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Home >> Nissan-Datsun >> 2005 >> Sentra SE-R >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 2 (Engine Control System (QG18DE)) >> DTC P2138: App Sensor >> Diagnostic Procedure
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Diagnostic Procedure

WARNING: This page is about a different variant/trim than selected.
  1. CHECK GROUND CONNECTIONS 
    1. Turn ignition switch OFF.
    2. Loosen and retighten two ground screws on the body. Refer to "GROUND INSPECTION ".
      Fig 1: Identifying ECM Ground Screws On Body
      G02450490Courtesy 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: Locating Accelerator Pedal Position (APP) Sensor Harness Connector
      G02450491Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check voltage between APP sensor terminal 2 and ground with CONSULT-II or tester.
      • Voltage: Approximately 5V 
      Fig 3: Checking Voltage Between APP Sensor Connector Terminal 2 And Ground
      G02450492Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    • OK : GO TO  4.
    • NG : GO TO 3.
  3. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors M58, F26
    • Harness for open or short between ECM and accelerator pedal position sensor
      • : Repair open circuit or short to ground or short to power in harness or connectors.
  4. CHECK APP SENSOR 2 POWER SUPPLY CIRCUIT-I 

    Check voltage between APP sensor terminal 1 and ground with CONSULT-II or tester.

    • Voltage: Approximately 5V 
    Fig 4: Checking Voltage Between APP Sensor Connector Terminal 1 & Ground
    G02450493Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    • OK : GO TO  10.
    • NG : GO TO 5.
  5. 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 1 and ECM terminal 91.

      Refer to WIRING DIAGRAM .

      • Continuity should exist. 

    OK or NG 

    • OK : GO TO  7.
    • NG : GO TO 6.
  6. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors M58, F26
    • Harness for open between ECM and accelerator pedal position sensor
      • : Repair or replace open circuit.
  7. CHECK APP SENSOR 2 POWER SUPPLY CIRCUIT-III 

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

    APP SENSOR 2 POWER SUPPLY CIRCUIT-III - ECM CONNECTOR TERMINAL REFERENCE

    ECM terminal Sensor terminal Reference Wiring Diagram
    91 APP sensor terminal 1 WIRING DIAGRAM 
    47 Electric throttle control actuator terminal 1 WIRING DIAGRAM 

    OK or NG 

    • OK : GO TO 8.
    • NG : Repair short to ground or short to power in harness or connectors.
  8. CHECK THROTTLE POSITION SENSOR 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    • OK : GO TO  16.
    • NG : GO TO 9.
  9. REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR 
    1. Replace the electric throttle control actuator.
    2. Perform "THROTTLE VALVE CLOSED POSITION LEARNING ".
    3. Perform "IDLE AIR VOLUME LEARNING ".
      • : INSPECTION END 
  10. 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 terminal 4 and ECM terminal 82, APP sensor terminal 5 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  12.
    • NG : GO TO 11.
  11. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors M58, F26
    • Harness for open or short between ECM and accelerator pedal position sensor
      • : Repair open circuit or short to ground or short to power in harness or connectors.
  12. CHECK APP SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Check harness continuity between ECM terminal 106 and APP sensor terminal 3, ECM terminal 98 and APP sensor terminal 6.

      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  14.
    • NG : GO TO 13.
  13. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors M58, F26
    • Harness for open or short between ECM and accelerator pedal position sensor
      • : Repair open circuit or short to ground or short to power in harness or connectors.
  14. CHECK APP SENSOR 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    • OK : GO TO  16.
    • NG : GO TO 15.
  15. 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 
  16. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    • : INSPECTION END 
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