have stripped out all the split chargs stuff etc and now have a single battery, took the battery from my series 3 and connected it up to the +pos first when i went to connect the -neg got some nice sparks, not the fearce dead short but enough to...
Definitely go back to the single factory set up , use the wiring diagram and go through a process of elimination.
See if any of the wires are melting or extremely hot to touch
out pottering around today and visited a friend, was in for a cuppa and a blether about 2 hours in total, came out to landy turned key and nothing, completley dead, stuck jump pack on her and she fired up straight away, drove home about 5 miles...