These are bad motor codes.
0016 Hardware tach error, any motor
0023 Crash stop encountered, any motor
0061 Crash stop 2 encountered, any motor
0068 Mechanism stalled, any motor
026a Z moved during target code execution.
026b Quick target search failed
Where did you get them from? Is LMU maintenance enabled? If so, what do the error logs show? You could also run the various tests that checkout the Z (test 550), theta (test 560) and the other motors to see if any fail.
By the way, are you sure it only happens servicing the CAP doors? You would think the problem would occur doing normal work.
When you open the door to check inside do you get a clue to which crashstop is encountered (the theta rotation assembly at one end, or the turntable up at the roof or on the floor, or the turntable at the end of travel etc)?. If not you can slowly turn them all to see if any are lumpy. Also check all the belts.
I hope its not the theta motor. It's a swine to get out.