i dont see anything that resembles display faults ,just hours and state of charge in bars.nothing thats shows any kind of numbers at all. as for my experience i m a starter and alternator guy 36 years now, i ve got 3 tow motors 2 propane,and this one electric ( need for it size) i know only real basic on this machine ( not much) i purchased form a customer who does lift trucks had the bug when he had it but cant seem to locate the problem at all. like your honesty to LOL, i ll check to see if he had the ability to hook up a laptop to it,hes an independent so im not sure. it was kinda strage when i just unplugged the circuit board ,turned switch on and off the worked fine for a while now ,no go. buy i may go out in a day or two and work aok. i will locate a service manual asap, i do have a part manual i did locate. i m going to keep packing away. i also did do a direct power relay to activate forward and reverse,worked fine. i do have no doubt the potempiometor in handle is fine and connections i went over pretty well. i just wonder if circut board may be the culprit