the battery lite on my 89 areo star?

You have what is commonly known as a back-feed.

This is commonly caused by a fuse being blown somewhere?

Check all fuses.

Also if you can't find a blown fuse disconnect the Alternator(should be a two prong connector)

If the light goes out it's your Alt.

Good luck

There is a test light circuit wired in there that will make lights come on when you first turn the key on. That lets you know that the bulbs work. After the engine starts, all warning lites should be off. Your owner's manual will explain it to you. When the key is turned to off and the key removed, all lites should be off. Except if you leave the headlites on, and the brake lites will also work. If you have a dash lite staying on after the key is removed, then something isn't turning off. Have the shop check it. But this is not a normal indication that there is some thing wrong with the system that it's monitoring.

Sounds like something with the ignition switch.