Mazak M+ drive not powering up?

Hello,

A few weeks ago the "Y" axis drive did not fire up on our 1998 HTC400 horizontal machining center with M+ control. The Y axis supports the spindle.
The Y drive is in the middle of the drive section, the one on the left and the one on the right of it fire up. It finally fired up but next time we shut it down it would not fire up, no red lights, no power output.
We traded drives, it ran for a day or so and same thing but it fired up again the next day after several tries.
The machine ran fine for a couple of weeks, we just did not turn it off, worked fine, went in Saturday and it was off.
The only error messages is "missing amp" and a few other in the same area, the Y brake running off the drive has 24v running to it, not really sure what else could cause the problem.
The machine does not run much, things get a bit 'sticky" from sitting too much, we try and fire it up every week and run it for a few hours, the dead drive happens when you try and start the machine, Saturday morning was the first time it quit while powered up, I doubt it is the drive, the second one is doing the same as the last one?
Any comments, it is just a basic M+ drive so I am sure others have seen this happen?

coincident. go to Maintenance->DIAGNOSTIC->Version or somewhere there will be SERVO DRIVES (or SERVO MONITOR)page where you can see alarms history (most recent alarms) .See if there are numbers for Y -axis amplifier. Picture is from T+ , I bet there must be similar for M+

The MDS-(A, B, or C1)-CV power supply may be getting weak or going bad.

These CV power supplies fail just as often, if not more, than the servo and spindle drives...

...yet the alarms will show up on the spindle or servo drive(s).

Not sure why the problem is manifesting on the Y-drive only, unless Mazak / MEAU has the system designed to do that upon the power supply failing...?

...or possibly something with the Y motor/encoder...?

A quote from the ToolCat:

“Power-up issues are often power-supply related.”

A friend/tech took the drive and bench tested it. Some small high voltage device in the drive failed, the same as the one he replaced, it is up and running as I write, with any luck we are good. Power supply would be next?