you do have cables that run under/beside the battery to the drive motors from the controller and contactor panel in the back.
Thanks for correcting me about the short being only on the battery meg cable to the case of the battery, my misunderstanding of what was said.
as this is a 2 motor system, there should be 4 directional contactors, right and left pairs of forward and reverse, and they should pull in, as pairs, if the rear wheel is in the straight ahead position.