[Kevin Sevcik]

It sounds very much like you're hitting the overcurrent fault in the jags. Whipping a motor from full forward to full reverse is going to pull an enormous amount of current, especially if there's any inertia attached to it. A CIM motor at stall pulls 133A. A CIM motor suddenly whipped into reverse while running full forward will pull darn near twice stall current until it actually stops and turns around. The jags have a two second, 60A current limit. But I'd bet it's significantly shorter is you're pouring 200A through the poor thing.

So, for the benefit of your jaguars and your entire drivetrain, you should probably either coach your drivers to move a bit slower, or put an acceleration limit on your pwm outputs.