if everything appears to work except no forward or reverse, I suggust you check the following,
horns etc require very little power so that does not mean the batteries are very low , not enought power to drive , the normal clue here is a click, any beeping or flashing led ?
check under the seat as there is a reset switch , make sure that's it working okay by pressing it,
if you cannot push the scooter in freewheel and you're sure the brakes are released then it's the gearbox that is preventing freewheel mode.
Regards
Gewiz
gewizrepairs.co.uk, December 2009