NO.12 TORQUE CONVERTER CLUTCH (TCC) NON-OPERATION [JA5A-EL]


12	Torque converter clutch (TCC) non-operation
DESCRIPTION	• TCC does not operate when vehicle reaches TCC operation range.
POSSIBLE CAUSE	• Basically, the TCC does not operate when fail-safe is operating. Verify the DTC first. If the TCC operates when driving at high speeds only, the malfunction (improper adjustment) is in the HOLD switch circuit or TR switch circuit. 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. TCC piston slippage, burnt - Line pressure low • Incorrect throttle position signal • Input/turbine speed sensor malfunction • TFT sensor malfunction • Sensor ground malfunction • VSS malfunction • Malfunction of output solenoid valve system (Sticking) • TCC solenoid valve malfunction • Malfunction of control valve body system (Poor operation, sticking) • TCC piston hydraulic pressure system malfunction 2. TP sensor malfunction (Not operating linearly) 3. Input/turbine speed sensor or VSS malfunction Note • Before following the troubleshooting steps, make sure that the Automatic Transaxle On-Board Diagnostic and Automatic Transaxle Basic Inspection are conducted.


STEP	INSPECTION		ACTION
1	With ignition switch at the ON position, does the HOLD indicator light indication correspond to the HOLD switch operation?	Yes	Go to the next step.
1		No	Go to No.26 "HOLD INDICATOR LIGHT DOES NOT ILLUMINATE WHEN HOLD SWITCH IS TURNED TO ON", or No.27 "HOLD INDICATOR LIGHT ILLUMINATE WHEN HOLD SWITCH IS NOT TURNED TO ON".
2	Disconnect the TCM connector. Is the resistance between the ground terminals 1C, 1Y at TCM connector and body ground less than 5.0 ohm?	Yes	Go to the next step.
2		No	Repair open ground circuit.
3	Remove the torque converter. Inspect the torque converter. (See ATX Workshop Manual.) Is the torque converter normal?	Yes	Overhaul the control valve body and repair or replace any malfunctioning parts. (See ATX Workshop Manual.) If any problem remains, replace or overhaul the transaxle and repair or replace any malfunctioning parts. (See ATX Workshop Manual.)
3		No	Replace the torque converter.
4	• Verify the test results. - If normal, return to the diagnostic index to service any additional symptoms. - If the malfunction remains, inspect the related Service Bulletins and/or On-line Repair Information and perform repair or diagnosis. • If the vehicle is repaired, troubleshooting is completed. • If the vehicle is not repaired or additional diagnostic information is not available, replace the TCM.