[23A] AUTOMATIC TRANSMISSION (FF) - - TROUBLESHOOTING <A/T> - SYMPTOM PROCEDURES - Inspection Procedure 3: Does not Move Forward | PRINT PAGE / INDEX / PRIOR / NEXT

Inspection Procedure 3: Does not Move Forward
COMMENTS ON TROUBLE SYMPTOM If the vehicle does not move forward when the selector lever is shifted to D, sport mode L, or 2 range while the engine is idling, the cause is probably abnormal line pressure or a malfunction of the underdrive clutch or valve body.
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 engine-A/T-ECU
DIAGNOSIS PROCEDURE
STEP 1. MUT-II/III actuator test Item 02: Underdrive solenoid valve OK: Operating sound can be heard. Q: Is the check result normal? YES: Go to Step 2. NO: Replace the underdrive solenoid valve.
STEP 2. MUT-II/III data list Item 61: Inhibitor switch (Refer to data list reference table .) Q: Is the check result normal? YES: Go to Step 3. NO: Refer to inspection procedure 16: Inhibitor switch system <4G63, 4G64>, <4G69>.
STEP 3. Underdrive solenoid valve check Turn the ignition switch to the ON position. Shift the selector lever from N to D range. Confirm the operating sound of the underdrive solenoid valve. OK: Operating sound can be heard. Q: Is the check result normal? YES: Go to Step 4. NO: Replace the engine-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 (Refer to ). OK: Refer to . Q: Is the check result normal? YES: Go to Step 7. NO: Go to Step 5.
STEP 5. Engine-A/T-ECU replacement Replace the engine-A/T-ECU. Test drive the vehicle. Verify that the condition described by the customer exists. Q: Does a malfunction take place again? YES: Go to Step 6. NO: The inspection is complete.
STEP 6. Valve body disassembly clean and assembly 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. Test drive the vehicle. Verify that the condition described by the customer exists. Q: Does a malfunction take place again? YES: Go to Step 7. NO: The inspection is complete.
STEP 7. Oil pump check If the damage is in the oil pump assembly, replace the oil pump assembly. Test drive the vehicle. Verify that the condition described by the customer exists. Q: Is the check result normal? YES: Go to Step 8. NO: The inspection is complete.
STEP 8. Underdrive clutch check Check the facing for seizure and the piston seal ring for damage and interference with the retainer. Test drive the vehicle. Verify that the condition described by the customer exists. Q: Is the check result normal? YES: The inspection is complete. NO: Repair or replace the underdrive clutch.

[23A] AUTOMATIC TRANSMISSION (FF) - - TROUBLESHOOTING <A/T> - SYMPTOM PROCEDURES - Inspection Procedure 3: Does not Move Forward | PRINT PAGE / INDEX / PRIOR / NEXT

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