P2123

2011 Infiniti M56 V8-5.6L (VK56VD)SECTION P2123

P2122, P2123 APP SENSOR





DTC Logic

DTC DETECTION LOGIC

NOTE:
If DTC P2122 or P2123 is displayed with DTC P0643, perform the trouble diagnosis for DTC P0643. P0643.






DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is 8 V or more at idle.
- GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine and let it idle for 1 second.
2. Check DTC.
Is DTC detected?
YES - Proceed to SEE Diagnosis Procedure.
NO - INSPECTION END




Diagnosis Procedure
1.CHECK ACCELERATOR PEDAL POSITION SENSOR 1 POWER SUPPLY CIRCUIT
1. Disconnect accelerator pedal position (APP) sensor harness connector.
2. Turn ignition switch ON.
3. Check the voltage between APP sensor harness connector and ground.





Is the inspection result normal?
YES - GO TO 3.
NO - GO TO 2.
2.DETECT MALFUNCTIONING PART
Check the following.
- Harness for open or short between ECM and APP sensor
- Loose or poor connection for each connector and harness
- Repair open circuit, short to ground or short to power in harness or connectors.
3.CHECK APP SENSOR 1 GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between APP sensor harness connector and ECM harness connector.





4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES - GO TO 5.
NO - GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
- Harness for open or short between ECM and APP sensor
- Loose or poor connection for each connector and harness
- Repair open circuit, short to ground or short to power in harness or connectors.
5.CHECK APP SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check the continuity between APP sensor harness connector and ECM harness connector.





2. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES - GO TO 7.
NO - GO TO 6.
6.DETECT MALFUNCTIONING PART
Check the following.
- Loose or poor connection for each connector and harness
- Harness for open or short between ECM and APP sensor
- Repair open circuit, short to ground or short to power in harness or connectors.
7.CHECK APP SENSOR
SEE Component Inspection (Accelerator Pedal Position Sensor).
Is the inspection result normal?
YES - GO TO 9.
NO - GO TO 8.
8.REPLACE ACCELERATOR PEDAL ASSEMBLY
Replace accelerator pedal assembly.
Removal And Installation Without Distance Control Assist System(Without distance control assist system). Removal And Installation With Distance Control Assist System (With distance control assist system).
- INSPECTION END
9.CHECK INTERMITTENT INCIDENT
Intermittent Incident.
- INSPECTION END




Component Inspection (Accelerator Pedal Position Sensor)
1.CHECK ACCELERATOR PEDAL POSITION SENSOR
1. Turn ignition switch OFF.
2. Reconnect all harness connectors disconnected.
3. Turn ignition switch ON.
4. Check the voltage ECM harness connector terminals under the following conditions.





Is the inspection result normal?
YES - INSPECTION END
NO - GO TO 2.
2.REPLACE ACCELERATOR PEDAL ASSEMBLY
Replace accelerator pedal assembly. Removal And Installation Without Distance Control Assist System(Without distance control assist system). Removal And Installation With Distance Control Assist System (With distance control assist system).
- INSPECTION END
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.