Reverse Beep During Charging, Charger Disengages

[ksquared]

Hi there. I have an 2000 EZGO PDS. Was driving the cart one day and received three beeps and a lurch before it stopped working. Reverse beeper still worked and cart rear tire would lurch ever so often but wouldn't go and the reverse beeper would come on when charger was plugged into the cart. Replaced F/R Switch, Motor, Controller, Solenoid, Microswitch and Ignition Switch. Cart now works, but still having the issue with the reverse beeping sound when the charger is plugged in. Appears there is some type of surge and can't locate the wiring issue. Unplugged one of the reverse alarm wires and of course the beeping stops, but when plugged in the charges engages and the needle moves and then very quickly returns to 0 (essentially stops). Any ideas on how to address this? Thanks in advance