I have a IRB2400/16 with S4C+ bay that has been working flawlessly for couple of years, gone into storage for a year (clean, dry) and now when turning back on gives an error 38653, Drive unit curr controller saturated" on joint 4 as soon as we try to jog it. All other joints move fine.
I have checked cabling, measured 6.5R between UVW phases of the joint 4 up until the connector going into the Drive Unit 1, DSQC 346E. As motor 4 and 6 are same model I even swapped the UVW plugs between to see if the joint 6 would fail instead but it's still joint 4 failing which seems to indicate the issue would be more on the Drive Unit side.
The robot config was working fine before so I have big doubts the motor config is an issue. The Controller was fully disconnected while in storage so I am quite flabbergasted that the Drive Unit would die out of the blue without any fault or crash? Anybody hit the same problem, any advice?