New S3 Machine Stopped Responding Mid-Job

Hi everyone,

Just received and assembled a new Shapeoko 3 XL. The machine stopped moving mid job. Carbide Motion reported ‘Machine Stopped Responding’. The last few log entries say “GRBL Watchdog Expired Set Machine State: NOTCONNECTED”. I had to quit my job.

Does anyone know what might cause GRBL to time out on the connection ?

Is this connection between the machine’s control board and the motors ? Or is this between Carbide Motion and the control board (i.e. USB) ?

I recorded the machine position of my job’s zero-point (origin). Is there a way set the machine position back to this point ? Manual jog or G0 command ?

After some debate, I routed the power wire for the router through the guide chain with the Z/X motor wires that is mounted to the X gantry. Is this causing interference ? I noticed some install instructions zip-tied the router power cable to the motor cables, so I thought it might be ok.


Interference has been an on-going issue.

We have some information on it here:

If the recommendations there which you’re comfortable doing don’t help, check in w/

Hey Chris-

That error message is something new that we added in the latest release. Basically, if the embedded GRBL controller doesn’t respond within 2 seconds (unless it’s homing) then Carbide Motion will error out and disconnect.

Was the machine moving when this happened or was it stopped?
Are you running our GRBL or did you reflash it on your own?

The zero point is also recorded in your PC so the zero should be retained even if the machine reset. You can go to Jog, then Rapid Position, then click “Current Offset X&Y” to check that it was saved properly.


Hi Rob,

Thanks for the quick reply!

I can’t say definitively if the machine was moving when the disconnect was reported by CM, or if it was stopped. The job is 14 hours long, so I went to check on it (I watch via VNC from my workstation using a web cam) and noticed that CM reported the error. At that time, the machine was stopped.

I managed to home, then use MDI to issue G0 command to the coordinates for the job 0 point that I recorded manually (screenshot of CM Zero Screen). I started the job from the start.

I have a log file of the botched job. The last move to be executed was N7136, so I will wait until the new job’s log gets close to that, then I’ll turn on the DW611 and the dust collection system to resume where I left off.

Given I know the line it stopped on, is there a way to resume from that line in the g-code file ? Would it be possible to find the line (NXXXX) in the g-code file using an editor and then manually edit out previous commands ?

Forgot your other question:

I have not reflashed anything. I’m using the controller out of the box. Whatever was flashed at the factory.

Well, my wire management was definitely sub-par. I have since adopted all of the separation and management guidelines suggested, short of installing any new components (toroids, beads, shielded USB cables, etc). I will look into these things, but for now I will see how it goes.

I see it recommends that the router power be routed to the side opposite of the controller box. I will do that later, but for now see if I can squeak out my job. Fingers crossed.

Hey Rob,

I paused the machine while re-running the job and while it was paused (stopped) CM was disconnected as before. So I guess the answer to your previous questions is that it does disconnect when stopped.

Bit extreme, I recommend going to your boss and asking for your job back :wink:


Lol. I have had my share of disconnects. Nothing is more detouring as a beginner in the CNC. As a newcomer it isn’t something that is just known…

#shapeoko is about a community, and we like to help our own.

Limit switches. Number one productivity upgrade.

Contact support. Seriously @edwardrford and his team will take care of you. Best support I have ever dealt with. Better than inventables.

I only had it happen one time, good thing is my software re-connected with the soft kill button and I was able to figure out which line it was on and create a new g-code file and resume from that line essentially. After that, I told my wife she is not allowed to use the vacuum cleaner in the living room when the machine is working lol! Honestly that was the only thing that made it disconnect, she hasn’t run it since and I have not had any disconnects since either.

Hi all. Thanks for the info!

After following best practices for cable management, I have not had the disconnect issue. Power is now sourced from 4 different house hold circuits, and all power cables are kept clear of the USB cable and control board.

The router power cord is still inside the cord guide/snake with the X and Z motor wires, but no issues yet.


I just had this happen to mine twice in just a few minutes time. This is the first time I’ve had it do this. No idea why. One was while in the middle of a job, the second was after the job was finished and had went thru homing sequence.

Just happened AGAIN mid job…what the heck is going on?! I’ve ran a few dozen jobs, at least, so far without this happening. What is the culprit here?

List of things to try here

…AND AGAIN. Different file altogether. No other electrical components are running. Dammit.

I am experiencing this problem after using my new machine without issue for the last 2 weeks. Did anyone find a resolution?