Andy, further to my last, I should say that I tried and failed miserably to access the ECU. I couldn't figure out how to get into the steel cover. Anyway prior to opening the fuse box I disconnected the battery - just in case. All the plugs and fuses were taken apart, cleaned and reinstated. Be aware of course that you'd need your radio code in order to get that operational again after disconnecting the power. A hair drier aimed at the fuse box would possibly be a good idea - there being no more warm summer days around. I'm now going to make a waterproof cover for the fuse box / ecu box.
Plse let me know how you get on.
John M
September 2010