Inspection Procedure 3: Does not Move Forward


COMMENTS ON TROUBLE SYMPTOM



PROBABLE CAUSES



  • Malfunction of underdrive solenoid valve
  • Malfunction of inhibitor switch
  • Abnormal line pressure
  • Malfunction of the underdrive clutch
  • Malfunction of valve body
  • Malfunction of the oil pump
  • Malfunction of the A/T-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III actuator test
Item 02: 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 diagnosis code
Either of diagnosis codes P1770 (P0705) or P1771 (P0705) is set, inhibitor switch is defective.

Q. Are diagnosis codes P1770 (P0705) or P1771 (P0705) output?
YES <diagnosis code P1770 (P0705) is set> : Refer to diagnosis code P1770 (P0705): Inhibitor switch system .
YES <diagnosis code P1771 (P0705) is set> : Refer to diagnosis code P1771 (P0705): Inhibitor switch system .
Go to Step 3.

STEP 3. Underdrive solenoid valve check
(1)Turn the ignition switch to the ON position.
(2)Shift the selector lever from N to D range.
(3)Confirm the operating sound of the underdrive solenoid valve.
OK: Operating sound can be heard.

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

STEP 4. Hydraulic pressure test
Measure the hydraulic pressure of the underdrive clutch when the selector lever is at the L range.
OK: Refer to .

Q. Is the check result normal?
Go to Step 7.
Go to Step 5.

STEP 5. A/T-ECU replacement
(1)Replace the A/T-ECU.
(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 6.
The inspection is complete.

STEP 6. 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 7.
The inspection is complete.

STEP 7. Oil pump check
(1)If the damage is in the oil pump assembly, replace the oil pump assembly.
(2)Test drive the vehicle.
(3)Verify that the condition described by the customer exists.

Q. Is the check result normal?
Go to Step 8.
The inspection is complete.

STEP 8. Underdrive clutch check
(1)Check the facing for seizure and the piston seal ring for damage and interference with the retainer.
(2)Test drive the vehicle.
(3)Verify that the condition described by the customer exists.

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