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 the accelerator position and a malfunction of the accelerator pedal position sensor.

In the accelerator pedal position sensor, the voltage applied to 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 engine control, and the VPA2 is a signal to indicate 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.

Dtc P2120 Throttle / Pedal Position Sensor / Switch D Circuit. 1VD-FTV ENGINE CONTROL. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

P2120
DTC Detection Drive Pattern	DTC Detection Condition	Trouble Area
Engine switch on (IG) Accelerator pedal fully released for 3 seconds Accelerator pedal depressed partway for 3 seconds Accelerator pedal fully depressed for 3 seconds	Condition (a) continues for 0.5 seconds: (1 trip detection logic) (a) VPA is below 0.4 V and VPA2 is more than 2.7 deg, or VPA is higher than 4.8 V.	Accelerator pedal position sensor Accelerator pedal assembly Accelerator pedal rod (arm) deformed ECM

P2122
DTC Detection Drive Pattern	DTC Detection Condition	Trouble Area
Engine switch on (IG) Accelerator pedal fully released for 3 seconds Accelerator pedal depressed partway for 3 seconds Accelerator pedal fully depressed for 3 seconds	Conditions (a) and (b) continue for 0.5 seconds: (1 trip detection logic) (a) VPA is below 0.4 V. (b) VPA2 is more than 2.7 deg.	Accelerator pedal position sensor Open in VCPA circuit VPA circuit open or shorted to ground Accelerator pedal assembly Accelerator pedal rod (arm) deformed ECM

P2123
DTC Detection Drive Pattern	DTC Detection Condition	Trouble Area
Engine switch on (IG) Accelerator pedal fully released for 3 seconds Accelerator pedal depressed partway for 3 seconds Accelerator pedal fully depressed for 3 seconds	Condition (a) continues for 2.0 seconds: (1 trip detection logic) (a) VPA is higher than 4.8 V.	Accelerator pedal position sensor Open in EPA circuit Accelerator pedal assembly Accelerator pedal rod (arm) deformed ECM

P2125
DTC Detection Drive Pattern	DTC Detection Condition	Trouble Area
Engine switch on (IG) Accelerator pedal fully released for 3 seconds Accelerator pedal depressed partway for 3 seconds Accelerator pedal fully depressed for 3 seconds	Condition (a) continues for 0.5 seconds: (1 trip detection logic) (a) VPA2 is below 1.2 V and VPA is more than 2.7 deg, or VPA2 is higher than 4.8 V and VPA is higher than 0.4 V but below 3.45 V.	Accelerator pedal position sensor Accelerator pedal assembly Accelerator pedal rod (arm) deformed ECM

P2127
DTC Detection Drive Pattern	DTC Detection Condition	Trouble Area
Engine switch on (IG) Accelerator pedal fully released for 3 seconds Accelerator pedal depressed partway for 3 seconds Accelerator pedal fully depressed for 3 seconds	Conditions (a) and (b) continue for 0.5 seconds: (1 trip detection logic) (a) VPA2 is below 1.2 V. (b) VPA1 is more than 2.7 deg.	Accelerator pedal position sensor Open in VCP2 circuit VPA2 circuit open or shorted to ground Accelerator pedal assembly Accelerator pedal rod (arm) deformed ECM

P2128
DTC Detection Drive Pattern	DTC Detection Condition	Trouble Area
Engine switch on (IG) Accelerator pedal fully released for 3 seconds Accelerator pedal depressed partway for 3 seconds Accelerator pedal fully depressed for 3 seconds	Conditions (a) and (b) continue for 2.0 seconds: (1 trip detection logic) (a) VPA2 is higher than 4.8 V. (b) VPA is higher than 0.4 V but below 3.45 V.	Accelerator pedal position sensor Open in EPA2 circuit Accelerator pedal assembly Accelerator pedal rod (arm) deformed ECM

P2138
DTC Detection Drive Pattern	DTC Detection Condition	Trouble Area
Engine switch on (IG) Accelerator pedal fully released for 3 seconds Accelerator pedal depressed partway for 3 seconds Accelerator pedal fully depressed for 3 seconds	Conditions (a) or (b) continue for 2.0 seconds: (1 trip detection logic) (a) The difference between VPA and VPA2 is less than 0.02 V. (b) VPA is below 0.4 V and VPA2 is below 1.2 V.	VPA and VPA2 circuits are short-circuited Accelerator pedal position sensor Accelerator pedal assembly Accelerator pedal rod (arm) deformed ECM

Related Data List
DTC No.	Data List
P2120 P2122 P2123 P2125 P2127 P2128 P2138	Accel Position Accel Sens. No.1 Volt % Accel Sens. No.2 Volt %

WIRING DIAGRAM

Dtc P2120 Throttle / Pedal Position Sensor / Switch D Circuit. 1VD-FTV ENGINE CONTROL. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

INSPECTION PROCEDURE

NOTICE:

After replacing the ECM, the new ECM needs registration () and initialization ().

After replacing the fuel supply pump assembly, the ECM needs initialization ().

After replacing an injector assembly, the ECM needs registration ().

HINT:

Read freeze frame data using the GTS. 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, and other data from the time the malfunction occurred.

1.READ VALUE USING GTS (ACCELERATOR PEDAL POSITION)

Dtc P2120 Throttle / Pedal Position Sensor / Switch D Circuit. 1VD-FTV ENGINE CONTROL. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

Connect the GTS to the DLC3.

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

Enter the following menus: Engine and ECT / Data List / Accel Sens. No.1 Volt % and Accel Sens. No.2 Volt %.

Read the values.

Standard:
Accelerator Pedal Accel Sens. No.1 Volt % Accel Sens. No.2 Volt %
Released 10 to 22% 24 to 40%
Depressed 52 to 90% 68 to 99%

Text in Illustration
*1	Accelerator Pedal Assembly
*a	Depressed
*b	Released

Result
Result	Proceed to
NG	A
OK	B

Go to step 7

A

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

Disconnect the accelerator pedal position sensor connector.

Disconnect the ECM connector.

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

Standard Resistance:

for LHD
Tester Connection	Condition	Specified Condition
A31-1 (VCP2) - A38-56 (VCP2)	Always	Below 1 Ω
A31-2 (EPA2) - A38-58 (EPA2)	Always	Below 1 Ω
A31-3 (VPA2) - A38-54 (VPA2)	Always	Below 1 Ω
A31-4 (VCPA) - A38-55 (VCPA)	Always	Below 1 Ω
A31-5 (EPA) - A38-57 (EPA)	Always	Below 1 Ω
A31-6 (VPA) - A38-53 (VPA)	Always	Below 1 Ω
A31-1 (VCP2) or A38-56 (VCP2) - Body ground	Always	10 kΩ or higher
A31-2 (EPA2) or A38-58 (EPA2) - Body ground	Always	10 kΩ or higher
A31-3 (VPA2) or A38-54 (VPA2) - Body ground	Always	10 kΩ or higher
A31-4 (VCPA) or A38-55 (VCPA) - Body ground	Always	10 kΩ or higher
A31-5 (EPA) or A38-57 (EPA) - Body ground	Always	10 kΩ or higher
A31-6 (VPA) or A38-53 (VPA) - Body ground	Always	10 kΩ or higher

Standard Resistance:

for RHD
Tester Connection	Condition	Specified Condition
A31-1 (VCP2) - A52-56 (VCP2)	Always	Below 1 Ω
A31-2 (EPA2) - A52-58 (EPA2)	Always	Below 1 Ω
A31-3 (VPA2) - A52-54 (VPA2)	Always	Below 1 Ω
A31-4 (VCPA) - A52-55 (VCPA)	Always	Below 1 Ω
A31-5 (EPA) - A52-57 (EPA)	Always	Below 1 Ω
A31-6 (VPA) - A52-53 (VPA)	Always	Below 1 Ω
A31-1 (VCP2) or A52-56 (VCP2) - Body ground	Always	10 kΩ or higher
A31-2 (EPA2) or A52-58 (EPA2) - Body ground	Always	10 kΩ or higher
A31-3 (VPA2) or A52-54 (VPA2) - Body ground	Always	10 kΩ or higher
A31-4 (VCPA) or A52-55 (VCPA) - Body ground	Always	10 kΩ or higher
A31-5 (EPA) or A52-57 (EPA) - Body ground	Always	10 kΩ or higher
A31-6 (VPA) or A52-53 (VPA) - Body ground	Always	10 kΩ or higher

Reconnect the accelerator pedal position sensor connector.

Reconnect the ECM connector.

Go to step 6

OK

3.INSPECT ECM TERMINAL VOLTAGE (VCPA AND VCP2 TERMINALS)

Disconnect the accelerator pedal position sensor connector.

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

Standard Voltage:
Tester Connection Switch Condition Specified 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

Text in Illustration
*a	Front view of wire harness connector (to Accelerator Pedal Position Sensor)

Reconnect the accelerator pedal position sensor connector.

Go to step 5

OK

4.REPLACE ACCELERATOR PEDAL ROD ASSEMBLY

Replace the accelerator pedal rod assembly ().

Go to step 7

5.REPLACE ECM

Replace the ECM ().

Go to step 7

6.REPAIR OR REPLACE HARNESS OR CONNECTOR

Repair or replace the harness or connector.

NEXT

7.CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

Connect the GTS to the DLC3.

Clear the DTCs ().

Turn the engine switch off and leave the vehicle for 30 seconds.

Turn the engine switch on (IG).

Fully release the accelerator pedal for 3 seconds or more, then depress it partway for 3 seconds or more, and then fully depress it for 3 seconds or more.

Confirm that the DTC is not output again.

END

1VD-FTV ENGINE CONTROL

Land Cruiser URJ200 URJ202 GRJ200 VDJ200

ECD SYSTEM w/ DPF

Accelerator Pedal	Accel Sens. No.1 Volt %	Accel Sens. No.2 Volt %
Released	10 to 22%	24 to 40%
Depressed	52 to 90%	68 to 99%

Tester Connection	Switch Condition	Specified 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