Hey gang, new here and first post. I'm pretty stumped right now, though. I have a 2015 Frontier V6 and am having issues with my battery/alternator/something in between.

In January this year, my alternator failed and I replaced it with no issues other than the discomfort of working on a vehicle in January in NJ. Changed the serpentine belt as well while all was taken apart. In terms of electrical, everything was fine until yesterday. Yesterday, I noticed my battery was showing low and not charging while running. I figured I'd look at it this morning. This morning, she started and I got about 6 miles down the road before the battery Guage quickly dropped and I lost power to the engine. Not all of the car, though. Power steering, radio, phone chargers, A/C all worked fine while i coasted to a side road, fortunately near our local auto parts store. It at this point would not start. I was planning to get a battery here anyways as it was testing low. So, I bought the battery and used that charge to get back home where I have tools.

I took apart the truck and pulled the alternator again and took it to advanced auto up the road where they have the alternator testing machine. On 3 tests, it tested good. So I swore a bit as I was convinced I just got a bad alternator and took it back along with a tensioner assembly and serpentine belt which I replaced after noticing play in the tensioner and assuming it could possibly be slipping on the alternator pulley, perhaps. Put it all together and she started up. Let her run while I was in taking a shower and came back out to a dead battery again.

So having run through the solutions my brain has, what do you all reccomend as my next step? I'm a little stumped. Thanks in advance to anyone who takes the time to help!