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HOMESERVICE MANUALSNISSAN-DATSUN2004ALTIMA S, AUTOMATICREPAIR AND DIAGNOSIS (SINGLE PAGE)ENGINE PERFORMANCEENGINE CONTROL SYSTEM - 2.5LDTC P2138: APP SENSORDIAGNOSTIC PROCEDURE
2004 Nissan-Datsun Altima S, Automatic

Diagnostic Procedure

2004 Nissan-Datsun Altima S, AutomaticSECTION Diagnostic Procedure
  1. CHECK GROUND CONNECTIONSĀ 
    1. Turn ignition switch OFF.
    2. Loosen and retighten three ground screws on the body. Refer to "GROUND INSPECTIONĀ ".
      Fig 1: Checking Ground Connections
      G02884924Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG

    1. OK : GO TO 2.
    2. NG : Repair or replace ground connections.
  2. CHECK APP SENSOR 1 POWER SUPPLY CIRCUITĀ 
    1. Disconnect accelerator pedal position (APP) sensor harness connector.
    2. Turn ignition switch ON.
      Fig 2: Disconnecting Accelerator Pedal Position (APP) Sensor Harness Connector
      G02884925Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check voltage between APP sensor terminal 2 and ground with CONSULT-II or tester.

      Voltage: Approximately 5VĀ 

      Fig 3: Checking Voltage Between APP Sensor Terminal 2 & Ground
      G02884926Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG

    1. OK : GO TO Ā 4.
    2. NG : GO TO 3.
  3. DETECT MALFUNCTIONING PARTĀ 

    Check the following.

    • Harness connectors E21, F34
    • Harness for open or short between ECM and accelerator pedal position sensor
    1. : Repair open circuit or short to ground or short to power in harness or connectors.
  4. CHECK APP SENSOR 2 POWER SUPPLY CIRCUIT-IĀ 

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

    Voltage: Approximately 5VĀ 

    Fig 4: Checking Voltage Between APP Sensor Terminal 1 & Ground
    G02884927Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG

    1. OK : GO TO Ā 10.
    2. NG : GO TO 5.
  5. CHECK APP SENSOR 2 POWER SUPPLY CIRCUIT-IIĀ 
    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 DiagramĀ .

      Continuity should exist.Ā 

    OK or NG

    1. OK : GO TO Ā 7.
    2. NG : GO TO 6.
  6. DETECT MALFUNCTIONING PARTĀ 

    Check the following.

    • Harness connectors E21, F34
    • Harness for open between ECM and accelerator pedal position sensor
    1. : Repair or replace open circuit.
  7. CHECK APP SENSOR 2 POWER SUPPLY CIRCUIT-IIIĀ 

    Check the following.

    • Harness for short to power and short to ground, between the following terminals.
    ECM TERMINALS REFERENCE

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

    OK or NG

    1. OK : GO TO 8.
    2. NG : Repair short to ground or short to power in harness or connectors.
  8. CHECK THROTTLE POSITION SENSORĀ 

    Refer to "COMPONENT INSPECTIONĀ ".

    OK or NG

    1. OK : GO TO Ā 16.
    2. NG : GO TO 9.
  9. REPLACE ELECTRIC THROTTLE CONTROL ACTUATORĀ 
    1. Replace the electric throttle control actuator.
    2. Perform "THROTTLE VALVE CLOSED POSITION LEARNINGĀ ".
    3. Perform "IDLE AIR VOLUME LEARNINGĀ ".
    1. >> INSPECTION ENDĀ 
  10. CHECK APP SENSOR GROUND CIRCUIT FOR OPEN AND SHORTĀ 
    1. Turn ignition switch OFF.
    2. Check harness continuity between APP sensor terminal 4, 5 and ground. Refer to Wiring DiagramĀ .

      Continuity should exist.Ā 

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

    OK or NG

    1. OK : GO TO Ā 12.
    2. NG : GO TO 11.
  11. DETECT MALFUNCTIONING PARTĀ 

    Check the following.

    • Harness connectors E21, F34
    • Harness for open or short between ECM and accelerator pedal position sensor
    • Harness for open or short between TCM and accelerator pedal position sensor
    1. : 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 SHORTĀ 
    1. Disconnect ECM harness connector.
    2. Check harness continuity between ECM terminal 106 and APP sensor terminal 3, ECM terminal 98 and APP sensor terminal 6. Refer to Wiring DiagramĀ .

      Continuity should exist.Ā 

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

    OK or NG

    1. OK : GO TO Ā 14.
    2. NG : GO TO 13.
  13. DETECT MALFUNCTIONING PARTĀ 

    Check the following.

    • Harness connectors E21, F34
    • Harness for open or short between ECM and accelerator pedal position sensor
    1. : Repair open circuit or short to ground or short to power in harness or connectors.
  14. CHECK APP SENSORĀ 

    Refer to "COMPONENT INSPECTIONĀ ".

    OK or NG

    1. OK : GO TO Ā 16.
    2. NG : GO TO 15.
  15. REPLACE ACCELERATOR PEDAL ASSEMBLYĀ 
    1. Replace accelerator pedal assembly.
    2. Perform "ACCELERATOR PEDAL RELEASED POSITION LEARNINGĀ ".
    3. Perform "THROTTLE VALVE CLOSED POSITION LEARNINGĀ ".
    4. Perform "IDLE AIR VOLUME LEARNINGĀ ".
    1. >> INSPECTION ENDĀ 
  16. CHECK INTERMITTENT INCIDENTĀ 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTĀ ".

    1. >> INSPECTION ENDĀ 
RENDER: 1.0x

NO RELATED

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