between 0 V and 5 V in proportion to the throttle valve opening angle, and are transmitted to the VTA terminals of the ECM.

As the valve closes, the sensor output voltage decreases and as the valve opens, the sensor output voltage increases. The ECM calculates the throttle valve opening angle according to these signals and controls the throttle actuator in response to driver inputs. These signals are also used in calculations such as air fuel ratio correction, power increase correction and fuel-cut control.

A0095VWE34
DTC No. DTC Detection Condition Trouble Area
P0120 The output voltage of VTA1 quickly fluctuates beyond the upper and lower malfunction thresholds for 2 seconds or more (1-trip detection logic).
  • Throttle position sensor (built into throttle body with motor assembly)

  • ECM

P0121 The difference between the VTA1 and VTA2 voltages is less than 0.8 V, or more than 1.6 V for 2 seconds (1-trip detection logic).
  • Throttle position sensor (built into throttle body with motor assembly)

  • Throttle position sensor circuit

  • ECM

P0122 The output voltage of VTA1 is 0.2 V or less for 2 seconds or more (1-trip detection logic).
  • Throttle position sensor (built into throttle body with motor assembly)

  • Short in VTA1 circuit

  • Open in VC circuit

  • ECM

P0123 The output voltage of VTA1 is 4.54 V or higher for 2 seconds or more (1-trip detection logic).
  • Throttle position sensor (built into throttle body with motor assembly)

  • Open in VTA1 circuit

  • Open in E2 circuit

  • Short between VC and VTA1 circuit

  • ECM

P0220 The output voltage of VTA2 quickly fluctuates beyond the upper and lower malfunction thresholds for 2 seconds or more (1-trip detection logic).
  • Throttle position sensor (built into throttle body with motor assembly)

  • ECM

P0222 The output voltage of VTA2 is 1.75 V or less for 2 seconds or more (1-trip detection logic).
  • Throttle position sensor (built into throttle body with motor assembly)

  • Short in VTA2 circuit

  • Open in VC circuit

  • ECM

P0223 The output voltage of VTA2 is 4.8 V or higher and VTA1 is between 0.2 V and 2.02 V for 2 seconds or more (1-trip detection logic).
  • Throttle position sensor (built into throttle body with motor assembly)

  • Open in VTA2 circuit

  • Open in E2 circuit

  • Short between VC and VTA2 circuit

  • ECM

P2135

Either condition is met (1-trip detection logic):

(a) The difference between the output voltages of VTA1 and VTA2 is 0.02 V or less for 0.5 seconds or more.

(b) The output voltage of VTA1 is 0.2 V or less and VTA2 is 1.75 V or less for 0.4 seconds or more.


  • Short between VTA1 and VTA2 circuits

  • Throttle position sensor (built into throttle body with motor assembly)

  • ECM

Tech Tips


  • When any of these DTCs are output, check the throttle valve opening angle using the intelligent tester.

    Enter the following menus: Powertrain / Engine and ECT / Data List / ETCS / Throttle Position No.1 and Throttle Position No.2.

  • Throttle Position No.1 is the VTA1 signal, and Throttle Position No.2 is the VTA2 signal.

Reference (Normal Condition)
Tester Display Accelerator Pedal Fully Released Accelerator Pedal Fully Depressed
Throttle Position No.1 0.5 to 1.1 V 3.2 to 4.8 V
Throttle Position No.2 2.1 to 3.1 V 4.6 to 5.0 V

FAIL-SAFE

When any of these DTCs as well as other DTCs relating to ETCS (Electronic Throttle Control System) malfunctions are stored, the ECM enters fail-safe mode. During fail-safe mode, the ECM cuts the current to the throttle actuator and the throttle valve is returned to a 6.5° opening 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 position to allow the vehicle to continue at a minimal speed. If the accelerator pedal is depressed firmly and gently, the vehicle can be driven slowly.

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

WIRING DIAGRAM

A009BL5E04

INSPECTION PROCEDURE

Tech Tips

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 (THROTTLE POSITION NO.1 AND THROTTLE POSITION NO.2)


    1. Connect the intelligent tester to the DLC3.

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

    3. Enter the following menus: Powertrain / Engine and ECT / Data List / Throttle Position No. 1 and Throttle Position No. 2.

    4. Read the values displayed on the tester.

      Result
      Throttle Position No. 1 (VTA1) when Accelerator Pedal Released Throttle Position No.2 (VTA2) when Accelerator Pedal Released Throttle Position No. 1 (VTA1) when Accelerator Pedal Depressed Throttle Position No.2 (VTA2) when Accelerator Pedal Depressed Trouble Area Proceed to
      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

      2.1 V to 3.1 V

      (Fail-safe)

      0 V to 0.2 V, or 4.5 V to 5.0 V

      2.1 V to 3.1 V

      (Fail-safe)

      VTA1 circuit open or short to ground

      0.6 V to 1.4 V

      (Fail-safe)

      0 V to 0.2 V, or 4.5 V to 5.0 V

      0.6 V to 1.4 V

      (Fail-safe)

      0 V to 0.2 V, or 4.5 V to 5.0 V VTA2 circuit open or short to ground
      0.5 V to 1.1 V 2.1 V to 3.1 V

      3.2 V to 4.8 V

      (Not fail-safe)

      4.6 V to 5.0 V

      (Not fail-safe)

      Throttle position sensor circuit normal B

      Tech Tips


      • DTC P0121/41 is stored when the VTA1 and VTA2 output voltages are not consistent with the sensor characteristics. Therefore, check the freeze frame data when this DTC is output. Use the following formula to confirm the relative differences in voltage.


        • Characteristic Sensor Output:
        • VTA2 x 0.8 is approximately equal to VTA1 + 1.11 V

        • VTA1: Throttle Position No. 1

        • VTA2: Throttle Position No. 2

      • If DTC P0121 is output, proceed to "Check Harness and Connector (Throttle Position Sensor - ECM)".


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


    1. Disconnect the throttle body with motor assembly 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
      C13-5 (VC) - C61-10 (VCTA) Always Below 1 Ω
      C13-6 (VTA) - C61-3 (VTA1) Always Below 1 Ω
      C13-4 (VTA2) - C61-4 (VTA2) Always Below 1 Ω
      C13-3 (E2) - C61-9 (ETA) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      C13-5 (VC) or C61-10 (VCTA) - Body ground Always 10 kΩ or higher
      C13-6 (VTA) or C61-3 (VTA1) - Body ground Always 10 kΩ or higher
      C13-4 (VTA2) or C61-4 (VTA2) - Body ground Always 10 kΩ or higher
    4. Reconnect the throttle body with motor assembly connector.

    5. Reconnect the ECM connector.


    NG
    OK
  3. INSPECT ECM (VC VOLTAGE)


    1. A009BMIE03
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Throttle Body with Motor Assembly)

      Disconnect the throttle body with motor assembly connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      C13-5 (VC) - C13-3 (E2) Ignition switch ON 4.5 to 5.5 V
    3. Reconnect the throttle body with motor assembly connector.


    NG
    OK
  4. REPLACE THROTTLE BODY WITH MOTOR ASSEMBLY


    1. Replace the throttle body with motor 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 to ON.

    3. Turn the tester on.

    4. Clear the DTCs Click here.

    5. Start the engine.

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

    7. Enter the following menus: Powertrain / Engine and ECT / DTC.

    8. Read the DTCs.

      Result
      Result Proceed to
      DTC P0120, P0121, P0122, P0123, P0220, P0222, P0223 and/or P2135 is output A
      DTC is not output B

    B
    A