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Home >> Scion >> 2012 >> xD L4-1.8L (2ZR-FE) >> Repair and Diagnosis >> A L L Diagnostic Trouble Codes ( DTC ) >> Testing and Inspection >> P Code Charts >> P2121

P2121





2ZR-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P2121: Throttle / Pedal Position Sensor / Switch "D" Circuit Range / Performance
P2121 - Throttle / Pedal Position Sensor / Switch "D" Circuit Range / Performance

DESCRIPTION

HINT
- This DTC relates to the accelerator pedal position sensor.
- Refer to DTC P2120 P2120.





MONITOR DESCRIPTION

The accelerator pedal position sensor is mounted on the accelerator pedal assembly. The accelerator pedal position sensor has 2 sensor elements and 2 signal outputs: VPA and VPA2. VPA is used to detect the actual accelerator pedal angle (used for engine control) and VPA2 is used to detect malfunctions in VPA. When the difference between the output voltages of VPA and VPA2 deviates from the standard, the ECM determines that the accelerator pedal position sensor is malfunctioning. The ECM turns on the MIL and stores the DTC.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS

ALL (Case 1 and Case 2)





Case 2





TYPICAL MALFUNCTION THRESHOLDS

Case 1





Case 2





CONFIRMATION DRIVING PATTERN





1. Connect the Techstream to the DLC3.

2. Turn the ignition switch to ON and turn the Techstream on.

3. Clear DTCs (even if no DTCs are stored, perform the clear DTC operation).

4. Turn the ignition switch off and wait for at least 30 seconds.

5. Turn the ignition switch to ON and turn the Techstream on [A].

6. Wait for 5 seconds after turning the ignition switch to ON.

7. Operate the accelerator pedal in accordance with the following procedure [B].

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

b. Slowly depress the accelerator pedal until Accel Sens. No. 1 Volt % is approximately 30% and Accel Sens. No. 2 Volt % is approximately 46%, then slowly release the accelerator pedal.

8. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [C].

9. Read pending DTCs.

HINT
- If a pending DTC is output, the system is malfunctioning.
- If a pending DTC is not output, perform the following procedure.

10. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

11. Input the DTC: P2121.

12. Check the DTC judgment result.





HINT
- If the judgment result shows NORMAL, the system is normal.
- If the judgment result shows ABNORMAL, the system has a malfunction.
- If the judgment result shows INCOMPLETE or N/A, perform steps [B] and [C] again.

13. If the test result is INCOMPLETE or N/A and no pending DTC is output, perform a universal trip and check for permanent DTCs Reading and Clearing Diagnostic Trouble Codes.

HINT
- If a permanent DTC is output, the system is malfunctioning.
- If no permanent DTC is output, the system is normal.

FAIL-SAFE

The accelerator pedal position sensor has 2 (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 2 sensor circuits and switches to fail-safe mode. In fail-safe 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 P2120.

INSPECTION PROCEDURE

HINT
- This DTC relates to the accelerator pedal position sensor.
- Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. 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.

PROCEDURE

1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P2121)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

(e) Read DTCs.

Result





HINT
If any DTCs other than P2121 are output, troubleshoot those DTCs first.

B -- GO TO DTC CHART SFI System
A -- Continue to next step.

2. READ VALUE USING TECHSTREAM (ACCELERATOR POSITION SENSOR)





(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Enter the following menus: Powertrain / Engine and ECT / Data List / Accel Sensor Out No. 1 and Accel Sensor Out No. 2.

(e) Read the values displayed on the Techstream.

Standard Voltage:





Text in Illustration





NG -- REPLACE ACCELERATOR PEDAL ASSEMBLY

OK -- CHECK FOR INTERMITTENT PROBLEMS Check For Intermittent Problems

3. REPLACE ACCELERATOR PEDAL ASSEMBLY

(a) Replace the accelerator pedal assembly Removal.

NEXT -- Continue to next step.

4. CHECK WHETHER DTC OUTPUT RECURS (DTC P2121)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Clear DTCs Reading and Clearing Diagnostic Trouble Codes.

(e) Turn the ignition switch off and wait for at least 30 seconds.

(f) Turn the ignition switch to ON and turn the Techstream on.

(g) Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

(h) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

(i) Read the DTCs.

Result





B -- END

A -- REPLACE ECM Removal
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