2007 star ev issues

[Bowman_7510]

I’ll try to shorten it down for everyone. About five years ago my grandparents Boy are used our golf cart off of a couple down in Florida. The golf cart ran great but never had working headlights or taillights. Fast forward four years my dad purchased my grandparents house and golf cart off of them due to them getting older and not being able to travel south anymore. My dad really wanted the headlights and tail lights to work so he brought it to me and asked me to take a look at it. I tried many things but could never get them to work so I purchased a universal wiring kit and just re-wired the light assembly along with a new voltage reducer and finally got them to work. After finishing it I drove the golf cart around a little bit and everything seem to work just fine, I loaded up on a trailer and took it to the campground for him and the batteries were dead To a point the charger wouldn’t acknowledge them so he hooked up a car battery charger to get some juice to them so they would kick the charger on. I’m not exactly sure what happen from there but now the voltage meter in the dash flashes back-and-forth that the batteries are dead even though it’s getting 48 V up to there and the battery pack itself is reading 48 V. Also when you put the golf cart in forward and or reverse it will only go about a mile per hour and then kicks itself out to where you have to decompress the accelerator and then reapply it to get it to move but it will not go any faster than about 2-3mph all while saying the batteries are dead on the gauge. Anyone ever heard of such a thing? I have unhooked, cleaned, and rebooked up every wire I can possibly get to and still nothing has changed.
I’m at a loss for ideas now. Any help would be appreciated. Thank you!!

Ryan