Inspection Procedure 9: Shift Shock and Slipping


COMMENTS ON TROUBLE SYMPTOM



PROBABLE CAUSES



  • Malfunction of each solenoid valve
  • Abnormal line pressure
  • Malfunction of valve body
  • Malfunction of oil pump
  • Malfunction of each brake or each clutch
  • Malfunction of the engine-A/T-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III actuator test

  • Item 1: Low-reverse solenoid valve
  • Item 2: Underdrive solenoid valve
  • Item 3: Second solenoid valve
  • Item 4: Overdrive solenoid valve
  • Item 5: Reduction solenoid valve
OK: Operating sound can be heard.

Q. Is the check result normal?
Go to Step 2.
Replace the defective solenoid valve.

STEP 2. M.U.T.-III data list

  • Item 11: Shift position (Refer to data list reference table ).
  • Item 12, 13, 14, 15, 16: Each solenoid valve duty ratio (Refer to data list reference table ).

Q. Is the check result normal?
Go to Step 3.
Replace the engine-A/T-ECU.

STEP 3. Hydraulic pressure test
Check all hydraulic pressures within the standard value.
OK: Refer to .

Q. Is the check result normal?
Go to Step 6.
Go to Step 4.

STEP 4. Line pressure adjustment
(1)Adjust the line pressure (Refer to ).
(2)Test drive the vehicle.
(3)Verify that the condition described by the customer exists.

Q. Does a malfunction take place again?
Go to Step 5.
The inspection is complete.

STEP 5. Valve body disassembly clean and assembly
(1)Check the bolts for looseness and the O-ring, solenoid valve and valve body for damage.
Replace the valve body assembly if the damages are thought to be irreparable.
(2)Test drive the vehicle.
(3)Verify that the condition described by the customer exists.

Q. Does a malfunction take place again?
Check the oil pump for incorrect installation, damage and etc., and replace the oil pump assembly if necessary (The oil pump cannot be disassembled).
The inspection is complete.

STEP 6. Each clutch and brake check
Check the facing for seizure and the piston seal ring for damage and interference with the retainer.

Q. Is the check result normal?
The inspection is complete.
Repair or replace each clutch and brake.