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Home >> Nissan-Datsun >> 2002 >> Sentra SE-R, Automatic >> Repair and Diagnosis (Single Page) >> External Pages >> Different variant/trim >> Section 10 (Automatic Transaxle Re4F03B) >> Diagnostic Trouble Code Definitions >> DTC P0744: A/T TCC S/V Function (Lock-Up) >> Diagnostic Procedure
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Diagnostic Procedure

WARNING: This page is about a different variant/trim than selected.
  1. CHECK SHIFT UP (D3 TO D4) 

    During CRUISE TEST - PART 1 , does A/T shift from D3 to D4 at the specified speed?

    Fig 1: Checking Shift Up (D3 To D4)
    G02015780Courtesy of NISSAN MOTOR CO., U.S.A.

    Yes or No 

    1. Yes: GO TO  10.
    2. No: GO TO 2.

  2. CHECK LINE PRESSURE 

    Perform line pressure test.

    Refer to LINE PRESSURE TEST .

    Fig 2: Line Pressure Specifications
    G02015781Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO 3.
    2. NG: GO TO  6.

  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
      G02015782Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

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

  4. CHECK SHIFT UP (D3 TO D4) 

    Does A/T shift from D3 to D4 at the specified speed?

    Yes or No 

    1. Yes: GO TO 5.
    2. No: Check control valve again. Repair or replace control valve assembly.

  5. CHECK DTC 

    Perform DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION PROCEDURE .

    OK or NG 

    1. OK: INSPECTION END 
    2. NG: GO TO  10. Check lock-up condition.
  6. CHECK LINE PRESSURE SOLENOID VALVE 
    1. Remove control valve assembly.

      Refer to REMOVAL .

    2. Check line pressure solenoid valve operation.

      Refer to COMPONENT INSPECTION .

      Fig 4: Checking Line Pressure Solenoid Valve
      G02015783Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO 7.
    2. NG: Replace solenoid valve assembly.

  7. CHECK CONTROL VALVE 
    1. Disassemble control valve assembly.

      Refer to DISASSEMBLY .

    2. Check line pressure circuit valves for sticking.
      • Pressure regulator valve
      • Pilot valve
      • Pressure modifier valve
      Fig 5: Checking Control Valve
      G02015784Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO 8.
    2. NG: Repair control valve.
  8. CHECK SHIFT UP (D3 TO D4) 

    Does A/T shift from D3 to D4 at the specified speed?

    Yes or No 

    1. Yes: GO TO 9.
    2. No: Check control valve again. Repair or replace control valve assembly.

  9. CHECK DTC 

    Perform DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION PROCEDURE .

    OK or NG 

    1. OK: INSPECTION END 
    2. NG: GO TO 10. Check for proper lock-up.

  10. CHECK LOCK-UP CONDITION 

    CRUISE TEST - PART 1 , does A/T perform lock-up at the specified speed?

    Fig 6: Checking Lock-Up Condition
    G02015785Courtesy of NISSAN MOTOR CO., U.S.A.

    Yes or No 

    1. Yes: CRUISE TEST - PART 1  again and return to the start point of this test group.
    2. No: GO TO 11.

  11. CHECK TORQUE CONVERTER CLUTCH SOLENOID VALVE 
    1. Remove control valve assembly.

      Refer to REMOVAL .

    2. Check torque converter clutch solenoid valve operation. Refer to TORQUE CONVERTER CLUTCH SOLENOID VALVE .
      Fig 7: Checking Torque Converter Clutch Solenoid Valve Operation
      G02015786Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO 12.
    2. NG: Replace solenoid valve assembly.

  12. CHECK CONTROL VALVE 
    1. Disassemble control valve assembly.

      Refer to DISASSEMBLY .

      Fig 8: Checking Control Valve
      G02015787Courtesy of NISSAN MOTOR CO., U.S.A.
    2. Check control valves for sticking.
      • Torque converter clutch control valve
      • Torque converter clutch relief valve

    OK or NG 

    1. OK: GO TO 13.
    2. NG: Repair control valve.

  13. CHECK LOCK-UP CONDITION 

    Does A/T perform lock-up at the specified speed?

    Yes or No 

    1. Yes: GO TO 14.
    2. No: Check control valve again. Repair or replace control valve assembly.

  14. CHECK DTC 

    Perform DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION PROCEDURE .

    OK or NG 

    1. OK: INSPECTION END 
    2. NG: Perform CRUISE TEST - PART 1  again and return to the start point of this test group.