Dtc P2121 Throttle / Pedal Position Sensor / Switch D Circuit Range / Performance

Engine. Lexus Is250, Is220D. Gse20 Ale20
2Ad-Fhv Engine Control System. Lexus Is250, Is220D. Gse20 Ale20

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

READ VALUE OF INTELLIGENT TESTER (ACCELERATOR PEDAL POSITION SENSOR VALUE)

CHECK HARNESS AND CONNECTOR (ACCELERATOR PEDAL POSITION SENSOR - ECM)

DTC P2121 Throttle / Pedal Position Sensor / Switch "D" Circuit Range / Performance


DESCRIPTION

HINT:
  1. This is the repair procedure for the accelerator pedal position sensor.
  2. This electrical throttle system does not use a throttle cable.
  3. This accelerator pedal position sensor is a non-contact type.
The accelerator pedal position sensor is mounted on the accelerator pedal and detects the opening angle of the accelerator pedal. Since this sensor is electronically controlled with Hall-effect elements, accurate control and reliability can be obtained. It has 2 sensors to detect both the accelerator position and a malfunction of the accelerator position sensor.
In the accelerator pedal position sensor, the voltage applied to pedal terminals VPA and VPA2 of the ECM changes between 0 V and 5 V in proportion to the opening angle of the accelerator pedal. The VPA is a signal to indicate the actual accelerator pedal opening angle which is used for the engine control, and the VPA2 is a signal to indicate the information about the opening angle which is used for detecting malfunctions. The ECM determines the current opening angle of the accelerator pedal using signals from terminals VPA and VPA2, and the ECM controls the throttle motor based on these signals.

Lexus Is250, Is220D. Gse20 Ale20.2Ad-Fhv Engine Control System.Ecd System. Dtc P2121 Throttle / Pedal Position Sensor / Switch D Circuit Range / Performance


DTC No.
DTC Detection Condition
Trouble Area
P2121
Condition (a) continues for 2 seconds:
(a) Difference between VPA1 and VPA2 exceeds the threshold
(1 trip detection logic)
  1. Accelerator pedal position sensor circuit
  2. Accelerator pedal position sensor
  3. ECM

WIRING DIAGRAM


Lexus Is250, Is220D. Gse20 Ale20.2Ad-Fhv Engine Control System.Ecd System. Dtc P2121 Throttle / Pedal Position Sensor / Switch D Circuit Range / Performance


INSPECTION PROCEDURE

NOTICE:
After replacing the ECM, the new ECM needs registration (Click here) and initialization (Click here).
1.READ VALUE OF INTELLIGENT TESTER (ACCELERATOR PEDAL POSITION SENSOR VALUE)


    Lexus Is250, Is220D. Gse20 Ale20.2Ad-Fhv Engine Control System.Ecd System. Dtc P2121 Throttle / Pedal Position Sensor / Switch D Circuit Range / Performance

  1. Connect the intelligent tester to the DLC3.

  1. Turn the engine switch ON (IG) and turn the intelligent tester ON.

  1. Enter the following menus: Powertrain / Engine / Data List / Accel Position 1 and Accel Position 2.

  1. Read the values.

    Standard voltage:
    Accelerator Pedal
    		Accel Position 1
    		Accel Position 2
    Released
    		0.5 to 1.1 V
    		0.9 to 2.3 V
    Depressed
    		3.0 to 4.6 V
    		3.4 to 5.0 V


OK
REPLACE ECM
NG


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


    Lexus Is250, Is220D. Gse20 Ale20.2Ad-Fhv Engine Control System.Ecd System. Dtc P2121 Throttle / Pedal Position Sensor / Switch D Circuit Range / Performance

  1. Disconnect the A26 sensor connector.

  1. Disconnect the A49 ECM connector.

  1. Measure the resistance of the wire harness side connectors.

    Standard resistance:
    Tester Connection
    		Specified Condition
    VCP2 (A26-1) - VCP2 (A49-56)
    		Below 1 Ω
    EPA2 (A26-2) - EPA2 (A49-58)
    		Below 1 Ω
    VPA2 (A26-3) - VPA2 (A49-54)
    		Below 1 Ω
    VCPA (A26-4) - VCPA (A49-55)
    		Below 1 Ω
    EPA (A26-5) - EPA (A49-57)
    		Below 1 Ω
    VPA (A26-6) - VPA (A49-53)
    		Below 1 Ω
    VCP2 (A26-1) or VCP2 (A49-56) - Body ground
    		10 kΩ or higher
    EPA2 (A26-2) or EPA2 (A49-58) - Body ground
    		10 kΩ or higher
    VPA2 (A26-3) or VPA2 (A49-54) - Body ground
    		10 kΩ or higher
    VCPA (A26-4) or VCPA (A49-55) - Body ground
    		10 kΩ or higher
    EPA (A26-5) or EPA (A49-57) - Body ground
    		10 kΩ or higher
    VPA (A26-6) or VPA (A49-53) - Body ground
    		10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE ACCELERATOR PEDAL ROD ASSEMBLY