SFI SYSTEM (w/ EGR 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 mounted on the throttle with motor body 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 VTA1 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.

A01NF2CE03
DTC No. DTC Detection Condition Trouble Area
P0120

The 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 with motor body assembly)

  • ECM
P0121

The difference between the VTA1 and VTA2 voltages is below 0.8 V or higher than 1.6 V for 2 seconds

(1 trip detection logic)

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

  • Throttle position sensor circuit

  • ECM
P0122

The output voltage of VTA1 is 0.2 V or less for 2 seconds

(1 trip detection logic)

  • Throttle position sensor (built into throttle with motor body 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

(1 trip detection logic)

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

  • Open in VTA1 circuit

  • Open in E2 circuit

  • Short between VC and VTA1 circuits

  • ECM
P0220

The output voltage of VTA2 quickly fluctuates beyond the lower and upper malfunction thresholds for 2 seconds

(1 trip detection logic)

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

  • ECM
P0222

The output voltage of VTA2 is 1.75 V or less for 2 seconds

(1 trip detection logic)

  • Throttle position sensor (built into throttle with motor body 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 (1 trip detection logic)

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

  • Open in VTA2 circuit

  • Open in E2 circuit

  • Short between VC and VTA2 circuits

  • ECM
P2135

Either of the following conditions 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

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

  • Short between VTA1 and VTA2 circuits

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

  • ECM

CONFIRMATION DRIVING PATTERN

A01NG89E04

  1. Connect the intelligent tester to the DLC3.

  2. Turn the power switch on (IG).

  3. Turn the tester on.

  4. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure) Click here.

  5. Turn the power switch off.

  6. Turn the power switch on (IG) and turn the tester on [A].

  7. Put the engine in inspection mode Click here.

  8. Start the engine.

  9. With the vehicle stationary, fully depress and release the accelerator pedal [B].

  10. Idle the engine for 2 seconds or more [C].

  11. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

  12. Input the DTC: P0120, P0121, P0122, P0123, P0220, P0222, P0223 or P2135.

  13. Check the DTC judgment result [D].

    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's memory limit

    Tech Tips


    • If the judgment result shows ABNORMAL, the system has a malfunction.

    • If the judgment result shows INCOMPLETE or UNKNOWN, perform steps [B] and [D] again.

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 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 firmly and gently, the vehicle can be driven slowly.

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

WIRING DIAGRAM

A01NGYCE15

INSPECTION PROCEDURE

Tech Tips


  • DTC P0121 is stored when the voltages output from VTA1 and VTA2 are not consistent with the characteristics of the sensors. Therefore, check the Freeze Frame Data when this DTC is output. Use the following formula to confirm relative fluctuations in voltage.

    Features of 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)".

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


    1. Disconnect the throttle with motor body assembly connector.

      A01NEB9E04

    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
      D28-5 (VC) - D1-118 (VCTA) Always Below 1 Ω
      D28-6 (VTA) - D1-85 (VTA1) Always Below 1 Ω
      D28-4 (VTA2) - D1-86 (VTA2) Always Below 1 Ω
      D28-3 (E2) - D1-119 (ETA) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      D28-5 (VC) or D1-118 (VCTA) - Body ground Always 10 kΩ or higher
      D28-6 (VTA) or D1-85 (VTA1) - Body ground Always 10 kΩ or higher
      D28-4 (VTA2) or D1-86 (VTA2) - Body ground Always 10 kΩ or higher
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Throttle Position Sensor)

      		 *2

      Front view of wire harness connector

      (to ECM)

    4. Reconnect the ECM connector.

    5. Reconnect the throttle with motor body assembly connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (THROTTLE POSITION SENSOR - ECM)

    OK

  2. INSPECT ECM (VC VOLTAGE)


    1. A01NDJHE08
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Throttle Position Sensor)

      Disconnect the throttle with motor body assembly connector.

    2. Turn the power switch on (IG).

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      D28-5 (VC) - D28-3 (E2) Power switch on (IG) 4.5 to 5.5 V

    4. Reconnect the throttle with motor body assembly connector.


    NG

    REPLACE ECM Click here

    OK

  3. REPLACE THROTTLE WITH MOTOR BODY ASSEMBLY


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


    NEXT

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


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Clear the DTCs Click here.

    5. Put the engine in inspection mode Click here.

    6. Start the engine.

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

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

    9. 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

    END

    A

    REPLACE ECM Click here