Hey guys,

I was polishing/waxing my car today, and after i was done, i went to start my car, and all i heard was a click, then i see all the dash lights start to fade. So I try again, not even a click this time. So now, i know the battery is dead. Since i was at my buddy's place, i jumped it off his car and drove home. I thought maybe it's just that the battery is low, maybe I started the car too many times to move it around that day. So I drove a good 20 min, hoping it would charge up.

When I got home, and I tried starting my car, sure enough, it wouldn't start again. So this leaves me with 2 possibilities (if there are any more, let me know). My battery is dead, or my alternator is dead. What do you guys think? I can't take it anywhere to test becuase it's 10pm and all the stores are closed

 

Battery sounds dead to me.

 

if you were able to drive for 20 minutes, its probably your battery, but best way to find out. get car running and hook up a battery meter, should read like 13.9 or along those lines, without any lights or stereo on, if it reads less than 12 with car running itll probably be altanator.
but keep in mind bad batterys can drain power from a car. but its kinda rare
what i like to do when i have similar problems, steal my parents or friends battery and try it out.

 

When you jumped the car did you leave it running for a few minutes before shutting it off and trying to start it on its own? Also if you have a bad alternator that could cause a bad battery I believe.

 

possibly both.

 

If you were able to drive that far then I would say that the alternator is probably doing its job. Before replacing the battery be sure that the battery terminals are clean. I prefer to scrape the i.d. of the terminals with a pocket knife and scrape the battery terminals with a knife to remove the hard oxide layer that often builds up. I have found that the wire brushes made for this purpose do not do a good job .

 

yeah, i left my car running for a while after i jumped it and then drove it for 20 min. w/o turning off the car, i figured if it was my battery, it should've recharged it already.

i hooked up the battery to a battery charger last night, it started out at 0V now it's back up to 12V....if it was the battery, it wouldn't do that right? well i'm gonna check it out now....bring it somewhere to actually get it tested...

 

exact thing happened to me when i drove to the store once. click, then nothing the next time. all i had to do was clean the battery terminals they didn't look dirty until i put that little scrapy thing on there and it started to shine.

 

hmmm, maybe i should clean them....

but i found out the problem, it was the alternator, got it tested and there's no voltage coming out of it....damn, i was hoping it was just that battery, that would've been cheaper

 

pm silverrotor to upgrade to an FD alternator.

 

You were able to drive 20 minutes off the battery? Your pretty lucky then. Most cars wont run that long of battery alone. Especially at night.

 

yeah, i didn't turn my headlights on, or radio or nething, running the car itself doesn't take that much batteries right?

 

you wouldn't believe how hard it is to find a friggin alternator for an s5....i got 2 yesterday, the first one, the pulley didn't fit, the second one had the wire harness coming out of the back making the wires of the harness push against the engine block itself, yeah, i don't think that's a good place for it. I just picked up my third one, I haven't put it in yet; but I already noticed that the stub where the ring terminal is connected to, (I'm guessing it's a ground of some sort), is sticking out of the back of the alternator, it's pretty close to the engine, maybe less than a centimeter away. That should be alright, right? worst case scenario is that it melts the rubber shield over it, right?