I know there have been a few post's about this but today mine started for no reason at all this morning. I took my standalone pump off to seal a leak and when making sure the oil was getting pumped around i had un plugged the wire to the tank to get a pot for the running oil. Connected it up then it started flashing. Double checked everything and unplugged and reconnected it and its still playing up. Could it be a new tank time?
Try cleaning the contacts in the plug and on the bottle. Clean them up with some grit paper.
Dont worry about this now, just stopped flashing as i was on my way home. God i love old cars.
yeah they seem to repair themselves all the time :P