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Home >> Nissan-Datsun >> 2002 >> Sentra SE-R, Automatic >> Repair and Diagnosis >> Transmission >> Automatic Trans >> Automatic Transaxle Re4F04B >> DTC P0731 A/T 1ST Gear Function >> Diagnostic Procedure
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Diagnostic Procedure

  1. CHECK VALVE RESISTANCE
    1. Remove control valve assembly. Refer to REMOVAL .
      • Shift solenoid valve A
      • Shift solenoid valve B
    2. Check resistance between terminal cord assembly F30 terminals 1 and 2, and ground.
      Fig 1: Checking Resistance Between Terminal Cord Assembly F30 Terminals 1 And 2, And Ground
      G02016690Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO 2.
    2. NG: Repair or replace damaged parts.
  2. CHECK VALVE OPERATION
    1. Remove control valve assembly. Refer to REMOVAL .
      • Shift solenoid valve A
      • Shift solenoid valve B
    2. Check solenoid valve by listening for its operating sound while applying battery voltage and ground to the solenoid.
      Fig 2: Checking Shift Valve Operation
      G02016691Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO 3.
    2. NG: Repair or replace shift solenoid valve assembly.
  3. CHECK CONTROL VALVE
    1. Disassemble control valve assembly. Refer to DISASSEMBLY .
    2. Check to ensure that:
      • Valve, sleeve and plug slide along valve bore under their own weight.
      • Valve, sleeve and plug are free from burrs, dents and scratches.
      • Control valve springs are free from damage, deformation and fatigue.
      • Hydraulic line is free from obstacles.
      Fig 3: Checking Control Valve
      G02016692Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO 4.
    2. NG: Repair control valve assembly.
  4. CHECK DTC

    Perform DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION PROCEDURE .

    OK or NG 

    1. OK: INSPECTION END 
    2. NG: Check control valve again. Repair or replace control valve assembly.