bad alternator,bad battery or do i have a drain?

kenjiw · Nov 16, 2013

So this recently start happening where during the week i would notice that when going to start my car it would feel like there was not enough battery. And then a few days of that, my car wouldnt start it would just make a buzzing noise when cranked so i jumped started it and it cranked right up super strong. And then 3 days later samething happened where i needed to jump start it again. And yesterday night while driving, my lights dimmed,battery light came on,radio shut off and anti-lock light came on.

My guess is a bad alternator what do you guys think?

rydereclipse · Nov 16, 2013

Check your battery when the car is off with no accessories on......sounds like you have some kind of drain.

gusu · Nov 16, 2013

Since your lights are dimming while driving it's most likely your alternator. It could possibly be your battery but that isn't likely.

The reason I say this instead of some kind of draw is because your alternator should be able to push out enough current to keep your car running properly. If you had a draw on the battery the car would still get a charge from the alternator so it wouldn't be dying.

Talonman86096 · Nov 16, 2013

With the dimming it does sound like some kind of alternator issues. But the buzzing you heard was it coming from inside or did it sound like it was under the hood? I had a similar issue once and I know the starter relay will make that kind of noise if it has popped out or is bad.

born2race · Nov 16, 2013

What is your voltage at idle??

kenjiw · Nov 16, 2013

Talonman86096 said:
With the dimming it does sound like some kind of alternator issues. But the buzzing you heard was it coming from inside or did it sound like it was under the hood? I had a similar issue once and I know the starter relay will make that kind of noise if it has popped out or is bad.

The buzzing is coming from inside the car and i do not have a multimeter to check the voltage of the battery and the battery is less than a year old. Not to mention i did install 2 Gauges where they stay lit up when driving regardless whether its night or day as long as the car is on but i dont think too little gauge lights are gonna cause a battery drain?

gusu · Nov 16, 2013

The gauges could be causing draw, but there isn't any way your gauges are causing your lights to dim while driving unless you have a crazy as short. A short to the point where I don't see how your car isn't catching a fire, while it could happen most likely you'd either burn a wire or blow a fuse.

Buzzing with a low battery from not getting enough charge from the alternator will cause a buzzing or clicking sound while cranking. My old starter would make a humming/buzzing sound but my new starter makes more of a fast clicking sound when the battery is drained.

I have no splash shields on my drivers side so my alternator dies about every couples months so I am fairly used to seeing these symptoms.

Talonman86096 · Nov 16, 2013

Just check out the starter relay and make sure it's ok. I know that was a quick and simple fix for me me once before. It's on the passenger side center console area behind the radio and such. I'm far from a "wiseman" on here but I always try to start with the easier possibilities before diving into more in depth things LOL

. I know with the dimming and everything you may have some other issues with the alternator and drain somewhere but doesn't hurt to check.

Madrox · Nov 16, 2013

hate to hijack this thread but i had the same issue..with a question:

For me it turned out the internal foot lights were always on, that was my draw. I couldn't ever see it in the daylight and it wasn't until one night that it was obvious. I haven't had a chance to troubleshoot it so i yanked the appropriate fuse.

Got a multimeter and at idle my voltage is 12.4, obviously not enough to charge the battery. I recently had a bunch of work done to the car is it possible that something was knocked loose (ground, wire) or a fuse blown..or is is obviously the alternator?

side note: Went to several part stores (Autozone and one other locally) and both told me "when your car is running take off the negative battery terminal, if it dies its your alternator" I know this is NOT a good idea as what I've read is with modern cars this will possibly fry your electrical system due to voltage regulators, etc.

Phantom DSM · Nov 16, 2013

Madrox said:
hate to hijack this thread but i had the same issue..with a question:

For me it turned out the internal foot lights were always on, that was my draw. I couldn't ever see it in the daylight and it wasn't until one night that it was obvious. I haven't had a chance to troubleshoot it so i yanked the appropriate fuse.

Got a multimeter and at idle my voltage is 12.4, obviously not enough to charge the battery. I recently had a bunch of work done to the car is it possible that something was knocked loose (ground, wire) or a fuse blown..or is is obviously the alternator?

side note: Went to several part stores (Autozone and one other locally) and both told me "when your car is running take off the negative battery terminal, if it dies its your alternator" I know this is NOT a good idea as what I've read is with modern cars this will possibly fry your electrical system due to voltage regulators, etc.

Do Not try removing negative terminal while car is running. Check Your 80A fuse for alternator and check if 2 wire connector is hooked snug on the alternator. Also the wire on the B+ termainal of the alternator could be loose check that. Voltage should be above 13.5 at least on idle. Turn on headlighs wipers, etc and rev motor to 2500 rpm, it should not fall below 12.6 or so.
To the o.p. The symptoms you are having point to a bad alternator if you have checked everything in your car, it should not dim or radio shut off while driving. Check your voltage at idle as well, what does it show?

Petergeralis · Nov 18, 2013

Do a parasitic drain test, get a meter that reads milliamps and disconnect the positive side of battery. Hook the meter up in series with the cable/battery completing the circuit. Now with no electrical loads on see how many milliamperes you are pulling. Normally should be any where from 50-120 milliamperes is allowable. If higher, say 400-1/2 amp there is a drain. To isolate it, start pulling fuses to see when drain drops. Also unhook alternator power wire, and starter hot wire. Don't forget to check any aftermarket wiring that's installed.

dans95dsm · Nov 18, 2013

might be the alternator isn't giving enough charge,
my alternator died and it drained the battery,
even with a jump it drained it quickly

Liltazz803 · Jan 16, 2014

Sounds like a bad alternator

First check your wires because the connector might be rusted and broken i just changed mines because mines was doing the same thing

98eclipse2015 · Jan 12, 2016

Petergeralis said:
Do a parasitic drain test, get a meter that reads milliamps and disconnect the positive side of battery. Hook the meter up in series with the cable/battery completing the circuit. Now with no electrical loads on see how many milliamperes you are pulling. Normally should be any where from 50-120 milliamperes is allowable. If higher, say 400-1/2 amp there is a drain. To isolate it, start pulling fuses to see when drain drops. Also unhook alternator power wire, and starter hot wire. Don't forget to check any aftermarket wiring that's installed.

Ya I'm going to do that once I get the voltage back up. I got the car from kid and he really didn't say what he all did on the car I was told to test the alternator having gottin around to it just yet

The Top DSM Community on the Web

bad alternator,bad battery or do i have a drain?

kenjiw

rydereclipse

gusu

Talonman86096

born2race

kenjiw

gusu

Talonman86096

Madrox

Phantom DSM

Petergeralis

dans95dsm

Liltazz803

98eclipse2015

Similar threads

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds