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Discussion Starter #1
the other day I was cruising around town when my radio turn off (completely off with no lights),... i thought it was a fuse.

then the front lights start to get dimmed down bit by bit and the RPMs got really low and boom, the car shots down by it self,.. i tried turning the car back on, but the battery had no power.

Ok, good thing I had another alternator in my garage.
I took that alternator to auto zone and they check it and it was charging just fine.

and after 3 hours of hell trying to take the old alternator OUT of the engine BAY :mad: ................ I put the new used alternator that i had.

I put everything back together and i jump start the car and let it run for a minute,.. after a minute i take off the jumper cables and the car just dies again. OMG this is :bsflag:

If the alternator is "good", can there be anything else not letting it charge????

any help is appreciated,
Thanks.
Jon.
 

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Check the fuse box in the front of the car. Theres a 10 or 15 amp alternator sensing fuse, and a larger 120 amp main circuit fuse.
 

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Check your battery terminal connections. Mine had a tiny amount of corrosion and from time to time my lights would go dim and radio shut off. Then one day it wouldn't start altogether and I got out and moved the terminals around and it was good again. If that's not it you might have a bad ground wire. Good Luck
 

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I'd also look at the wiring harness (in the alternator area), it's possible a wire became severed completely, or just broke inside the sleeve. Either way it'd be a real pain to replace/fix.
 

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check the wiring to the rear fuse box, make sure the connection is good and that the wire running to the rear fuse has a good connection w. the alternator
 

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You may want to have your battery checked out. You most likely have a loose connection or a dead cell in your battery. The litmus test for your alternator is to start your car and while it is running, unhook the positive terminal from your battery. Your car should run just fine off the alternator. If it dies, you're alternator is bad. If it runs fine, your battery needs replacing.
 

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Check your GROUNDS.... Check the one going from the transmission housing to the chassis. Check the one going from the battery's negative terminal to the chassis... I'm willing to bet it's the transmission one... watch out, if you keep trying to run the car with bad grounds, you'll have a small fire in your engine bay....

Baktash
 

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Discussion Starter #8
i just checked my old alternator that was in there,.. it checked out good.
And I also took my battery for check/recharge and is holding the volts just fine.

I took a quick glance at the fuses in the front, they looked ok, but it is dark and I will recheck them whenever there is light.

The car starts and runs fine, but it just eats from the battery instead of the alternator. :dontknow: ..... the alternator is fine and so is the battery.

baktasht,.. the tranny ground wire you're talking about, can I see it from top?

I dont have to much time to check it on weekdays,.. but hopefully it will be fixed by the end of the weekend......... if I find the problem.
 

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Discussion Starter #9
oh yeah,. another thing,...... the battery light in the gauge cluster is not on, and it never turned on while the car was sucking the battery's juice.

any thoughts?
 

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Go to your local autoparts store, buy some braided steel grounding straps (at least 3) connect one from anywhere on your transmission housing to somewhere sturdy on the chassis, connect the second one from your negative battery terminal to your chassis (replacing the old black one), and the third from your transmission mounting bracket to the chassis. Make sure you clean all of the contact points, and scrape the paint off if there is any so that you can make a good contact. On our old cars, even if you're not having grounding problems right now, it's still worth the few dollars and 20minutes to make sure it doesn't become a problem later on.

The other thing, When you put in the new AFM (and took out the old one) did you unscrew the two small screws on either side of the connector? If you did, then you probably killed the AFM and that is your problem. Another thing to check, check all of your intake hoses. One that usually starts cracking on our old cars is the piece that goes from the AFM to the turbo inlet. The side that connects to the turbo starts cracking. Even if it is tight on there, go ahead and take it off and check it. Also, check all of your vacuum hoses.

Baktash
 

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on our alternators the voltage regulator is built in. I think it might be replaceable, but it is still part of the alternator. Shouldn't it show up as being bad during the bench test?
 

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i have no idea, lol thats the only thing i can think of using excessive power or not enough..
 

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Spooling Dreams said:
oh yeah,. another thing,...... the battery light in the gauge cluster is not on, and it never turned on while the car was sucking the battery's juice.

any thoughts?
I believe someone said to check the harness on the alternator already but check it again! that was the problem I had after I swapped alternators. I thought I had it in pretty tight but to my suprise it wasn't even snapped in all the way. I had to use a hammer to snap it in? No battery light or oil light.. weird..
 

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Discussion Starter #16
well,.. i do have an oil light do to my gen2 JDM swap.. but thats a different story.

i double checked the alternator plug, and it did snapped in good.
I used one of those pen lights or whatever they are called, i put the clip on ground and the other to the 10mm bolt that goes to the alternator, and the light seemed to light up pretty bright. this was with the car off,... key in w/ twist #1,... and key in w/ twist #2 (all gauge lights lighted up).

baktash,... would a bad ground or no ground at all to/from the tranny cause the alternator not to charge? or would it even let the car turn on??

i just put in my recharged battery in, and the car starts and runs,.. but it sucked all the battery's juice again within 30 minutes or so. damn, this car is nothing but headaches.
 

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Discussion Starter #17
problem fixed :)

turned out to be a darn fuse in the rear fuse box,... the box is a little scratched, so i can not read what the fuse is for,.. but it is the only 7.5 fuse in there.

thanks to all.
 
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