1998 F-150 (5.4L). Battery died, just before it died the Battery Warning light came on. Replaced the battery and the light went out. Truck sat "overnight" and upon restarting this am the light came back on and remains on. The Ammeter does show a "positive" charge..(i.e.; the needle has moved toward the 18V level. Any ideas?

 

Jump it off, roll to Autozone or Advance, and have them check the altenator. Sounds like it's not charging properly.

 

No need to jump i...the battery has plenty of juice. It is just the loght won't go off...it (light) never came on until the battery went dead (which has NOW been replaced). I will go by an auto parts center and see if they will check the charging system. Thanks for the tip.

 

If the charging system is okay, I don't know if the battery light must be cleared with a scanner. I've never run across that problem... Anyone else know that naswer to that question?

 

I will know if the charging system is working properly after I have it checked. As of now the ammeter needle (dashboard gauge) is showing a positive charge . . . but they also call those idiot lights don't they?

 

If the voltage regulator on the altenator is bad, that could be why the ammeter is so high. That's also bad for the battery. Have it checked, and good luck.

 

Try starting the truck, put it in neutral and shut it off and then start it back up. I know this clears the abs light so it might work for this, but make sure you don't have a problem with the alternator

 

Problem resolved. Bad alternator...everything works fine now. Thanks to all who have made comments.

PJ in San Diego