This lift truck will start and move in both forward and reverse. Once it gets going, it stops (PMT trip?) If I continue to puck on the joystick after a second or two. If it stops, I need to turn the key on and off before it will move.

If after starting, I return the joystick to center before it kicks off, I can repeat this start, coast, start, coast without triping the PMT.

Any ideas on what is most likely to.cause this?