Many thanks Zumad. That might well be the DPPM unit that is mentioned in the battery system menu.
Well we may give that impression @bar2 , but I hadn't got a clue until I Googled DPPM. It seems to manage the charging of the battery so I guess that DPPM is the same as a CMU, but spelled a bit differently. Its only 4 letters different !
And really, if I I had aspirations of being technical, I could probably make a start by not frying the battery in the first place.
Given that info, it might be worth throwing good money after bad and buying a new battery. But I'd then have to solder that in too. Hmmm. I wonder if one of my soldered joints moved while it was cooling and has gone 'dry'.
See my update to post on 6th December - a few posts back.