The other day I started my 2004.5 and drove 5 miles to a Dr. Appt. Right after starting I noticed my dash alert said "check gauges". I did and my charge meter was down to zero (aka 8v being far left). I drove the 5 miles in the daylight with no issues. The meter never came back on. After appt, 45 min, I started the engine with no problem and the meter was working again showing 14v. Hasn't happened again in 3 more starts, with good voltage reading. So is this a warning my alternator is going? Or what should I check for an intermittent problem of this type?