Brand:

Toyota

Model Name:

4Runner GRN210 215 UZN210 215

Manual:

Repair Manual

Section:

1Gr-Fe Engine Control System

Title:

Sfi System

  1. Description

  2. Monitor description

  3. Monitor strategy

  4. Typical enabling conditions

  5. Typical malfunction thresholds

  6. Fail-safe

  7. Wiring diagram

  8. Inspection procedure

  9. Read value of intelligent tester (accel pos #1 and accel pos #2)

  10. Check harness and connector (accelerator pedal position sensor - ecm)

  11. Inspect ecm (vcpa and vcp2 voltage)

  12. Replace accelerator pedal rod assembly

  13. 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.

DESCRIPTION

HINT:
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.

Accelerator Pedal Position (APP) sensor 4Runner


DTC No.
DTC Detection Conditions
Trouble Areas
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
  2. ECM
P2122
VPA 0.4 V or less for 0.5 seconds or more when accelerator pedal is fully released (1 trip detection logic)
  1. APP sensor
  2. Open in VCP1 circuit
  3. Open or ground short in VPA circuit
  4. ECM
P2123
VPA 4.8 V or more for 2.0 seconds or more (1 trip detection logic)
  1. APP sensor
  2. Open in EPA circuit
  3. ECM
P2125
VPA2 fluctuates rapidly beyond upper and lower malfunction thresholds for 0.5 seconds or more (1 trip detection logic)
  1. APP sensor
  2. ECM
P2127
VPA2 is 1.2 V or less for 0.5 seconds or more when accelerator pedal is fully released (1 trip detection logic)
  1. APP sensor
  2. Open in VCP2 circuit
  3. Open or ground short in VPA2 circuit
  4. ECM
P2128
Conditions (a) and (b) continue for 2.0 seconds or more (1 trip detection logic):
(a) VPA2 is 4.8 V or more
(b) VPA between 0.4 V and 3.45 V
  1. APP sensor
  2. Open in EPA2 circuit
  3. ECM
P2138
Condition (a) or (b) continues for 2.0 seconds or more (1 trip detection logic):
(a) 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
  1. Short between VPA and VPA2 circuits
  2. APP sensor
  3. ECM

HINT:
When any of these DTCs are set, check the APP sensor voltage by selecting the following menu items on the intelligent tester: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / ACCEL POS #1 and ACCEL POS #2.

Trouble Areas
ACCEL POS #1 When AP Released
ACCEL POS #2 When AP Released
ACCEL POS #1 When AP Depressed
ACCEL POS #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:
  1. Accelerator pedal positions are expressed as voltages.
  2. AP denotes for Accelerator Pedal.

MONITOR DESCRIPTION

When either of the voltage outputs of VPA or VPA2 deviates from the standard range, or the difference between the voltage outputs 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:
  1. When the voltage output of VPA drops below 0.2 V for more than 0.5 seconds when the accelerator pedal is fully depressed, DTC P2122 is set.
  2. If the malfunction is not repaired successfully, a DTC is set 2 seconds after the engine is next started.

MONITOR STRATEGY


Related DTCs
P2120: Accelerator position sensor 1 (VPA) range check (Fluttering)
P2122: Accelerator position sensor 1 (VPA) range check (Low voltage)
P2123: Accelerator position sensor 1 (VPA) range check (High voltage)
P2125: Accelerator position sensor 2 (VPA2) range check (Fluttering)
P2127: Accelerator position sensor 2 (VPA2) range check (Low voltage)
P2128: Accelerator position sensor 2 (VPA2) range check (High voltage)
P2138: Accelerator position sensor correlation range check
Required Sensors / Components (Main)
Accelerator position sensor
Required Sensors / Components (Related)
-
Frequency of Operation
Continuous
Duration
2 seconds
MIL Operation
Immediate
Sequence Operation
None

TYPICAL ENABLING CONDITIONS


The monitor will run whenever these DTCs are not present
None
Ignition switch
ON
Throttle control motor power
ON

TYPICAL MALFUNCTION THRESHOLDS


P2120:
Either of the following conditions is met
Condition 1 or 2
1. VPA voltage when VPA2 is 0.04 V or more
0.4 V or less
2. VPA voltage
4.8 or more

P2122:
VPA1 voltage when VPA2 is 0.04 V or more
0.4 V or less

P2123:
VPA1 voltage
4.8 V or more

P2125:
Either of the following conditions is met
Condition 1 or 2
1. VPA2 voltage when VPA is 0.04 V or more
1.2 V or less
2. VPA2 voltage when VPA is 0.4 to 3.45 V
4.8 V or more

P2127:
VPA2 voltage when VPA1 is 0.04 V or more
1.2 V or less

P2128:
VPA2 voltage when VPA1 is 0.4 to 3.45 V
4.8 V or more

P2138:
Either of the following conditions is met:
Condition 1 or 2
1. Difference between VPA 1 and VPA2 voltage
0.02 V or less
2. Both of the following conditions are met:
Condition (a) and (b)
(a) VPA1 voltage
0.4 V or less
(b) VPA2 voltage
1.2 V or less

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 circuit 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


Sfi System - P0171 4Runner


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.
1.READ VALUE OF INTELLIGENT TESTER (ACCEL POS #1 AND ACCEL POS #2)
  1. Connect the intelligent tester to the DLC3. 4Runner

  2. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch on and turn the tester ON.

  1. Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / ACCEL POS #1 and ACCEL POS #2.

  1. Read the values displayed on the tester.

    Standard voltage:
    Accelerator Pedal Operations
    		ACCEL POS #1 (AP#1)
    		ACCEL POS #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


OKnext
Go to step 5
NG
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2.CHECK HARNESS AND CONNECTOR (ACCELERATOR PEDAL POSITION SENSOR - ECM)
  1. Disconnect the A24 Accelerator Pedal Position (APP) sensor connector. 4Runner

  2. Disconnect the A24 Accelerator Pedal Position (APP) sensor connector.

  1. Disconnect the E8 ECM connector.

  1. Measure the resistance.

    Standard resistance (Check for open):
    Tester Connections
    		Specified Conditions
    VPA (A24-6) - VPA (E8-18)
    		Below 1 Ω
    EPA (A24-5) - EPA (E8-20)
    		Below 1 Ω
    VCPA (A24-4) - VCPA (E8-26)
    		Below 1 Ω
    VPA2 (A24-3) - VPA2 (E8-19)
    		Below 1 Ω
    EPA2 (A24-2) - EPA2 (E8-21)
    		Below 1 Ω
    VCP2 (A24-1) - VCP2 (E8-27)
    		Below 1 Ω
    Standard resistance (Check for short):
    Tester Connections
    		Specified Conditions
    VPA (A24-6) or VPA (E8-18) - Body ground
    		10 kΩ or higher
    EPA (A24-5) or EPA (E8-20) - Body ground
    		10 kΩ or higher
    VCPA (A24-4) or VCPA (E8-26) - Body ground
    		10 kΩ or higher
    VPA2 (A24-3) or VPA2 (E8-19) - Body ground
    		10 kΩ or higher
    EPA2 (A24-2) or EPA2 (E8-21) - Body ground
    		10 kΩ or higher
    VCP2 (A24-1) or VCP2 (E8-27) - Body ground
    		10 kΩ or higher

  1. Reconnect the APP sensor connector.

  1. Reconnect the ECM connector.



NGnext
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
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3.INSPECT ECM (VCPA AND VCP2 VOLTAGE)
  1. Disconnect the A24 APP sensor connector. 4Runner

  2. Disconnect the A24 APP sensor connector.

  1. Turn the ignition switch on.

  1. Measure the voltage between the terminals of the E8 ECM connector.

    Standard voltage:
    Tester Connections
    		Specified Conditions
    VCPA (E8-26) - EPA (E8-20)
    		4.5 to 5.0 V
    VCP2 (E8-27) - EPA2 (E8-21)
    		4.5 to 5.0 V

  1. Reconnect the APP sensor connector.



NGnext
REPLACE ECM
OK
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4.REPLACE ACCELERATOR PEDAL ROD ASSEMBLY

  1. Replace the accelerator pedal rod assembly (Click here).


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

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch on and turn the tester on.

  1. Clear DTCs (Click here).

  1. Start the engine.

  1. Allow the engine to idle for 15 seconds.

  1. Select the following menu items on the tester: DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES.

  1. Read DTCs.

    Result:

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


Bnext
SYSTEM OK
A
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REPLACE ECM