Inspection Procedure 7: Shift Shock when Shifting from N to R and Long Delay




COMMENTS ON TROUBLE SYMPTOM




PROBABLE CAUSES



  • Malfunction of low-reverse solenoid valve
  • Malfunction of input shaft speed sensor
  • Malfunction of the inhibitor switch
  • Abnormal reverse clutch pressure
  • Abnormal low-reverse brake pressure
  • Malfunction of accelerator pedal position sensor
  • Malfunction of the reverse clutch
  • Malfunction of low-reverse brake
  • Malfunction of valve body
  • Malfunction of the engine-A/T-ECU

DIAGNOSIS PROCEDURE


STEP 1. M.U.T.-III actuator test


Item 1: 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 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 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) set?

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 4.

STEP 4. M.U.T.-III data list


Item 12: 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 2: Accelerator pedal position sensor (Refer to data list reference table ).

Q. Is the check result normal?

Go to Step 9.
Check the accelerator pedal position sensor system (Refer to GROUP 13A - Troubleshooting, Inspection Chart For Diagnosis Code ).

STEP 9. 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 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.