Thanks for the guidance - the earth connection seemed solid, as did the starter connections. The Banner was fully charged per my CTEK trickle charger. Dang.
I got a new
jump start Lithium battery this week - claiming a 1000A output start 2000A output peak! 22Ah but 83Wh. Came in a nice box. These batteries have a clamp unitthat plugs into the battery unit, and the battery unit itself. On this one the instructions state you clamp the car battery then attach the Lithium battery, but on doing so the LED display on the clamp showed it to be on standby on ready to charge, and the battery stayed at 100%...
My older puny battery charged to 100% would not start the car, but I tried its clamp on the new larger booster battery... and success! Car started really after 1 turn!
Lesson: always check these boost batteries work! I'd taken the old one through Spain thinking it would boost the Banner into life - a false premise!
