Inspection Procedure 6: Shift Shock when Shifting from N to D and Long Delay


COMMENTS ON TROUBLE SYMPTOM



PROBABLE CAUSES



  • Malfunction of underdrive solenoid valve
  • Malfunction of input shaft speed sensor
  • Abnormal underdrive clutch pressure
  • Malfunction of accelerator pedal position sensor
  • Malfunction of the underdrive clutch
  • Malfunction of valve body
  • Malfunction of the engine-A/T-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III actuator test
Item 2: Underdrive solenoid valve
OK: Operating sound can be heard.

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

STEP 2. M.U.T.-III data list
Item 5: Input shaft speed sensor (Refer to data list reference table ).

Q. Is the check result normal?
Go to Step 3.
Refer to diagnosis code P1766: Input shaft speed sensor system .

STEP 3. M.U.T.-III data list
Item 13: Underdrive solenoid valve duty ratio (Refer to data list reference table ).

Q. Is the check result normal?
Go to Step 4.
Replace the engine-A/T-ECU.

STEP 4. Check when shift shock occurs.

Q. Does the shift shock occur when the vehicle starts moving?
Go to Step 6.
Go to Step 5.

STEP 5. Hydraulic pressure test
Measure the hydraulic pressure for underdrive clutch when the selector lever is shifted from N to D range.
OK: Refer to .

Q. Is the check result normal?
Go to Step 9.
Go to Step 8.

STEP 6. Check when shift shock occurs.

Q. Does the shift shock always occur?
Go to Step 8.
Go to Step 7.

STEP 7. M.U.T.-III data list
Item 2: Accelerator pedal position sensor (Refer to data list reference table ).

Q. Is the check result normal?
Go to Step 8.
Check the accelerator pedal position sensor system (Refer to GROUP 13A - Troubleshooting, Inspection Chart For Diagnosis Code ).

STEP 8. 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?
Go to Step 9.
The inspection is complete.

STEP 9. Underdrive clutch 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 the underdrive clutch.