purchased 2000 venture van. It was advertised with bad battery. I jumped it, test drove and decided to buy it. I drove it home with the old battery in place. There were no issues. No panel warning lights, no problems with trans. Car ran great. After getting home, I installed a new battery reinstalled fuseblock. When I switched the key on, I had a ABS warning light, Trac Off and Airbag light. These stay on constantly now although the brakes seem fine and the trans will shift hard sometimes, sometimes not. Everything was fine before the battery change. Could I be missing a connection. The battery connector to the fuse block spartks when I remove it and reinstall it. It didn't do that initially either.
My car has 260000 miles.
My car has an automatic transmission.
You may have damaged the systems when you disconnected and connected the positive cable to the fuse block last and not using the battery ground. I would recommend disconnecting just the battery ground and then leave it off for ten minutes. Afterwards, reconnect it and see if lights go off. If not, then have a certified mechanic, like one from YourMechanic, diagnose the warning lights and scan the systems to see if they were damaged.