Tooker check the battery wiring to make sure that the batteries are wired in series ie positive of one battery to neg of the other etc. If I remember correctly the Jet 3 wire from the battery plug into two plugs located in the battery area. Make sure that those connections are good. Also check that the joystick cable is seated well into the 9 pin connector at the rear of the chair. If all of that is good take a digital voltmeter and set it to 200 volts dc plug the two leads into the two outter holes of the charger port located under the front of the joystick. You should read the battery voltage at 25+ volts when fully charged. If you don't read anything there is a bad connection somewhere take the meter and check the individual battery voltage then take a reading at the plugs coming from each battery to make sure you have voltage going to the power module. Take a reading at the rear of the chair at the 9 pin socket neg in the hole in the center and touch the positive lead to all the other holes until you find 25+ volts. If you have voltage at the 9 pin connector then the problem is in the joystick and could be the on/off switch. Let me know what you find and I will try to help further if I can