(From the Service Manual)
4,013.43 (0x240D) PC_DEV_FAULT_ GEAR_GRIND: During power-on initialization, the engine is unable to disengage the process motor. Prior to declaring this fault, the engine has attempted to move the process motor through enough revolutions to disengage the head tilt mechanism, but the motor stalled. The X axis was then displaced to the right 0.15 inches and the disengage was repeated, but the motor stalled again. This fault is then declared. The head is unable to move on its tilt axis, perhaps because it is colliding with something (head restraint pin, cap, poorly installed ink loader, screwdriver.)
-Bill