Dead Battery

Good Morning, People Who Know More About Cars Than I Do.

I have a 2001 Subaru Outback wagon. Yesterday I started it and was acting goofy electric-wise; specifically, the radio didn’t work, the battery and airbag warning lights came on, the windshield wipers on the intermittent setting would go intermittent-fast constant-two swipes, etc. I parked it, about 24 hrs ago. Today the battery is dead flat.

Based on my limited automotive knowledge, I suspect the alternator has failed. How close am I?

with out seeing the car i’m shooting blanks. first things first we need to get the battery charged. then advance or autozone can test the battery and the charging system and go from there. also make sure the belt is in place on the alt. and is tight

You could be right but nobody just replaces alternators without testing them so you’re in the further review phase of this problem. After further review, you’ll know a lot more. Based on your limited knowledge, you could become a great mechanic. The more knowledge, the better.

Agree with @BigMarc. There are too many variables here to make a proper determination. You may be exactly right but it could also be a parasitic drain, a bad battery or a broken alternator drive belt. In addition…something could have simply been left on in your Subaru for an extended period of time.

A dead battery can lead to all kinds of odd problems including a failure to jump start. I would definitely test the battery and alternator before proceeding further. Most parts places do this for free.

@DrBones I agree with the others.

Also, replace the battery if it’s more than 5 years old, regardless of how it tests.

Battery is new. I sort of thought that if I’d just left something on, when I ran the car the battery would charge up. If anything the goofiness increased.

Well, o.k., if you guys had said “Has to be the alternator” i would have replaced it myself. As it is I’ll yank it and have NAPA test it. Thanks, everyone!

This is by no means a definitive test but if the battery has any charge in it you could try the following.
Turn the key to the RUN position (do not start the engine) and touch the alternator pulley with the tip of a screwdriver. You should notice a magnetic attraction if the alternator is good.

If you do feel the magnetic pull you might consider a problem in the circuit between the alt. and battery; maybe a blown fusible link, etc.
If you do not feel any magnetism make sure that little red battery light on the dash is operative. An inoperative light will cause the alternator to refuse to charge.

That’s just a backyard method as it’s unknown as to whether you have a VOM and so on. I’m assuming not.

Charged Batteries Won’t Freeze. Dead Batteries Will Freeze.
It Hasn’t Gone Above 32F For A Daytime High Where I Live In Several Weeks.
Ah . . . Spring. Feel The Magic ! (Man-Made Global Warming)

I Don’t Know What It’s Like Where You Live, But If It’s Freezing Weather, And The Battery Really Is Discharged, You’ll Need To Thaw That Battery In Order To Charge And Test It.

The battery and/or car with battery in it, need to go someplace warm for several hours.


I think your suspicion of the alternator may be right on. The wiper problem may be a clue that the alternator has excessive AC ripple voltage which could damage the battery. Most testing places don’t check for a AC ripple voltage problem, they just just check the DC level. Make sure the alternator has less than .1 volt of AC ripple while running around 1,500 RPM and connected to a good battery.