Inspection Procedure 15: Gear shift does not occur with 5th <=> 6th

COMMENTS ON TROUBLE SYMPTOM

When the gear does not shift from 5th to 6th and from 6th to 5th, the cause is probably a malfunction of inhibitor switch system, C1 pressure control solenoid (SL1) system, C4 pressure control solenoid (SL4) system, or valve body.

PROBABLE CAUSES

Malfunction of inhibitor switch system
Malfunction of transmission control cable
Malfunction of C1 pressure control solenoid (SL1) system
Malfunction of C4 pressure control solenoid (SL4) system
Malfunction of valve body (SL1, SL4)
Malfunction of the A/T-ECU
A/T internal error (clutch C1, clutch C4, etc.)

DIAGNOSIS PROCEDURE

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

Refer to Data List Reference Table .

Item 24: Inhibitor switch P
Item 25: Inhibitor switch R
Item 26: Inhibitor switch N
Item 27: 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 5: Linear solenoid 1

Item 8: Linear solenoid 4

OK: Operating sound can be heard.

Q. Is the check result normal?

	Go to Step 4.

	Repair the C1 pressure control solenoid (SL1) system or C4 pressure control solenoid (SL4) system.

STEP 4. Check of inhibitor switch and transmission control cable

Check the installation status of inhibitor switch and transmission control cable.

Q. Is the check result normal?

	Go to Step 5.

	Adjust the inhibitor switch and the transmission control cable. (Refer to .)

STEP 5. 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 6.

	This diagnosis is complete.

STEP 6. 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 C1 and clutch C4 that operate at shift change between 5th and 6th are damaged.)

	This diagnosis is complete.