Multi-Point locking mechanisms used on sliding patio doors have been manufactured by Truth, Marvin, Fuhr, Hoppe or a half dozen others.  When the door is fully closed, the thumb turn latches at two, three or more points into keepers or around strikes in the jamb. Fifty percent of the time, maintenance issues with these high-security style locks can be contributed to the keepers, which may just be out of adjustment or alignment. With these designs, the thumb turn cannot move the latches until the door is completely closed and a “plunger”, protruding from the jam, presses