Hugo
I had the very same issue on a trip to Scotland recently. I disconnected the battery terminal, left it for 2 minutes and that solved the problem. It was a pain because you could not see the mph reading and the speedometer is useless!
The following day we had the little yellow submarine sign appear, looked in the handbook and it said "check the engine". Well I had a look and the engine was still there so we carried on. The following day it dissapeared and things have been normal since. It's a Morgan, what do you expect.
Sir P
