Difficulty Getting the Pulley to Move Down (Suspicions of a Programming Issue)

[MegaQueen]

For our pulley we are using one motor that is programmed to move forward to lift and backwards to drop. It works fine while lifting, but the motor chokes while dropping. We tried to connect the motor directly to the battery and it worked perfectly both ways. But once the talon was connected to the power distribution panel, the pulley no longer flawlessly dropped. So now are suspicions have turned toward the programming. Do the talons understand the negative voltages/inputs to reverse the rotation of the motor? Or is there another possible way that this may be fixed?

Thank you!