NSM Satellite 200 - Carriage or CCU

I purchased a non-working 1982 NSM satellite 200 in excellent shape. Initially the carriage wouldn't move. I replaced a burnt-out relay on the CCU. Now the carriage will track to a 45, load it, needle arm will move into position, and then the 45 is rejected, and the carriage will track about 10 spaces right and stop. No error codes. The needle arm will also not change position to select A or B side of a 45. Also, when I use the test button on the CCU, the carriage will move and the counter will go up to 250, after which it restarts at 200. Does anyone have any advice on whether this is a carriage problem, or still a fault on the CCU? Any suggestions?