Graham, sorry to say that if you do not wish to pay to have your Morgan repaired then it is down to YOU to learn how to DIY, just as many of us have done over the years... As for waggling wires to get it to work, in such a situation, you could be disturbing a poor connection as suggested, or it may have no linkage whatsoever if the fault which could be intermittently resolving it`s self, thus you might as well say a prayer to St Malvern to see if that makes it work..?
Yeah checking earths is a reasonable starting point and usually one of the weak points in a system on an older car that may have been used in all weathers. Basic electrical circuitry is simple to learn enough to understand the various points of contact in order for the circuit to operate as it should though as soon as digital electronics plays a part the game changes.
Ideally someone on here who knows your type of Mog and it`s systems can inform you where the relay is positioned and other possible failure points in the circuit where you can make tests, other than that it is down to you to educate yourself, with a bit of back-up from the TM team..
Good luck..
