One side of drive train not turning

Hi rookie team last year here. We have been updating our robot and have ran into a problem. Our right wheels ( we are using KoP drivetrain) turns while our left does not. We are using VictorSPX’s, and we have two controlling four motors. We have checked the wiring and it appears to be all good so we think it is a coding issue. We have occasionally gotten this error in the drive station but not every time. ERROR 1 DifferentialDrive… Output not updated often enough. edu.wpi.first.wpilibj.MotorSafety.check( Heres the link to our code on GitHub, its very basic we just have a base. Any help would be appreciated, Thanks in advance.

When you’re running the motors, check the lights on the victors. When nothing is happening, they should be flashing orange, but when going forward they turn green and going backwards they turn red. Make sure you’re not running the motors against each other either.

They were just flashing orange and the motors aren’t running against each other. The motors on each side are controlled by one motor controller.

How many motors do you have on each side? What types of motors?

We have two CIM motors on each side in a gearbox

We had an issue very similar to this this year. While we didn’t get an error like you did, half our drive train wouldn’t turn occasionally. We actually found the issue to be a short in our circuit. The way our breaker was mounted, a corner of some tube aluminum was pressed against the wire, actually cutting into the wire after a while, causing us to short and lose half our drive train. Shorts like this happened in multiple different ways for us this season, so even if you checked all the wiring, check again. Pull on connections, check sharp corners, make sure there is no exposed wire. We had Anderson connectors actually melt together due to a short, that we didn’t even notice at first.
This very well could be a coding issue, but dont count out electrical until you’ve checked, and double checked, everything.

1 Like

Per 2019 R37, each motor controller should only control one motor. While this might not be the exact cause of your issue, I would definitely change this soon. I would also recommend double checking the wiring.


We are using this robot for demonstration not actual matches, but thanks that will help us when we make our competition robot.

A simple way to help diagnose the issue is to disconnect one of the motors on each side. I don’t know if it may be the starting surge current of 2 CIM motors is causing the controller to go into an overcurrent fault condition. That is a common self-protection feature in many motor controllers.

If the side that was not turning starts working, swap the connections to the disconnected motor. There is a small possibility you have a shorted motor.

Alright thanks will do soon

The wire crimp is janky. Me and Nate fixed it and that’s why it wasnt sending a return value.

This topic was automatically closed 365 days after the last reply. New replies are no longer allowed.