My wife has an Invacare Buzz scooter - I have got new batteries and i bought a new charger - still won't charge the batteries? any ideas

The Buzz breaks down into four pieces for transport. Electrical connections must be unclipped to separate it completely. It is possible that one of the connections isn't completely clipped together, so my first check (after you have made sure that you have it plugged into a working outlet!), would be to take it apart and then reconnect everything firmly. While you are at it, you should look for any other clip-connections and undo, then redo all of them. Even those that "look okay". Inspect the connections metal fittings for signs of corrosion or dirt that may be causing a high-resistance connection, and clean as necessary. Run you fingers along the wiring to check for any places that my have been damaged, breaking a wire connetion in mid-stream. Make sure the connections to the batteries are clean and free of any corrosion too. Be sure to check the fuses to make sure you haven't blown one, and also push in your circuit breaker. These sometimes trip while charging due to spikes caused by thunderstorms. If you do all this and it still isn't charging, you'll need to open the shroud at the head of the tiller and inspect the connections running up inside the tiller, and the connections going to the PC board located at the very top of the shroud where the thmb-paddles hook into the electrical system. There should be a fuse inside there too, so check that.

Good luck.