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NO.12 TORQUE CONVERTER CLUTCH (TCC) NON-OPERATION [FN4A-EL]

id0503a1801700

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 the fail-safe is operating. Verify the DTC first. 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 burned (1) Input sensor system malfunction • Transaxle fluid temperature sensor • Vehicle speed sensor • Input/turbine speed sensor • Sensor GND (2) Output solenoid valve system malfunction (Sticking) • Shift solenoid E malfunction • Shift solenoid A malfunction (3) Control valve body malfunction system (Poor operation, stuck) • TCC hydraulic pressure system 2. TP sensor malfunction (Not operating linear) 3. Input/turbine speed sensor or vehicle speed sensor malfunction 4. Brake switch malfunction (Always ON) 5. ECT sensor 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 | • With ignition switch at ON, does HOLD indicator light indication correspond to HOLD switch operation? | Yes | Go to next step.
No | Go to No.26 "HOLD INDICATOR LIGHT DOES NOT ILLUMINATE WHEN HOLD SWITCH IS TURNED ON", No.27 "HOLD INDICATOR LIGHT ILLUMINATES WHEN HOLD SWITCH IS NOT TURNED ON."
2 | • Check the value at the following PIDs using the WDS or equivalent. (See PCM INSPECTION [WITHOUT WU-TWC].) (See PCM INSPECTION [WITH WU-TWC].) - TP - VSS - TSS • Are PID values normal? | Yes | Go to next step.
No | Repair or replace any defective parts.
3 | • 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.
4 | • Check resistance between shift solenoid A and E control circuit at PCM connector and control valve body connector. • Check resistance between shift solenoid A and E circuit at PCM connector and control valve body connector. • Are the resistances less than 5.0 ohms? | Yes | Go to next step.
No | Repair shift solenoid A or E control. Reconnect PCM.
5 | • Inspect shift solenoid A and E. (See SOLENOID VALVE INSPECTION [FN4A-EL].) • Are the shift solenoids operating properly? | Yes | Replace PCM.
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].)
6 | • Verify test results. - If normal, return to diagnostic index to service any additional symptoms. - If malfunction remains, inspect related Service Information and perform repair or diagnosis. • If vehicle repaired, troubleshooting completed. • If vehicle not repaired or additional diagnostic information not available, replace PCM.