On Tue, 16 Jun 2020 at 08:59, Steve Pyke via groups.io
(I've since bought one of those compact jump starter lithium battery packs. Not needed it yet but may do as neither vehicle has moved for three months!)Steve it's possibly too late now but both vehicles starter batteries
are probably now useless, due to being discharged for too long.
You could attempt to recover them by charging them ASAP. Expect to
replace both batteries. I'm not sure how your compact jump start
system works, but I understand that they require a flat battery to be
in a reasonable condition. The jump device probably gives the starter
battery a fast boost so that it can provide some current to help in