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changed alternator & battery still losing power

Old 06-01-09, 02:32 PM
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choithew
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Default changed alternator & battery still losing power

My car loses power gradually and then eventually dies from not enough power to work the car. I changed the battery (today) and the alternator (yesterday), and checked the fuses.

First thing that dies is the radio, then the headlights, then the car, any ideas of what else it could be? i have a power steering leak, some may have gotten on the new alternator, would that kill it instantly?

The alternator is worldwide from advanced and have heard that sometimes those can be bad when purchased from advanced, anyone else know anything about this? (it has lifetime warranty so i can exchange it if its bad but it takes 48 hrs to get a new one.

It feels like the alternator isnt working at all, i think i just run off the battery till it dies and the car wont run. I would think if the alternator was working i would at least be able to keep the car on.

If you guys help me out I'll get some cool vids of drifting on dirt roads!!
Old 06-01-09, 02:46 PM
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Ali SC3
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is it a 300 or 400. the leak on the alternator is mostly for the 400's i believe.

my 300 was killing batteries and It had a hard time starting up. new alternator didnt seem to do anything. turns out it was the starter on its way out, so when I went to crank it would turn real slowly, and that would kill the batteries. I took apart the starter and knocked out a bunch of debris and dirt from it, and it now starts on a dime and the battery isnt dying anymore, and everything works correctly.

if yours doesnt have any trouble when starting but just afterwards I would suspect that either the alternator isnt cranking out the voltage, or your battery isnt taking on the charge. check your fuses and stuff.
get a multimeter and make sure you have at least 13v with the car on, or
Advanced auto can test your alternator very easily with their battery tester.
also new batteries sometimes sit on the shelves for a while and need to go through a few charge cycles before they start to behave. that all i can think of for now

Last edited by Ali SC3; 06-01-09 at 02:49 PM.
Old 06-01-09, 03:31 PM
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choithew
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thanks for the info

its a sc300

it doesnt have a hard time starting until the battery is dead obviously... the car will die while driving, acting like the alternator isnt doing anything. I checked the fuses, guess i'll have to take the alternator back off and take it to advanced to get tested, thats the only thing i can think of. But its the same symptom as before i changed the alternator, so maybe its not the alternator, i'll go through the fuses again, only one i really checked was the alt 120 fuse.
Old 06-01-09, 04:45 PM
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turbodremz
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check ALL your grounds, and the positive cable to be sure nothing is loose. my old s13 hatch did exactly what you are describing, and turned out my cables were bad.
Old 06-01-09, 06:08 PM
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choithew
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i'll check the grounds too. i drove my car to advanced turns out that the alternator is dead. so i'll get it by tomorrow they said... keep you guys updated. videos will come
Old 06-01-09, 06:59 PM
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Amini9
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just putting it out there, maybe an electronic is drawing too much power.. keyless entry??
Old 06-03-09, 12:09 PM
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choithew
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well turns out not to be the alternator, i took it to advanced today b/c they finally got the new one in, tested mine (on the tester this time) and it passed so they wouldnt exchange it.

so if the alternator works and the alternator is not charging the battery, what could it be?

its not something pulling power its just that the alternator is not producing it. because if i leave my car for a while, the battery still has charge to do stuff, until it completely dies of course.
Old 06-03-09, 12:53 PM
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Someone else had this issue. I cant remember exactly what the problem was but he had the same symptoms you are having. Battery is new, Alternator passes test, however, batter was not keeping a charge. It was some kind of sensor or relay of some sort. Search it up.
Old 06-03-09, 01:08 PM
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choithew
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k thanks, i'll look around for sensor or relay related problems, havnt had much luck searching though .

i just put the alternator back in and did some tests. kept the car on the whole time.
kept the car on for a little bit checked the battery volts 11.71
drove around a bit came back checked the volts 11.68
drove around a little more came back 11.64
the volts on the batter just drop as in the car is running solely on the battery.
Old 06-03-09, 01:11 PM
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My totaled 400 is having this problem right now. First the speakers turn off, then the woofer/stereo, then headlights, after that when i signal to turn or break the gauge dims and the needles all go to 0, after that the power steering gets hard and finally the car just dies. I think my problem is being caused a short circuit somewhere, after the accident my led spoiler no longer works, so i assume its there.

Not sure if my story helps you but i would look for a short somewhere.
Old 06-03-09, 01:24 PM
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Originally Posted by Ryeno
My totaled 400 is having this problem right now. First the speakers turn off, then the woofer/stereo, then headlights, after that when i signal to turn or break the gauge dims and the needles all go to 0, after that the power steering gets hard and finally the car just dies. I think my problem is being caused a short circuit somewhere, after the accident my led spoiler no longer works, so i assume its there.

Not sure if my story helps you but i would look for a short somewhere.
well my problem just started and was random, so i wouldn't know where to begin to look for a short if that's what it is. i wasn't in an accident, didn't work on my car for prob a good month so i couldn't of messed something up. and i cant last more than 1-1.5 hrs before a new battery becomes depleted of power.

i need to get this fixed, thinking about taking it to a mechanic as much as i hate that, but I've already missed 3 days this week of school, and that's a lot for 6 week classes!
Old 06-03-09, 06:50 PM
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the only other thing i can think of is i found someone else w/ a similar problem, he said he ran a jumper cable from the alternator to the battery to test if all the power is making it to the battery. guess i'll try that tomorrow, gotta get the cables from a friend. i hate when something like this happens, its a pain to diagnose. If i ever get this thing working i still plan on making a nice drift video...

any other ideas are welcome and appreciated!! thanks for everyones help so far!!
Old 06-03-09, 09:04 PM
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Originally Posted by choithew
the only other thing i can think of is i found someone else w/ a similar problem, he said he ran a jumper cable from the alternator to the battery to test if all the power is making it to the battery. guess i'll try that tomorrow, gotta get the cables from a friend. i hate when something like this happens, its a pain to diagnose. If i ever get this thing working i still plan on making a nice drift video...

any other ideas are welcome and appreciated!! thanks for everyones help so far!!
i was just about to suggest that as it happend to me, replace terminals and torque them tight as can be and take a wire brush to the battery posts. if still no luck try adding new grounds from battery to chassis and chassis to block.
is your battery light flashing or constantly on?
Old 06-04-09, 08:32 AM
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k, i'll probably do that, even though i think the connection is good at the terminals...

no, the battery light has yet to turn on
Old 04-06-14, 02:51 PM
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I'm having the same problem with my IS300. Can you tell me what you ended up doing to fix it?
Originally Posted by choithew
k, i'll probably do that, even though i think the connection is good at the terminals...

no, the battery light has yet to turn on

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