I was in the middle of running a job and the laser stopped moving without an alarm or any warning that I could tell. The motors do not react when using the jog arrows nor do they reset when the machine is powered off and back on. The controller screen recognizes the position even when moving the gantry manually. I cannot figure out what may have caused this or how to fix. Pictured is the control board and the stepper motors after powering on the machine. Any advice would be appreciated. Machine is OMTech 60W 16x24.
Both of the stepper driver bricks above the controller show red Error LEDs.
Some drivers have blink codes, but I’d lay a Franklin saying the simplest explanation holds: the power supply for the stepper drivers has gone bad.
The controller still lights up: I think the bottom LED is +5 V OK and the other one shows a Water Protect error (which means you’re not running the pump, which makes sense).
I think the controller will run from a power supply voltage lower than the stepper drivers will accept, so the supply may just have gotten weak, rather than failed completely.
Measure the supply voltage at the stepper drivers and, if it’s not +24 V, that’s the problem.
If it is, there are other possibilities, but let’s start simple. 
Thank you for the reply. Is there a diagram for the controller that shows what each light is? I am running a water pump but have the error turned off (kept alarming even with water flow which is another issue I’m working). Is the power supply for the motors different from the main power supply box? I replaced the main power supply before the picture so still had the issue.
Hidden in plain sight on the back of the controller!
The error LED codes (beyond just “red = bad” and “green = good”) for the stepper drivers depend on the exact model-number-and-letters, which is generally printed on whatever side of the driver case you can’t see without getting it out of the laser.
That’s the shiny metal box below the controller. The green LED visible through the perforated lid and the controller LEDs show it’s working to some extent.
CAUTION: Two of the unprotected screw terminals over on the right side deliver 120 VAC power to the supply, so be careful when you’re poking around in there with the machine turned on.
The usual machine has a 24 VDC supply, sometimes with an additional 5 VDC output, all present on the screw terminals. Check for loose screws and bad wire crimp connectors; don’t assume the factory did it right.
The current rating for that supply is generally less than all the other parts of the machine require (because hey it’s cheaper), so it runs at or beyond its capacity and tends to fail early, sometimes by producing low or erratic voltages under load.
The only way to be sure (after checking for wiring problems) is replacing it, which requires matching the output voltages and, if possible, getting a higher current 24 VDC output.
Thanks again for the info. Are there fuses in the “shiny metal box” that could have gone bad/blown during the running of a job that can be replaced or am I looking to have to replace the whole box?
There’s a line-voltage fuse, but it’s typically soldered in place: when it blows, something has gone badly wrong. In any event, your supply is working almost right, because the controller is all lit up and seems happy.
They’re cheap (on the order of $30 - $50) & readily available (beware bottom-feeder Amazon sellers). You must extricate it from the machine to find the sticker giving the voltage(s) and current rating(s). Also measure it to get one that’s about the same size; the widths are mostly standard and you have some wiggle room for the length & height.
Now, to be honest, I do not know the supply is defunct, but both stepper drivers are complaining about something and the only thing they have in common is the power supply.
If you can measure the output voltage at the supply and at the stepper drivers, that will be informative. The real problem seems to be maintaining that voltage under load without browning out, which is probably what the steppers are complaining about.
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