Torque Converter Does Not Lock Up

1. Faulty or misadjusted throttle sensor.
2. Faulty revolution sensor.
3. Faulty speed sensor.
4. Faulty or misadjusted inhibitor switch.
5. Faulty fluid temperature sensor.
6. Incorrect line pressure.
7. Faulty lock-up solenoid.
8. Faulty control valve assembly.
9. Faulty torque converter.