I'm using THC Module with Mach3. Inputs are correct. Turning on test mode on THC module generates THC Up, THC Down, THC On signals and torch is moving op and down however. Turning on Down or Up singal is moving torch only a 2-3mm and then it stop no mater if input is stil on or off. Only turning oposite signal and moving torch oposite way will reset it. For example im turning on THC Up signal, torch will move Up a little bit and then stop i can turn on/off THC Up singal but nothing will happen only turning on Down signal will cause to move torch down and then i can move torch Up again.

What is causing the problem and how to fix it?

Load the plasma screen set, and there are two variables, of how much the Z axis should move up or down and with what speed.