i just had my alternator go bad and that is what came up for me. You might check your serpentine belt first just to make sure it’s still there...a bad tensioner will make it snap. Then I’d take it to autozone. They’ll confirm a low charge if it’s the alternator. It’s a very easy job if you are at all mechanical. Plenty of YouTube videos on it. It’s three bolts that fasten it to the truck and two electrical leads. Took me less than an hour to do and a rebuilt oem alternator was $80 on eBay. I figure if it lasts a year, I’m still in better shape than paying the $900 (cough) the stealership wanted for a new alternator.