Hi...
I just had the same thing happen, after leaving the lights on for 30-45min (too bad the 'your lights are on' warning isn't a bit more forcefull). Anyway, on restart, I was getting blinked at by the airbag light, '53' was the code. After a bit of driving, and a restart, the blinking hasn't returned.
FWIW, I'm pretty sure the battery is at least 2 years old...
Where could I find a list of these 'flash
codes'?
Cheers,
--
Terry McG