Battery Lite is dimmly lit when driving around,,but now stays dimmly lit( when key is not in switch),when starting it light's up bright with the rest of the lites, then dims back down..could there be a a ground problem at the alternator or in the dash, my amp gauge says charging fine,has full battery charge when starting.

 

check the charging system voltage at the battery with the engne off and then running.

year engine?

 

2004 trailblazer 6 cyl