2014 Tacoma bad alternator, battery or both

Ah the good old days!

 

Update: Thank you all for the advice. I haven't had any issues since the new battery.

 

my 2014 battery just died today with zero warning- truck is 30 months / 44k miles old. my radio would restart over and over. i finally noticed that it would restart mostly when i hit the brakes.

screw Johnson controls - replaced with a brand spanking new JGR kyle bush interstate 1,000 CCA batt. and all is good now.

 

My recommendation is this:

Hook volt meter to battery terminals. Truck off. You ought to see around 12.5 volts, maybe a bit more if you just drove it and the battery has a surface charge. But that's ballpark.

Crank truck and measure voltage. 13.5 at least. If you have that, then...

keep engine cranked and increase the load by turning on headlights and maybe A/C. Still should read 13.5 volts. If it drops off to 12.5 or whatever the battery was reading, the regulator has almost certainly gone south. I have seen em fail where they produce the right voltage (13.5 - 14.5 volts) but very little current, which won't charge at all with the lights on.

If you get 13.5 or so with lights on, chances are good everything is OK with the alternator.

 

man - johnson controls makes interstate batteries - lol