AX2850 - One channel is dead?

Hello,

We are suddenly having a problem with our AX2850. This problem occurs with both RS232 and RC commands.

We are using encoders on both channels. The system has been working perfectly for over a year. All settings are the same for both the left and right channel.


THE PROBLEM:
On one channel, when under load (the vehicle is on the ground) the motor will often cut in and out. If we raise the vehicle off the ground and push on the wheel in the same direction as it is being driven, it will pause, jitter, and shake until we stop \"aiding\" its motion. If we do the same thing to the other side, the motor continues to run smoothly.


WHAT WE HAVE TRIED:
We have swapped the motors AND the encoders, and the problem continues to exist only on one channel, therefore we have narrowed the problem down to the controller. We have also carefully checked all of the wiring. This behaviour continues to exist regardless of changes to power settings (current/acceleration limits) and can be worsened by adjusting the PID gains (which are now at their default values)

This problem does not occur when we turn OFF closed loop operation.

Any advice as to further troubleshoot/diagnose/repair the controller?

Thank you.

Ben Creed