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how do i know its my alternator?

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Old 12-02-09, 06:10 AM
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SLEXY94
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Default how do i know its my alternator?

here's my problem.....

i was driving home the other night and all of lights went out right after i turned my heater on.My battery light came on too. i did notice when i hit my remote start before going home, it wouldn't start up. thought it was due to being pretty cold. anyways, when i got home, it wouldnt start up at all, just a clicking noise. The next day i took the battery in to be tested and it was low.Had it charged and the car started right up, no problems. The following day i started the car and it started again.....so my question is....how do you know for sure if it's your alternator?
Old 12-02-09, 06:22 AM
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sc3757
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get your charging system tested. and if your driving or sitting at a light and your batt light comes on most likely its your alternator.
Old 12-02-09, 06:51 AM
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SLEXY94
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how do i get it tested, should i take it off and have it tested? i really thinks its my alternator, a couple months back the power steering fluid was leaking into it.
Old 12-02-09, 07:11 AM
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SH_JZZ30
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You can use a multimeter on the battery terminals while the engine is running to see what it's charging at. It should be around 13.5-14.5 volts.
Old 12-02-09, 07:33 AM
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if it was your battery it wouldnt have started the next day. When i had a bad battery my car ran fine while it was on, but if i left it off for more than an hour, it wouldnt start because it already lost the whole charge, i always had to get a jump from someone. Your battery is fine because it did not discharge over night. This is just my thought though
Old 12-02-09, 07:37 AM
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Originally Posted by SH_JZZ30
You can use a multimeter on the battery terminals while the engine is running to see what it's charging at. It should be around 13.5-14.5 volts.
Do this.

It sounds pretty much like a bad alternator.

Or a parasitic drain. Do you have aftermarket electronics installed?
Old 12-02-09, 12:19 PM
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im gonna bet that it's an alternator. I had stuff like this happen to me w/ my other car and it turned out to be the alternator. A parasitic drain would not have affected the car while it was running.
Old 12-02-09, 12:30 PM
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yeah thats a good point.

I just read the part about overnight the battery was too low to start the car.

Alternator, yo.
Old 12-02-09, 10:37 PM
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thanks, i will start on that, what is that drain that yall talking about
Old 12-03-09, 06:33 AM
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something could be staying on like if you had a charger that is staying on in your cig lighter, or something that is still getting constant power while the car is off causing it to drain the battery, but im almost positive its your alt.
Old 12-03-09, 06:49 AM
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Yeah, its bad wiring that sucks battery power while the car is off.

Like a blood sucking parasite.

Parasitic drain.
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