Mike,?
Super! Congrats and good job. Although in general the components absolutely should not be corroding there are differing environments that do indeed have much higher prolonged humidity. The cables and their contacts all use gold plated components. Also - do you have it with the cover in place? If not I'd suggest that had a compounding effect. Where is it stored generally??
As for testing for the problem. First the fact that the motor runs away when you remove the cable says nothing about anything! This is normal and expected. The cable, which carries the motor encoder signal is absolutely required - remove it and the motor by necessity will run away! This alone doesn't suggest anything. But - if the run away happens when the cable is plugged in it is, as noted previously, one of those 3 causes and the cable is the most likely. That stated it is still very rare to have any cable fail. But it happens. Based on your description of mold I'd say it has a higher likelihood - although the jack itself would then fall in to that suspect category as well.
Back to testing: the test I described is the best way to determine where the cause is. If by swapping cables the problem moves to the other motor then it is the ServoCAT - the original axis system internally. If it does not move then it is the original fault axis cable or board/encoder. You can further pin it down IF the cables are removable (or like in your case you can make another one up) and you can then try a different cable on that axis to determine, (assuming that the new cable itself is good) either the motor itself is bad or the original cable is bad. If the former the motor assembly would need to be removed and sent in for Bill to replace the motor encoder module. These are very reliable but do occasionally fail.?
Have a good weekend! Enjoy.
Gary Myers?
