Not starting, Battery Light On, Low Voltage
 

As the title says... my truck hasn't been starting on occasion. The battery light has been on recently, but it starts fine when it wants to. I took it to Advance, and they tested both batteries as full charged (great cca's). However, it showed as low voltage. The guys suggested the alternator (which we both agreed since the battery was still charged fully with great cranking amps, that probably wasn't it) or the Voltage Regulator.

I don't want to just start replacing sensors if that's not it. Could I get some quick help, please? I can't have it not operating fully, but I don't have the funds to just replace and try it out. Is there anything else that I may want to possibly try beforehand. Terminal posts look good, and I have no reason to believe that the cables are messed up. Thanks for the quick response in advance. I know you guys are the greatest. Thanks again.

Actually, I'd think you should get them to bench test the alternator, for the very reason that the battery voltage is low.

Sounds like Barebones is on to something, Bench testing the Alternator would be a great place to start. Or~~Instead of going to Advance Auto.The (Dealer) has quite the "Better Trained Eye Mechanic" for that type of diagnosis. I am sure cash is an issue, as with most folks these days but, the Dealer doesn't have to "fix" the vehicle either. Just a quik diagnosis, then tell 'em you'll see them another time. Go to Advance or Auto Zone and get your fix! For the aggravation of Advance making the wrong diagnosis on this type of problem, and with the level of difficulty with this type of problem...Go where people know the "BEST"....Trust Me.! The Dealer may be a couple bucks more to find the problem, it will be worth it in the end.! { Hope this helps? }