My battery keeps draining

[GiovanyS214]

Whats up guys,

So I have a 2000 ford ranger with battery issues... Since i bought it, (bought it 4 months ago) i never had any kind of electrical issue with it until now. Whats happening is that i left my phone charger connected to the cigarette lighter port overnight and it drained my battery. Its been a few days now and even though ive jumped the battery a handful of times its like the battery cant hold a charge.. I took the battery to autozone to get the battery checked and they said it was fine. They charged it up for me (supposedly) and when i hooked it back up the truck still didnt want to start, sounding like the battery was indeed dead again! So i got a jump from a jump kit from autozone and it started right up. Thinking that it might be my alternator, i got the associate to test it as well with some kind of scanner, to which he said everything looked good and everything passed. So now i got home and i turned it on and off a few times and it turned on no issues but like a few hours later my battery died once again! Whew! Can anybody give me any insight to what the problem is or point me in the rifht direction? Im honestly at a loss right now and i cant figure it out! Can anybody point me in the right direction????

 

[Bgunner]

Bad connections is the first thing I would look at. Be sure the terminals are in good shape and properly tightened.

Next would be have a different place test the battery to be sure the battery is indeed good as all other tests require the battery to be good to do the tests properly.
My truck did the same when my phone charger was left plugged in and the cause was the battery was bad.

Next step would be to do a Parasitic Draw Test, this test must be done with a 100% known good battery https://www.therangerstation.com/tech/parasitic-draw-battery-test/
This test will tell you where the voltage draw is coming from if there is a draw killing the battery over night.

 

[Curious Hound]

Sounds to me like you need a new battery. You discharged it too far with the phone charger plugged in all night. A new battery may survive that a few times. But an old one will not.

I would recommend putting a charger on it for 24 hrs. Disconnect both cables from the battery. When you disconnect the charger, measure the battery voltage. Then keep measuring it periodically for the next few hours and see if it holds a charge with nothing connected.

 

[GiovanyS214]

Update: turns out i do have a bad battery. Took it to O'Reilleys and they confirmed it. Thanks to all ya'll.