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

CAUTION / NOTICE / HINT

Tech Tips

These DTCs relate to the throttle position sensor.

DESCRIPTION

The throttle position sensor is mounted on the throttle body assembly, and detects the opening angle of the throttle valve. This sensor is a non-contact type. It uses Hall-effect elements in order to yield accurate signals even in extreme driving conditions such as at high speeds and very low speeds.

The throttle position sensor has two sensor circuits which each 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.

A005TC8E01
DTC No. DTC Detection Condition Trouble Area
P0120

Output voltage of VTA1 quickly fluctuates beyond lower and upper malfunction thresholds for 2 seconds when accelerator pedal is depressed

(1 trip detection logic)


  • Throttle position sensor (built into throttle body assembly)


  • ECM

P0121

Difference between 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 assembly)
P0122

Output voltage of VTA1 0.2 V or less for 2 seconds when accelerator pedal is depressed

(1 trip detection logic)


  • Throttle position sensor (built into throttle body assembly)


  • Short in VTA1 circuit


  • Open in VC circuit


  • ECM

P0123

Output voltage of VTA1 4.535 V or more for 2 seconds when accelerator pedal is depressed

(1 trip detection logic)


  • Throttle position sensor (built into throttle body assembly)


  • Open in VTA1 circuit


  • Open in E2 circuit


  • Short between VC and VTA1 circuit


  • ECM

P0220

Output voltage of VTA2 quickly fluctuates beyond lower and upper malfunction thresholds for 2 seconds when accelerator pedal is depressed

(1 trip detection logic)


  • Throttle position sensor (built into throttle body assembly)


  • ECM

P0222

Output voltage of VTA2 1.75 V or less for 2 seconds when accelerator pedal is depressed

(1 trip detection logic)


  • Throttle position sensor (built into throttle body assembly)


  • 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 when accelerator pedal is depressed

(1 trip detection logic)


  • Throttle position sensor (built into throttle body assembly)


  • Open in VTA2 circuit


  • Open in E2 circuit


  • Short between VC and VTA2 circuit


  • 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 1.75 V or less, for 0.4 seconds or more


  • Short between VTA1 and VTA2 circuit


  • Throttle position sensor (built into throttle body assembly)


  • ECM

Tech Tips


  • When any of these DTCs are output, check the throttle valve opening angle by entering the following menus on the intelligent tester: Powertrain / Engine and ECT / Data List / 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 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, and the throttle valve is returned to a 5.5° 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 gently, the vehicle can be driven slowly. Fail-safe mode continues until a pass condition is detected, and the ignition switch is then turned off.

WIRING DIAGRAM

A005UQDE05

INSPECTION PROCEDURE

Tech Tips

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 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 ground short

      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 ground short
      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 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 stored. 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 the "CHECK HARNESS AND CONNECTOR (THROTTLE POSITION SENSOR - ECM)".


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


    1. A005W2RE05
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Throttle Body)

      *2

      Front view of wire harness connector

      (to ECM)

      Disconnect the throttle body 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
      B7-5 (VC) - B39-89 (VCTA) Always Below 1 Ω
      B7-6 (VTA) - B39-113 (VTA1) Always Below 1 Ω
      B7-4 (VTA2) - B39-112 (VTA2) Always Below 1 Ω
      B7-3 (E2) - B39-90 (ETA) Always Below 1 Ω
      Standard Resistance (Check for short)
      Tester Connection Condition Specified Condition
      B7-5 (VC) or B39-89 (VCTA) - Body ground Always 10 kΩ or higher
      B7-6 (VTA) or B39-113 (VTA1) - Body ground Always 10 kΩ or higher
      B7-4 (VTA2) or B39-112 (VTA2) - Body ground Always 10 kΩ or higher
    4. Reconnect the throttle body connector.

    5. Reconnect the ECM connector.


    NG
    OK
  3. INSPECT ECM (VC VOLTAGE)


    1. A005V4DE02
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Throttle Body)

      Disconnect the throttle body connector.

    2. Turn the ignition switch to ON.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      B7-5 (VC) - B7-3 (E2) Ignition switch ON 4.5 to 5.5 V
    4. Reconnect the throttle body connector.


    NG
    OK
  4. REPLACE THROTTLE BODY ASSEMBLY


    1. Replace throttle 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 to ON 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. Enter the following menus: Powertrain / Engine and ECT / DTC.

    7. Read the DTCs.

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

    B
    A