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
Refer to DTC P2120 P2120.
HINT
This DTC relates to the Accelerator Pedal Position (APP) sensor.
MONITOR DESCRIPTION
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 the DTC is set.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
TYPICAL MALFUNCTION THRESHOLDS
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. Fully depress and release the accelerator pedal [B].
7. Check that 20 seconds or more have elapsed since the DTCs were cleared.
8. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [C].
9. Read the DTCs.
HINT
- If a DTC is output, the system is malfunctioning.
- If a 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 UNKNOWN, perform steps [B] and [C] again.
13. If the test result is INCOMPLETE or UNKNOWN and no 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 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 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. Freeze frame data records 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.
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 the DTCs.
Result
HINT
If any DTCs other than P2121 are output, troubleshoot those DTCs first.
B -- GO TO DTC CHART Engine Control System - 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 ROD ASSEMBLY
OK -- CHECK FOR INTERMITTENT PROBLEMS Check for Intermittent Problems
3. REPLACE ACCELERATOR PEDAL ROD ASSEMBLY
(a) Replace the accelerator pedal rod assembly Removal.
NEXT -- Continue to next step.
4. CHECK WHETHER DTC OUTPUT RECURS (ACCELERATOR PEDAL POSITION SENSOR DTCS)
(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.
(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