Roland,

I wonder if a "test exchange" system could be implemented. When really
stumped, in a pinch, it would be nice to get a known working controller and/or
keypad, and cables, on a 7 day debug loan - a credit card buys it, if not
returned in time. That would allow eliminating the servos, and perhaps narrow
down the problem to one of the 3 other components - controller, keypad, or
cables. Such a plan would eliminate time and money lost in shipping the mount
back, which would also needlessly tie up your staff. The test package wouldn't
even have to be the very latest hardware version, so long as it is
known/tested to be in good working order, back at the factory.

Otherwise, one would have to try finding a nearby "good Samaritan", from
the AP group perhaps, who owns the same mount, to try a component swap test
with his controller/cables.

Joe