Help with a BBS02 display issue

[CaptKirk]

I have a BBS02 that just quit working after a charge. The display is dark, battery is 54 volts fully charged. What voltage should be seen at the 5 pin connector from controller to display from the "P+" wire to the black "Ground" wire" ? I am seeing the full 54VDC at the "P+" pin to ground. Not 5vdc. Any help with this?