Brand:

Toyota

Model Name:

Yaris NCP90 91 92 93

Manual:

Repair Manual

Section:

1Nz-Fe Engine Control System

Title:

Sfi System

  1. Description

  2. Fail-safe

  3. Wiring diagram

  4. Inspection procedure

  5. Check any other dtcs output (in addition to dtc p2121)

  6. Read value using intelligent tester (accelerator position no. 1 and accelerator position no. 2)

  7. Replace accelerator pedal assembly

  8. Check whether dtc output recurs (dtc p2121)

DTC P2121 Throttle / Pedal Position Sensor / Switch "D" Circuit Range / Performance


​

DESCRIPTION

Refer to DTC P2120 (Click here).

DTC No.
DTC Detection Conditions
Trouble Areas
P2121
Either of following conditions 1 or 2 met for 0.5 seconds (1 trip detection logic)
  1. Difference between VPA and VPA2 is less than 0.4 V, or more than 1.2 V. (learned value of accelerator off position)
  2. Difference between VPA and VPA2 is greater than or equal to the specified value.
  1. Accelerator Pedal Position (APP) sensor
  2. ECM

FAIL-SAFE

The APP sensor has two (main and sub) sensor circuits. If a malfunction occurs in either of the sensor circuits, the ECM detects the abnormal signal voltage difference between the two sensor circuits and switches to limp mode. In limp mode, the functioning circuit is used to calculate the accelerator pedal opening angle to allow the vehicle to continue driving. If both circuits malfunction, the ECM regards the opening angle of the accelerator pedal as being fully closed. In this case, the throttle valve remains closed as if the engine is idling. If a pass condition is detected and then the ignition switch is turned off, the fail-safe operation stops and the system returns to a normal condition.

WIRING DIAGRAM

Refer to DTC P2120 (Click here).

INSPECTION PROCEDURE

HINT:
Read freeze frame data using an intelligent tester. Freeze frame data record 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.CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P2121)

  1. Connect an intelligent tester to the DLC3.

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

  1. Select the following menu items: Powertrain / Engine and ECT / DTC.

  1. Read DTCs.

    Result:
    Display (DTC Output)
    		Proceed To
    P2121
    		A
    P2121 and other DTCs
    		B
    HINT:
    If any DTCs other than P2121 are output, troubleshoot those DTCs first.


Bnext
GO TO DTC CHART (Click here)
A
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2.READ VALUE USING INTELLIGENT TESTER (ACCELERATOR POSITION NO. 1 AND ACCELERATOR POSITION NO. 2)
Connect an intelligent tester to the DLC3. Yaris

  1. Connect an intelligent tester to the DLC3.

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

  1. Select the following menu items: Powertrain / Engine and ECT / Data List / Accelerator Position No. 1 and Accelerator Position No. 2.

  1. Read the values displayed on the tester.

    Standard voltage:
    Accelerator Pedal Operations
    		Accelerator Position No. 1
    		Accelerator Position No. 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
CHECK FOR INTERMITTENT PROBLEMS (Click here)
NG
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3.REPLACE ACCELERATOR PEDAL ASSEMBLY
Click here

NEXT
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4.CHECK WHETHER DTC OUTPUT RECURS (DTC P2121)

  1. Connect an intelligent tester to the DLC3.

  1. Turn the ignition switch to 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: Powertrain / Engine and ECT / DTC.

  1. Read DTCs.

    Result:
    Display (DTC Output)
    		Proceed To
    P2121
    		A
    No output
    		B


Bnext
SYSTEM OK
A
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REPLACE ECM (Click here)