A/T Does Not Hold Lock-up Condition

WARNING: This page is about a different car, the 2005 Nissan Quest. However, it is still accessible from the selected car via links, so may be relevant.

SYMPTOM:

A/T does not hold lock-up condition for more than 30 seconds.

CHECK SELF-DIAGNOSTIC RESULTS
Does self-diagnosis show damage to engine speed signal circuit after cruise test?

Fig 1: Checking Engine Speed Signal Circuit
Courtesy of NISSAN MOTOR CO., U.S.A.

Yes or No
- Yes: Check engine speed signal circuit. Refer to "DTC P0725 ENGINE SPEED SIGNAL ".
- No: GO TO 2.
CHECK A/T FLUID CONDITION
1. Remove oil pan.
2. Check A/T fluid condition.
  
  Fig 2: Checking A/T Fluid Condition
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG
- OK: GO TO 4.
- NG: GO TO 3.
DETECT MALFUNCTIONING ITEM
1. Remove control valve assembly. Refer to "CONTROL VALVE ASSEMBLY AND ACCUMULATORS ".
2. Check the following items:
  - Torque converter clutch control valve
  - Pilot valve
  - Pilot filter
3. Disassemble A/T.
4. Check torque converter and oil pump assembly.
OK or NG
- OK: GO TO 5.
- NG: Repair or replace damaged parts.
DETECT MALFUNCTIONING ITEM
1. Remove control valve assembly. Refer to "CONTROL VALVE ASSEMBLY AND ACCUMULATORS ".
2. Check the following items:
  - Torque converter clutch control valve
  - Pilot valve
  - Pilot filter
OK or NG
- OK: GO TO 5.
- NG: Repair or replace damaged parts.
CHECK SYMPTOM
Check again.

OK or NG
- OK: INSPECTION END
- NG: GO TO 6.
CHECK TCM INSPECTION
1. Perform TCM input/output signal inspection. Refer to "TCM TERMINALS AND REFERENCE VALUE ".
2. If NG, recheck TCM pin terminals for damage or loose connection with harness connector.
OK or NG
- OK: INSPECTION END
- NG: Repair or replace damaged parts.