Last week it wouldn't start because the starter went, so I replaced that and it was fine for about 3 days. Then developed a weak/no start again so I replaced the battery cables that were way past due, and again it was fine for about 3 days. Finally last night it would not start again, tried putting a charger on the battery for a couple hours which helped a little but not enough. I pulled the battery out of my Wrangler so see if that would crank it and sure enough it started strong. Since the parts store was closed and my Jeep is not on the road right now anyway, I decided to leave that battery in it for the time being. Problem now is that I noticed halfway through my drive home that my battery light on the dash was on. The alternator is charging though, because the volt gauge gets noticeably higher after starting the engine. Basically it starts and runs fine and normally now, except that the battery light will not shut off. The only difference now from the way it was originally is that the Wrangler battery is a bit smaller than the Explorers. I think it's a group 56 vs 65. Could that actually make the light come on though? It doesn't seem like the battery should make a difference. Any other ideas??