Charging light issue
About a month back the battery light started flashing every once in a while, while i was driving. The truck was completely dead on me last weekend in the driveway, so I load tested the batteries last weekend and both batteries were bad. I replaced the batteries and everything had been great until driving home in the rain with all of the lights on, radio, a/c, etc... By the time I was pulling into the driveway an hour later, everything in the truck was dead, doors wouldn't even lock. So i charged the batteries for a good 8 hours this morning to get to a buddies house to change out the alternator.
On the way home the battery light came back on solid for the whole drive. The new alternator was putting out about 13v at idle, and a little over 13.5v at 1500rpm. The same as what the previous alternator was doing. I know the batteries were not fully charged after only 8 hours on the charger.
A few questions....
Could this be a bad alternator?
Will the charge light come on if the alternator is putting out current, but the batteries are still low?
Could this be a wiring / electrical issue, and what should i look for?