NO.12 TORQUE CONVERTER CLUTCH (TCC) NON-OPERATION [GF4AX-EL]


12	Torque converter clutch (TCC) non-operation
DESCRIPTION	• TCC does not operate when vehicle reaches TCC operation range.
POSSIBLE CAUSE	• TCC does not operate when the 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 O/D OFF 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 • TP sensor malfunction • Input/turbine speed sensor malfunction • TFT sensor malfunction • Sensor GND malfunction • VSS malfunction • Output solenoid valve system malfunction (Stuck) • TCC solenoid valve malfunction • Control valve body system malfunction (Poor operation, stuck) • TCC hydraulic pressure system malfunction 2. TP sensor (Not operating linearly) malfunction 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	Turn the ignition switch to the ON position. Does the O/D OFF indicator light indication correspond to the O/D OFF switch operation?	Yes	Go to the next step.
1		No	Go to No.26 "O/D OFF INDICATOR LIGHT DOES NOT ILLUMINATE WHEN O/D OFF SWITCH IS TURNED ON", or No.27 "O/D OFF INDICATOR LIGHT ILLUMINATES WHEN O/D OFF SWITCH IS NOT TURNED ON".
2	Inspect the value at the following PCM PIDs using the WDS or equivalent. (See PCM INSPECTION [L3 R.H.D.].) • TP • TSS • VSS Are the PID values normal?	Yes	Go to the next step.
2		No	Repair or replace any malfunctioning parts according to the inspection results.
3	Disconnect the PCM connector. Is the resistance between the GND terminals 4, 5, 14, 54 or 80 at the PCM connector and body GND less than 5.0 ohms?	Yes	Go to the next step.
3		No	Repair open GND circuit.
4	Turn the ignition switch to the ON position. Connect the WDS or equivalent to DLC-2. Simulate TCC PID for ON. Is operating sound of the TCC control solenoid heard?	Yes	Replace the control valve body and repair or replace any malfunctioning parts. (See ATX Workshop Manual (GF4AX-EL)) If any problem remains, replace the transaxle and repair or replace any malfunctioning parts. (See ATX Workshop Manual (GF4AX-EL))
4		No	Inspect connection of the TCC control solenoid terminal on the ATX for bent terminals, damage, corrosion or looseness. Inspect for stuck TCC control solenoid? (See Operating Inspection (On-vehicle Inspection).) If the shift solenoids normal, inspect for open or short circuit between the PCM terminal 65 and the TCC control solenoid terminal D.
5	• Verify the test results. - If normal, return to the diagnostic index to service any additional symptoms. - If the malfunction remains, inspect the related Service 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 PCM.