Jumping another vehicle. Cable attached to target vehicle. neg cable is attached to neg pole on my battery. Letting loose of the positive cable, it swung over to my neg cable. Big spark. Drove it home with red battery on the dash. Next day I only get a click. Both batteries individually check out at 12v. Still clicks.
When truck not been started between 4-5 days try to start won’t start installed 2 new batteries 2 months ago after boosting leave truck running for 15 minutes then starts without boosting