What was found
(CAN) IN TAXI, CREW EXPERIENCED SUDDEN LOSS OF STEERING CONTROL AIRCRAFT VEERED SHARPLY TO ONE SIDE. INVESTIGATION REVEALED THAT SPRING PIN SECURING CCX-A1-10 COUPLING TO STEERING TILLER HAD FALLEN OUT OF POSITION. THE COUPLING IN TURN FELL FROM INSTALLED POSITION AND LANDED ON FLOOR. LOSS OF UNIVERSAL COUPLING WHICH DISCONNECTED THE STEERING TILLER HANDLE FROM THE POTENTIOMETER WAS CAUSE OF STEERING LOSS.