will unplug it and see what happens on the ceffy
after u jump start it remove jumpers from hillux.if alt is working it should be at 13.+ volts 13.6/13.9 etc
using same battery that u put the wrong terminals on?
could have blown one of the cells inside, i have had a case where a bat was showing 12v+ and not starting only to find battery was gone, fixed with a new bat