We have a Zappy 3 that my mom tried to charge with a wheelchair charger!!! She burned out the pin charger port, which we replaced. The problem we have now is that the Zappy won't charge with the key being in the off position, which is not correct. The charger states charging only when the key is on. The light never goes off so we have no idea how much the unit is actually being charged. It does run, we haven't taken it out on a time test yet. What other damage could she have done and how can we correct it? Thanks!!!