NO.16 JUDDER UPON TORQUE CONVERTER CLUTCH (TCC) OPERATION (EXCEPT FOR GENERAL (L.H.D.) SPECS. SPORT AT) [FN4A-EL]


id0503a18021a6

16

Judder upon torque converter clutch (TCC) operation

DESCRIPTION

• Vehicle jolts when TCC is engaged.

POSSIBLE CAUSE

• Poor TCC engagement due to either slippage because the TCC is stuck or the line pressure is low
Caution
• If the TCC is stuck, inspect it. In addition, inspect the oil cooler for foreign particles which may have mixed in with the ATF.
1. Torque converter clutch piston slipped, burned
• Line pressure high
• Shift solenoid A malfunction
• Control valve body malfunction
• Body GND malfunction
• Pressure control solenoid malfunction
2. Signal malfunction
• Vehicle speed sensor malfunction
• Sensor GND malfunction
• TFT sensor malfunction
• TP sensor malfunction or mis-adjustment
• Input/turbine speed sensor malfunction
3. Torque converter malfunction
Note
• Before following troubleshooting steps, make sure that Automatic Transaxle On-Board Diagnostic and Automatic Transaxle Basic Inspection are conducted.

Diagnostic procedure

STEP

INSPECTION

ACTION

1
Check the value at the following PIDs using the WDS or equivalent. (See PCM INSPECTION [LF, L3].)
• TSS
Are PID values okay?
Yes
Go to next step.
No
Repair or replace any defective parts.
2
Disconnect PCM. Is resistance between ground terminal at PCM connector and body ground less than 5.0 ohms?
Yes
Go to next step.
No
Repair open ground circuit.
3
Check resistance between shift solenoid A control circuit at PCM connector and control valve body connector. Check resistance between shift solenoid A circuit at PCM connector and control valve body connector. Are the resistance less than 5.0 ohms?
Yes
Go to next step.
No
Repair shift solenoid A circuit.
4
Inspect shift solenoid. (See SOLENOID VALVE INSPECTION [FN4A-EL].) Is the solenoid valve operating properly?
Yes
Go to next step.
No
Overhaul control valve body and repair or replace any defective parts. (See ATX workshop manual (FN4A-EL) [1623-10-98E].) If problem remains, overhaul transaxle and repair or replace any defective parts. (See ATX workshop manual (FN4A-EL) [1623-10-98E].)
5
Check LPS PID value.
Is LPS PID value okay?
Yes
Overhaul control valve body and repair or replace any defective parts. (See ATX workshop manual (FN4A-EL) [1623-10-98E].) If problem remains, overhaul transaxle and repair or replace any defective parts. (See ATX workshop manual (FN4A-EL) [1623-10-98E].)
No
Replace PCM.
6
• Verify test results.
- If okay, return to diagnostic index to service any additional symptoms.
- If malfunction remains, inspect related Service informations and perform repair or diagnosis.
- If vehicle not repaired, trouble shooting completed.
- If vehicle not repaired or additional diagnostic information not available, replace PCM.