READ VALUE USING INTELLIGENT TESTER (ACCELERATOR POSITION NO. 1 AND ACCELERATOR POSITION NO. 2)
CHECK HARNESS AND CONNECTOR (ACCELERATOR PEDAL POSITION SENSOR - ECM)
INSPECT ECM (VCPA AND VCP2 VOLTAGE)
REPLACE ACCELERATOR PEDAL ROD 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 |
- HINT:
- These DTCs relate to the Accelerator Pedal Position (APP) sensor.
- This ETCS (Electronic Throttle Control System) does not use a throttle cable.
DESCRIPTION
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 V and 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 No. | DTC Detection Condition | Trouble Area |
P2120 | VPA fluctuates rapidly beyond upper and lower malfunction thresholds for 0.5 seconds or more (1 trip detection logic) |
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P2122 | VPA 0.4 V or less for 0.5 seconds or more when accelerator pedal fully released (1 trip detection logic) |
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P2123 | VPA 4.8 V or more for 2.0 seconds or more (1 trip detection logic) |
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P2125 | VPA2 fluctuates rapidly beyond upper and lower malfunction thresholds for 0.5 seconds or more (1 trip detection logic) |
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P2127 | VPA2 1.2 V or less for 0.5 seconds or more when accelerator pedal fully released (1 trip detection logic) |
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P2128 | Conditions (a) and (b) continue for 2.0 seconds or more (1 trip detection logic): (a) VPA2 4.8 V or more (b) VPA between 0.4 V and 3.45 V |
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P2138 | Condition (a) or (b) continues for 2.0 seconds or more (1 trip detection logic): (a) Difference between VPA and VPA2 0.02 V or less (b) VPA 0.4 V or less and VPA2 1.2 V or less |
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- HINT:
- When any of these DTCs are set, check the APP sensor voltage by selecting the following menu items on the intelligent tester: Powertrain / Engine and ECT / Data List / Accelerator Position No. 1 and Accelerator Position No. 2.
Trouble Area | Accelerator Position No. 1 When AP Released | Accelerator Position No. 2 When AP Released | Accelerator Position No. 1 When AP Depressed | Accelerator Position No. 2 When AP Depressed |
VCP circuit open | 0 to 0.2 V | 0 to 0.2 V | 0 to 0.2 V | 0 to 0.2 V |
Open or ground short in VPA circuit | 0 to 0.2 V | 1.2 to 2.0 V | 0 to 0.2 V | 3.4 to 5.0 V |
Open or ground short in VPA2 circuit | 0.5 to 1.1 V | 0 to 0.2 V | 2.6 to 4.5 V | 0 to 0.2 V |
EPA circuit open | 4.5 to 5.0 V | 4.5 to 5.0 V | 4.5 to 5.0 V | 4.5 to 5.0 V |
Normal condition | 0.5 to 1.1 V | 1.2 to 2.0 V | 2.6 to 4.5 V | 3.4 to 5.0 V |
- HINT:
- Accelerator pedal positions are expressed as voltages.
- AP stands for Accelerator Pedal.
FAIL-SAFE
When any of DTCs P2120, P2121, P2122, P2123, P2125, P2127, P2128 and P2138 are set, 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 ignition switch is turned off.WIRING DIAGRAM

INSPECTION PROCEDURE
- HINT:
- 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 be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air-fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction (RAV4_ACA30 RM000000PDS09FX.html).
1.READ VALUE USING INTELLIGENT TESTER (ACCELERATOR POSITION NO. 1 AND ACCELERATOR POSITION NO. 2) |
Connect the intelligent tester to the DLC3.
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Turn the ignition switch to the ON position and turn the tester on.
Select the following menu items: Powertrain / Engine and ECT / Data List / Accelerator Position No. 1 and Accelerator Position No. 2.
Read the value displayed on the tester.
- Standard voltage:
Accelerator Pedal Operation Accelerator Position No. 1 Accelerator Position No. 2 Released → Depressed → Released 0.5 to 4.5 V 1.2 to 5.0 V Difference between Accelerator Position No. 1 and Accelerator Position No. 2 is greater than 0.02 V Difference between Accelerator Position No. 1 and Accelerator Position No. 2 is greater than 0.02 V
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NG | |
2.CHECK HARNESS AND CONNECTOR (ACCELERATOR PEDAL POSITION SENSOR - ECM) |
Disconnect the Accelerator Pedal Position (APP) sensor connector.
Disconnect the ECM connector.
Measure the resistance.
- Standard resistance (Check for open):
Tester Connection Specified Condition VPA (A6-6) - VPA (A12-55) Below 1 Ω EPA (A6-5) - EPA (A12-59) VCPA (A6-4) - VCPA (A12-57) VPA2 (A6-3) - VPA2 (A12-56) EPA2 (A6-2) - EPA2 (A12-60) VCP2 (A6-1) - VCP2 (A12-58)
- Standard resistance (Check for short):
Tester Connection Specified Condition VPA (A6-6) or VPA (A12-55) - Body ground 10 kΩ or higher EPA (A6-5) or EPA (A12-59) - Body ground VCPA (A6-4) or VCPA (A12-57) - Body ground VPA2 (A6-3) or VPA2 (A12-56) - Body ground EPA2 (A6-2) or EPA2 (A12-60) - Body ground VCP2 (A6-1) or VCP2 (A12-58) - Body ground
Reconnect the APP sensor connector.
Reconnect the ECM connector.
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OK | |
3.INSPECT ECM (VCPA AND VCP2 VOLTAGE) |
Disconnect the APP sensor connector.
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Turn the ignition switch to the ON position.
Measure the voltage between the terminals of the A3 APP sensor connector.
- Standard voltage:
Tester Connection Specified Condition VCPA (A6-4) - EPA (A6-5) 4.5 to 5.5 V VCP2 (A6-1) - EPA2 (A6-2)
Reconnect the APP sensor connector.
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OK | |
4.REPLACE ACCELERATOR PEDAL ROD ASSEMBLY |
NEXT | |
5.CHECK WHETHER DTC OUTPUT RECURS (ACCELERATOR PEDAL POSITION SENSOR DTCS) |
Connect the intelligent tester to the DLC3.
Turn the ignition switch to the ON position and turn the tester on.
Clear DTCs (RAV4_ACA30 RM000000PDK0WDX.html).
Start the engine.
Allow the engine to idle for 15 seconds.
Select the following menu items: Powertrain / Engine and ECT / DTC.
Read DTCs.
- Result:
Display (DTC Output) Proceed to P2120, P2122, P2123, P2125, P2127, P2128, and/or P2138 A No output B
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A | ||
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