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

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DESCRIPTION

This ETCS (Electronic Throttle Control System) does not use a throttle cable.
The Accelerator Pedal Position (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.

A019803E02


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)
  1. Accelerator Pedal Position (APP) sensor
  1. ECM
P2122
VPA 0.4 V or less for 0.5 seconds or more when accelerator pedal fully released (1 trip detection logic)
  1. APP sensor
  1. Open in VCP1 circuit
  1. Open or ground short in VPA circuit
  1. ECM
P2123
VPA 4.8 V or more for 2.0 seconds or more
(1 trip detection logic)
  1. APP sensor
  1. Open in EPA circuit
  1. ECM
P2125
VPA2 fluctuates rapidly beyond upper and lower malfunction thresholds for 0.5 seconds or more (1 trip detection logic)
  1. APP sensor
  1. ECM
P2127
VPA2 1.2 V or less for 0.5 seconds or more when accelerator pedal fully released (1 trip detection logic)
  1. APP sensor
  1. Open in VCP2 circuit
  1. Open or ground short in VPA2 circuit
  1. ECM
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
  1. APP sensor
  1. Open in EPA2 circuit
  1. ECM
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
  1. Short between VPA and VPA2 circuits
  1. APP sensor
  1. ECM

HINT:
When any of these DTCs are set, check the APP sensor voltage by entering the following menus on the intelligent tester: Power train / Engine / Data List /Accelerator Position No. 1 and Accelerator Position No. 2

Trouble Areas
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 0.4 V
0 to 1.2 V
0 to 0.4 V
0 to 1.2 V
Open or ground short in VPA circuit
0 to 0.4 V
1.2 to 2.0 V
0 to 0.4 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:
  1. Accelerator pedal positions are expressed as voltages.
  1. AP denotes for Accelerator Pedal.


MONITOR DESCRIPTION

When either of the output voltages 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 sets a DTC.
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 set.
If the malfunction is not repaired successfully, a DTC is set 2 seconds after the engine is next started.

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 engine switch is then turned to off.

WIRING DIAGRAM


A105237E04


INSPECTION PROCEDURE

HINT:
  1. Read freeze frame data using the intelligent tester. Freeze frame data records the engine conditions 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. These DTCs relate to the Accelerator Pedal Position (APP) sensor.

1.READ VALUE USING INTELLIGENT TESTER (ACCELERATOR POSITION NO. 1 AND ACCELERATOR POSITION NO. 2)
FI07052E06

  1. Connect the intelligent tester to the DLC3.

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

  1. Enter the following menus: Power train / Engine / Data List / Accelerator Position No. 1 and Accelerator Position No. 2

  1. Read the value displayed on the tester.

    Standard voltage:
    Accelerator Pedal Operations
    		Accelerator Position No. 1
    (AP#1)
    		Accelerator Position No. 2
    (AP#2)
    Released
    		0.5 to 1.1 V
    		1.2 to 2.0 V
    Depressed
    		2.6 to 4.5 V
    		3.4 to 5.0 V



OK
Go to step 5
NG


2.CHECK HARNESS AND CONNECTOR (ACCELERATOR PEDAL POSITION SENSOR - ECM)
A107703E07

  1. Disconnect the A36 Accelerator Pedal Position (APP) sensor connector.

  1. Disconnect the A7 ECM connector.

  1. Measure the resistance.

    Standard resistance (Check for open):
    Tester Connection
    		Specified Condition
    VPA (A36-6) - VPA (A7-33)
    		Below 1 Ω
    EPA (A36-5) - EPA (A7-34)
    		Below 1 Ω
    VCPA (A36-4) - VCPA (A7-35)
    		Below 1 Ω
    VPA2 (A36-3) - VPA2 (A7-32)
    		Below 1 Ω
    EPA2 (A36-2) - EPA2 (A7-26)
    		Below 1 Ω
    VCP2 (A36-1) - VCP2 (A7-27)
    		Below 1 Ω

    Standard resistance (Check for short):
    Tester Connection
    		Specified Condition
    VPA (A36-6) or VPA (A7-33) - body ground
    		10 kΩ or higher
    EPA (A36-5) or EPA (A7-34) - body ground
    		10 kΩ or higher
    VCPA (A36-4) or VCPA (A7-35) - body ground
    		10 kΩ or higher
    VPA2 (A36-3) or VPA2 (A7-32) - body ground
    		10 kΩ or higher
    EPA2 (A36-2) or EPA2 (A7-26) - body ground
    		10 kΩ or higher
    VCP2 (A36-1) or VCP2 (A7-27) - body ground
    		10 kΩ or higher

  1. Reconnect the APP sensor connector.

  1. Reconnect the ECM connector.



NG
REPAIR OR REPLACE HARNESS AND CONNECTOR
OK


3.INSPECT ECM (VCPA AND VCP2 VOLTAGE)
A107704E02

  1. Disconnect the A36 APP sensor connector.

  1. Turn the engine switch on (IG).

  1. Measure the voltage between the terminals of the A7 ECM connector.

    Standard voltage:
    Tester Connection
    		Specified Condition
    VCPA (A7-35) - EPA (A7-34)
    		4.5 to 5.0 V
    VCP2 (A7-27) - EPA2 (A7-26)
    		4.5 to 5.0 V

  1. Reconnect the APP sensor connector.



NG
REPLACE ECM
OK


4.REPLACE ACCELERATOR PEDAL ROD ASSEMBLY

NEXT


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

  1. Connect the intelligent tester to the DLC3.

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

  1. Clear DTCs (Click here).

  1. Start the engine.

  1. Allow the engine to idle for 15 seconds.

  1. Enter the following menus: Power train / Engine / DTC.

  1. Read DTCs.

    Result:

    Display (DTC Output)
    		Proceed to
    P2120, P2122, P2123, P2125, P2127, P2128, and/or P2138
    		A
    No output
    		B



B
SYSTEM OK
A

REPLACE ECM