The other day my wife was driving our 04 trailblazer and she said that she heard a loud bang, from somewhere under the passengers feet area.  shortly after that the lights inside and out starteed dimming, and all electrical components were surging and dying.  The batt gauge would fall all the way down to 9 volts.  it is under warranty, but i can't get it in for a few days, has anyone else had this problem?