LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Nissan-Datsun >> 2008 >> Quest Base >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System - DTCS P1211 Through P2A03 >> DTC P2138 App Sensor >> Diagnostic Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Diagnostic Procedure

  1. CHECK GROUND CONNECTIONS 
    1. Turn ignition switch OFF.
    2. Loosen and retighten three ground screws on the body. Refer to "GROUND INSPECTION ".
      Fig 1: Identifying Ground Screws On Body
      G04905801Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: GO TO 2.

    NG: Repair or replace ground connections.

  2. CHECK APP SENSOR 1 POWER SUPPLY CIRCUIT 
    1. Disconnect accelerator pedal position (APP) sensor harness connector.
    2. Turn ignition switch ON.
      Fig 2: Identifying Accelerator Pedal Position (APP) Sensor Harness Connector
      G04905676Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check voltage between APP sensor terminals 7 and ground with CONSULT-III or tester.

      Voltage: Approximately 5V 

    OK or NG 

    OK: GO TO 3.

    NG: Repair open circuit or short to ground or short to power in harness or connectors.

    Fig 3: Checking Voltage Between APP Sensor Terminal 7 And Ground
    G04905677Courtesy of NISSAN MOTOR CO., U.S.A.
  3. CHECK APP SENSOR 2 POWER SUPPLY CIRCUIT-I 

    Check voltage between APP sensor terminal 6 and ground with CONSULT-III or tester.

    Voltage: Approximately 5V 

    OK or NG 

    OK: GO TO  8.

    NG: GO TO 4.

    Fig 4: Checking Voltage Between APP Sensor Terminal 6 And Ground
    G04905789Courtesy of NISSAN MOTOR CO., U.S.A.
  4. CHECK APP SENSOR 2 POWER SUPPLY CIRCUIT-II 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Check harness continuity between APP sensor terminal 6 and ECM terminal 91.

      Refer to WIRING DIAGRAM .

      Continuity should exist. 

    OK or NG 

    OK: GO TO 5.

    NG: Repair open circuit.

  5. CHECK APP SENSOR 2 POWER SUPPLY CIRCUIT-III 

    Check harness for short to power and short to ground, between the following terminals.

    ECM CONNECTOR TERMINAL REFERENCE WIRING DIAGRAM

    ECM terminal Sensor terminal
    91  APP sensor terminal 6
    47  Electric throttle control actuator terminal 1

    OK or NG 

    OK: GO TO 6.

    NG: Repair short to ground or short to power in harness or connectors.

  6. CHECK THROTTLE POSITION SENSOR 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO  12.

    NG: GO TO 7.

  7. REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR 
    1. Replace electric throttle control actuator.
    2. Perform "THROTTLE VALVE CLOSED POSITION LEARNING ".
    3. Perform "IDLE AIR VOLUME LEARNING ".

      : INSPECTION END 

  8. CHECK APP SENSOR GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Check harness continuity between APP sensor terminals 1 and ECM terminal 82, APP sensor terminal 3 and ECM terminal 83.

      Refer to WIRING DIAGRAM .

      Continuity should exist. 

    4. Also check harness for short to ground and short to power.

    OK or NG 

    OK: GO TO 9.

    NG: Repair open circuit or short to ground or short to power in harness or connectors.

  9. CHECK APP SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Check harness continuity between ECM terminal 106 and APP sensor terminal 2, ECM terminal 98 and APP sensor terminal 5.

      Refer to WIRING DIAGRAM .

      Continuity should exist. 

    2. Also check harness for short to ground and short to power.

    OK or NG 

    OK: GO TO 10.

    NG: Repair open circuit or short to ground or short to power in harness or connectors.

  10. CHECK APP SENSOR 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO  12.

    NG: GO TO 11.

  11. REPLACE ACCELERATOR PEDAL ASSEMBLY 
    1. Replace accelerator pedal assembly.
    2. Perform "ACCELERATOR PEDAL RELEASED POSITION LEARNING ".
    3. Perform "THROTTLE VALVE CLOSED POSITION LEARNING ".
    4. Perform "IDLE AIR VOLUME LEARNING ".

      : INSPECTION END 

  12. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    : INSPECTION END