Hi, I would check all the wiring as it is very possible you have a loose connection in there. This is a very common issue with these power chairs especially this one;-)
I would pull off each wiring clip and then reseat it to be sure one didn't get pulled out of place.
I will stick with you on this until its fixed. Please rate kindly at time, then you can reach me anytime by replying to this message;-)
Thanks Have a great day!Tech Michael