A solenoid is really a linear electrical actuator. When is being energised (supplied with electric powered Electricity) it pushes or pulls a rod that is connected to the hydraulic valve. You will find different types of solenoid used for torque converter clutch Manage, but the basic principle of working is https://torque-converter-clutch95812.blogdanica.com/33935586/torque-converter-clutch-for-dummies