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Whenever I rev the engine the lights get brighter. They say that is a sign of the alternator being bad, but could it be the battery because I just got a brand new alternator from Autozone yesterday. My belts are pretty tight too.
 

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Slight > in brightness is expected....should not be severe. Do you have other electronics running?
 

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its not the battery. turn the car on...take the battery out while the car is on. It will stay on if your alternator is good. then try to rev the engine. It has to be your alternator.
 

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Just throwing this out there. It could be your voltage regulator, unless the supra alt has it built in. Also it very well could be your battery. If you alt went bad and you ran it for a while its possible to screw up your battery, I would have it tested. Same thing happened on my other car a few months ago.
 

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XTC Dynamic Supra said:
its not the battery. turn the car on...take the battery out while the car is on. It will stay on if your alternator is good. then try to rev the engine. It has to be your alternator.
Unplugging your battery while it was running could cause major problems
 
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What else do you have installed electronic-wise? There is a ton of electric crap that runs on our car.
 

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AZmkiii said:
Unplugging your battery while it was running could cause major problems
naaa kant be...dats the only effective way in my opinion to see if your alternator is good. unplug the battery while the car is running, if the car stays running, and u can rev it...ur alternator is good.:cool: :cool:
 

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XTC Dynamic Supra said:
its not the battery. turn the car on...take the battery out while the car is on. It will stay on if your alternator is good. then try to rev the engine. It has to be your alternator.
NOT a good idea....this can lead to a severe voltage spike in your car's electrical sys (think about it- you're removing the primary load...).....
 

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kevman05 said:
naaa kant be...dats the only effective way in my opinion to see if your alternator is good. unplug the battery while the car is running, if the car stays running, and u can rev it...ur alternator is good.:cool: :cool:
once again, completely false. i test automotive electrical systems for a living, that very test is the most destructive test we do.....
 
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the alternator needs current to make its magnetic field. If you take the battery out and there is enough electrical load elsewhere, the car will die.

I vote battery, or battery connection. Do you own a volt meter?
 

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ALTERNATOR

THE REGULATOR IS DONE.
CHANGE THE ALTERNATOR NNNOOOWWW
BEFORE YOU GET INTO DEEP SH..
I'VE HAD THAT PROBLEM BEFORE.
 

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djmtpocket said:
Just throwing this out there. It could be your voltage regulator, unless the supra alt has it built in.
I think all modern alternators have bulit in regulators.
 

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OMG YOU
BETTER JUMP ON
REPLACING THAT
ALTERNATOR, OH SH..
 

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We have a discussion once a day on batteries, alternators, and starters. And once a day someone tells another person to disconnect the battery to check the alternator. While this was a good "test" with a pre 80's car, this can cause major problems with newer cars, as many other people have already stressed many times. If you want to check the alternator or voltage regulator, do like we did at Interstate Batteries. Invest in a cheap little voltmeter, connect it to the battery and watch for more than 13.8 volts....I'm sure someone knows exactly what a Toyota alternator puts out. If you have any large fluctuations then it could be the regulator. I'm betting that you need to take the battery out and give it a nice little charge overnight at 2amps works great. Allow the battery to stablize for 3-4 hrs if you want to get an accurate voltage reading. Otherwise stick it in, it should be fully charged.
Batteries are used to crank the starter, dampen the voltage coming from the alternator to prevent voltage spikes and we use it to power the car when the engine is off. Alternators power the whole electrical system with the engine running and recharge the battery, keep in mind it takes a long time to recharge not just a 20-30 min drive. I've said this before but 50-60% of the batteries we recieved as cores were indeed good batteries. Which in turn we sold as used batteries. One of the best tools to use when checking yoru battery is a 3 dollar hydrometer, and its simple to use.

Jeremy
 

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dang dont jump on my back on this....im not telling the guy to drive the car around with the battery out. its a matter of disconnecting the battery and one rev. yes you can have a spike but tell me you guys have never tested someones or even your own alternator this way. shit this is the way to do a ghetto jump start. Tell me if your stuck somewhere with a dead battery. Your buddy happens to be there with a running car and a battery that works. tell me you wouldn't take his battery to start your car then drop back your battery once it's started. Believe me...You'll do it.
 

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we are just saying, i would rather call AAA and have a jump, then ruin my ECU and deck, and e-manage, and profec....
 

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We're not ganging up on you, but listen to what you just said......Ghetto. And he;s not stuck on the side of the road with no other options. Lets try to get people to do it the right way first, it may cut down other problems. Not trying to start anything, I just want people learn the right way.

Jeremy
 
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