Inspection Procedure 13: Gear shift does not occur with 3rd <=> 4th


COMMENTS ON TROUBLE SYMPTOM


When the gear does not shift from 3rd to 4th and from 4th to 3rd, the cause is probably a malfunction of inhibitor switch system, shift solenoid No.2 system, clutch control solenoid No.2 system, or valve body.

PROBABLE CAUSES



DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III data list

  • Refer to Data List Reference Table .

    1. Item 23: Inhibitor switch P
    2. Item 24: Inhibitor switch R
    3. Item 25: Inhibitor switch N
    4. Item 26: Inhibitor switch D

Q. Is the check result normal?
Go to Step 3.
Go to Step 2.

STEP 2. Inhibitor switch continuity check
Refer to .

Q. Is the check result normal?
Go to Step 3.
Replace the inhibitor switch.

STEP 3. M.U.T.-III actuator test
Item 2: Shift solenoid No.2
OK: Operating sound can be heard.

Q. Is the check result normal?
Go to Step 4.
Repair the shift solenoid No.2 system.

STEP 4. Retest the system
If the trouble symptom is not solved, replace the valve body. Then, check the trouble symptom again.

Q. Is the trouble symptom reproduced?
Go to Step 5.
This diagnosis is complete.

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. Is the trouble symptom reproduced?
Check the clutches and brakes for damage, and replace if necessary. (It is highly possible that the clutch C2 and one-way clutch F1 that operate at shift change between 3rd and 4th are damaged.)
This diagnosis is complete.