ERC040AFN is a 4 wheel sitdown 36v counterbalance.
i presume the fuse it is blowing is the control fuse in the fuse panel? then start back probing till you find the short, it's either wiring chaffed and grounding or a bad component or something along those lines.

I highly doubt it's a battery cable, if it is that, you will definitely see sparks and fire and smoke so finding one of those cables shorted should not be too hard. ;o)

take a very good look at the battery cables.

if one of the cables is cut, has exposed copper, and maintains contact with any metal part of the pallet truck, that would be one reason for blown fuses.