Hi,
We have an 884 that came with this year's kit that only works in reverse. When we send it a nice 254, the Victor LED does turn green but the voltage is 0 V.
We discovered this problem on the ship day (sure, when else?), when our arm was only going down. We then noticed the fan had stopped and proceeded to replace the Victor.
Today I tested it again, hoping that the long months of dust gathering would have done it some good. Sure didn't.
So we pried it open and there was nothing wrong, apparently. No smell, no burn marks, nothing. We heated the MOSFETs a bit to see if it might have been a problem of cold solder joint, but it didn't help.
Any ideas?