Spark MAX Client gets error, won't connect to motor controllers

Every time I start up the Spark MAX client, a message appears at the top of the screen and I am unable to interface with any of the Spark MAX controllers:

SPARK MAX server network issue: check that the backend server is running or restart the program

I am plugged into one of my controllers through USB and three other controllers are wired together through CAN. I was briefly able to connect to one of my controllers and update the firmware, however ever since then I haven’t been able to connect. What’s going on?

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Have you restarted your computer since installing the Spark MAX client? I noticed that happens if you have not restarted, and if you restart it starts working.

Make sure you are up to date on the hotfix 2.1.1 client and are flashing the 1.5.1 firmware on all your spark maxes. If there’s still an issue, try reflashing each controller individually in DFU mode or following this guide from Greg.

Having the same issue here, tried restarting and it’s still giving the same error…

Tried restarting for a second time and weirdly enough that fixed it.

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I had restarted it a few times and it was still acting kinda funny, but I did get it to work. Not sure what the solution truly was, though.

My issue is similar, and may be related.
But the problem is when I try to connect multiple Controllers on the CAN line.

The Client application detects the units connected to USB, but the ones connected by CAN only keep connecting and disconnecting every few seconds.

This is the thread I have been discussing the problem on.

I would like to run test on the individual CAN connection with the Command line tool but can’t find it.

Also, I read a lot about reinstalling the drivers manually, but need find instructions.

Any help would be very appreciated.


Ok… I seem to have found the solution my problem.

I was using a 24 VDC Omron switching Power supply which normally does a great job, but must have been causing the problem.

I now have switched to an adjustable Lab power supply set to 13.4 VDC and the problem has gone away.

Since all robots are running on batteries, the problem won’t present itself, but take note that the motor controllers not immune to EM noise and you need a good and clean power source to run them on a bench.

Thanks for your help.

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I had the same issue – it turned out to be an issue with Windows administrative rights. I solved it by starting the Spark Max software with right-click / “Run as Administrator”.