Fashionable torque converters use electro hydraulic Regulate for your lock-up clutch. The hydraulic circuit which locks/unlocks the torque converter clutch is managed using hydraulic valves. The valves are actuated directly or indirectly by solenoids. Visual Inspection:  Start with a basic visual inspection. Look for any signs of leaks or problems https://torque-converter-clutch37025.blogsvila.com/34125247/the-ultimate-guide-to-torque-converter-clutch