Dtc P2120 Throttle / Pedal Position Sensor / Switch D Circuit

Land Cruiser URJ200 URJ202 GRJ200 VDJ200 - 3UR-FE ENGINE CONTROL

DESCRIPTION

MONITOR DESCRIPTION

FAIL-SAFE

WIRING DIAGRAM

INSPECTION PROCEDURE

READ VALUE USING INTELLIGENT TESTER (ACCELERATOR POSITION SENSOR)

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

CHECK ECM (VCPA AND VCP2 VOLTAGE)

REPLACE ACCELERATOR PEDAL ASSEMBLY

CHECK WHETHER DTC OUTPUT RECURS (ACCELERATOR PEDAL POSITION SENSOR DTCS)

DTC P2120 Throttle / Pedal Position Sensor / Switch "D" Circuit

DTC P2122 Throttle / Pedal Position Sensor / Switch "D" Circuit Low Input

DTC P2123 Throttle / Pedal Position Sensor / Switch "D" Circuit High Input

DTC P2125 Throttle / Pedal Position Sensor / Switch "E" Circuit

DTC P2127 Throttle / Pedal Position Sensor / Switch "E" Circuit Low Input

DTC P2128 Throttle / Pedal Position Sensor / Switch "E" Circuit High Input

DTC P2138 Throttle / Pedal Position Sensor / Switch "D" / "E" Voltage Correlation

DESCRIPTION

  • HINT:
  • This ETCS (Electronic Throttle Control System) does not use a throttle cable.
  • The APP sensor is mounted on 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 0.5 V and 4.5 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 APP 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.

Dtc P2120 Throttle / Pedal Position Sensor / Switch D Circuit. 3UR-FE ENGINE CONTROL. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

DTC CodeDTC Detection ConditionTrouble Area
P2120VPA fluctuates rapidly beyond the upper and lower malfunction thresholds for 0.5 seconds or more (1 trip detection logic).
APP sensor
ECM
P2122VPA is 0.4 V or less for 0.5 seconds or more when the accelerator pedal is fully released (1 trip detection logic).
APP sensor
Open in VCP1 circuit
Open or ground short in VPA circuit
ECM
P2123VPA is 4.8 V or higher for 2.0 seconds or more (1 trip detection logic).
APP sensor
Open in EPA circuit
ECM
P2125VPA2 fluctuates rapidly beyond the upper and lower malfunction thresholds for 0.5 seconds or more (1 trip detection logic).
APP sensor
ECM
P2127VPA2 is 1.2 V or less for 0.5 seconds or more when the accelerator pedal is fully released (1 trip detection logic).
APP sensor
Open in VCP2 circuit
Open or ground short in VPA2 circuit
ECM
P2128Conditions (a) and (b) continue for 2.0 seconds or more (1 trip detection logic):
(a) VPA2 is 4.8 V or higher.
(b) VPA is between 0.4 V and 3.45 V.
APP sensor
Open in EPA2 circuit
ECM
P2138Condition (a) or (b) continues for 2.0 seconds or more (1 trip detection logic):
(a) The difference between VPA and VPA2 is 0.02 V or less.
(b) VPA is 0.4 V or less and VPA2 is 1.2 V or less.
Short between VPA and VPA2 circuits
APP sensor
ECM
  • HINT:
  • When any of these DTCs is output, check the APP sensor voltage by entering the following menus: Powertrain / Engine and ECT / Data List / ETCS / Accel Sensor Out No. 1 and Accel Sensor Out No. 2.
Trouble AreaAccel Sensor Out No. 1
When AP Released		Accel Sensor Out No. 2
When AP Released		Accel Sensor Out No. 1
When AP Depressed		Accel Sensor Out No. 2
When AP Depressed
VCP circuit open0 to 0.2 V0 to 0.2 V0 to 0.2 V0 to 0.2 V
Open or ground short in VPA circuit0 to 0.2 V1.2 to 2.0 V0 to 0.2 V3.4 to 4.75 V
Open or ground short in VPA2 circuit0.5 to 1.1 V0 to 0.2 V2.6 to 4.5 V0 to 0.2 V
EPA circuit open4.5 to 4.98 V 4.5 to 4.98 V4.5 to 4.98 V4.5 to 4.98 V
Normal condition0.5 to 1.1 V 1.2 to 2.0 V2.6 to 4.5 V3.4 to 4.75 V
  • HINT:
Accelerator pedal positions are expressed as voltages.
AP stands for Accelerator Pedal.

MONITOR DESCRIPTION

When either output voltage of VPA or VPA2 deviates from the standard range, or the difference between the output voltages of the 2 sensor circuits is less than the threshold, the ECM determines that there is a malfunction in the APP sensor. The ECM then illuminates the MIL and stores DTC(s).


Example:


When the output voltage of VPA drops below 0.4 V for more than 0.5 seconds when the accelerator pedal is fully depressed, DTC P2122 is stored.


If the malfunction is not repaired successfully, a DTC is stored 2 seconds after the engine is next started.


FAIL-SAFE

When any of DTCs P2120, P2121, P2122, P2123, P2125, P2127, P2128 and P2138 is stored, the ECM enters fail-safe mode. If either of the 2 sensor circuits malfunctions, the ECM uses the remaining circuit to calculate the accelerator pedal position to allow the vehicle to continue driving. If both of the circuits malfunction, the ECM regards the accelerator pedal as being released. As a result, the throttle valve is closed and the engine idles.


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


WIRING DIAGRAM

Dtc P2120 Throttle / Pedal Position Sensor / Switch D Circuit. 3UR-FE ENGINE CONTROL. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

INSPECTION PROCEDURE

  • HINT:
These DTCs relate to the Accelerator Pedal Position (APP) sensor.
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.
1.READ VALUE USING INTELLIGENT TESTER (ACCELERATOR POSITION SENSOR)
Dtc P2120 Throttle / Pedal Position Sensor / Switch D Circuit. 3UR-FE ENGINE CONTROL. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

Connect the intelligent tester to the DLC3.

Turn the engine switch on (IG) and turn the tester on.

Enter the following menus: Powertrain / Engine and ECT / Data List / ETCS / Accel Sensor Out No. 1 and Accel Sensor Out No. 2.

Read the value displayed on the tester.

  • Standard Voltage:
  • Accelerator Pedal OperationAccel Sensor Out No. 1Accel Sensor Out No. 2
    Released → Depressed → Released0.5 to 4.5 V1.2 to 4.75 V
    Difference between Accel Sensor Out No. 1 and Accel Sensor Out No. 2 is higher than 0.02 V Difference between Accel Sensor Out No. 1 and Accel Sensor Out No. 2 is higher than 0.02 V
Result
ResultProceed to
NGA
OKB
B
Go to step 5
A
2.CHECK HARNESS AND CONNECTOR (ACCELERATOR PEDAL POSITION SENSOR - ECM)

Disconnect the A31 accelerator pedal position (APP) sensor connector.

Disconnect the A38 ECM connector.

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

  • Standard Resistance:
  • Tester ConnectionConditionSpecified Condition
    A31-6 (VPA) - A38-55 (VPA)AlwaysBelow 1 Ω
    A31-5 (EPA) - A38-58 (EPA)AlwaysBelow 1 Ω
    A31-4 (VCPA) - A38-57 (VCPA)AlwaysBelow 1 Ω
    A31-3 (VPA2) - A38-56 (VPA2)AlwaysBelow 1 Ω
    A31-2 (EPA2) - A38-60 (EPA2)AlwaysBelow 1 Ω
    A31-1 (VCP2) - A38-59 (VCP2)AlwaysBelow 1 Ω
    A31-6 (VPA) or A38-55 (VPA) - body groundAlways10 kΩ or higher
    A31-5 (EPA) or A38-58 (EPA) - body groundAlways10 kΩ or higher
    A31-4 (VCPA) or A38-57 (VCPA) - body groundAlways10 kΩ or higher
    A31-3 (VPA2) or A38-56 (VPA2) - body groundAlways10 kΩ or higher
    A31-2 (EPA2) or A38-60 (EPA2) - body groundAlways10 kΩ or higher
    A31-1 (VCP2) or A38-59 (VCP2) - body groundAlways10 kΩ or higher
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
3.CHECK ECM (VCPA AND VCP2 VOLTAGE)
Dtc P2120 Throttle / Pedal Position Sensor / Switch D Circuit. 3UR-FE ENGINE CONTROL. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

Disconnect the A31 APP sensor connector.

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

  • Standard Voltage:
  • Tester ConnectionSwitch ConditionSpecified Condition
    A31-4 (VCPA) - A31-5 (EPA)Engine switch on (IG)4.5 to 5.5 V
    A31-1 (VCP2) - A31-2 (EPA2)Engine switch on (IG)4.5 to 5.5 V
NG
REPLACE ECM ()
OK
4.REPLACE ACCELERATOR PEDAL ASSEMBLY

Replace the accelerator pedal assembly ().

NEXT
5.CHECK WHETHER DTC OUTPUT RECURS (ACCELERATOR PEDAL POSITION SENSOR DTCS)

Connect the intelligent tester to the DLC3.

Turn the engine switch on (IG) and turn the tester on.

Clear DTCs ().

Start the engine.

Allow the engine to idle for 15 seconds.

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

Read DTCs.

Result
ResultProceed to
P2120, P2122, P2123, P2125, P2127, P2128, and/or P2138 are outputA
No DTC is outputB
B
SYSTEM OK
A
REPLACE ECM ()