This is probably a Guido question but any input would be much appreciated. A neice left her car (volks) here for the winter. Last fall I put it in the pole barn and after running it for a bit to be sure the batt had a good charge, I disconnected the batt cables and attached a 1 amp solar trickle charger to the isolated battery. Just tried to start it and the battery is flat, dead, not so much as a dash light. Hooked up my "smart" charger and it immediately began to flash that I had the cables reversed; but I didn't, they were correct. Tried reversing them, putting + to - , - to +, and the charger seemed happy. WTH??