The error code was 46 (not listed in the manual) which means something is wrong with the power supply. In fact, what was wrong was the generator was f*cked and is currently being replaced. Coincidentally, my trip mileage was 46 at the time so the error code on the dash didn't register as an error code!
Car driving friends of mine can't believe that the new generator parts come to over £800 with VAT.
Having other bits done to the bike at the same time: new exhaust (Beowulf titanium jobby), new OEM rear shock, braided hoses, new clutch and throttle cables, new chain and sprockets, good valet.
Because of this expense, I'll hang onto the FZ1 until 2016 when I'll consider a new bike.