VX1 will not charge and will not switch on.

Hi All
I rode my Vectrix home on a low battery, with the red battery light on for the last mile.
I have done this at times before over the last 6 years to the point where the bike was only capable of walking speed, and it still charged OK. In fact Vectrix recommends doing this periodically.
This time though, there was plenty of charge left, as it was still capable of at least 30mph. I plugged it as normal and left it overnight.
When i got back to the bike, the dash lights were on, but the battery level still showed zero bars.
I cannot turn the bike on though, there is no flashing 'ready', the kill switch doesn't do anything, nor does the ignition key or brake levers. It's like a crashed PC. Can't turn it on, can't turn it off. It's just frozen.
Any suggestions most welcome.
Thanks in anticipation.
Hubcap