Inspection Procedure 8: Shift shock when shifting from N to R and long delay


COMMENTS ON TROUBLE SYMPTOM


If abnormal shock or delay of two seconds or more occurs when the selector lever is shifted from N to R range while the engine is idling, the cause is probably abnormal pressure in reverse clutch and low-reverse clutch or a malfunction of the reverse clutch, low-reverse brake, valve body or throttle position sensor.

PROBABLE CAUSES



DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III actuator test
Item 01: Low-reverse solenoid valve
OK: Operating sound can be heard.

Q. Is the check result normal?
Go to Step 2.
Replace the low-reverse solenoid valve.

STEP 2. M.U.T.-III data list
Item 0001: Input shaft speed sensor (Refer to data list reference table ).

Q. Is the check result normal?
Go to Step 3.
Refer to diagnosis code 22: Input shaft speed sensor system .

STEP 3. M.U.T.-III data list
Item 61: Inhibitor switch (Refer to data list reference table ).

Q. Is the check result normal?
Go to Step 4.
Refer to Inspection procedure 16: Inhibitor switch system .

STEP 4. M.U.T.-III data list
Item 31: Low-reverse solenoid valve duty ratio (Refer to data list reference table ).

Q. Is the check result normal?
Go to Step 5.
Replace the engine-A/T-ECU.

STEP 5. Check when shift shock occurs.

Q. Does the shift shock occur when the vehicle starts moving?
Go to Step 7.
Go to Step 6.

STEP 6. Hydraulic pressure test
Measure the hydraulic pressure for reverse clutch and low-reverse clutch when the selector lever is shifted from N to R range.
OK: Refer to .

Q. Is the check result normal?
Go to Step 10.
Go to Step 9.

STEP 7. Check when shift shock occurs.

Q. Does the shift shock always occur?
Go to Step 9.
Go to Step 8.

STEP 8. M.U.T.-III data list
Item 11: Throttle position sensor (Refer to data list reference table ).

Q. Is the check result normal?
Go to Step 9.
Check the throttle position sensor system (Refer to GROUP 13A, Troubleshooting <Except for Hong Kong and Singapore> or Refer to GROUP 13B, Troubleshooting <Vehicles for Hong Kong and Singapore>).

STEP 9. Valve body disassembly clean and assembly
(1)Check the bolts for looseness and the O-ring, solenoid valve, springs 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 10.
The inspection is complete.

STEP 10. Reverse clutch and low-reverse 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 the reverse clutch and low-reverse brake.