Alternator failure or something else?

Lincoln LS

  1. scjmc

    scjmc Dedicated LVC Member

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    On two seperate instances now I have started the car (02LS8 111K) in the morning to "check charging system" with alternator (battery icon) light on. My left HID was flickering due to low voltage I assume. Ive got a 50 minute drive to work, so I turn off everything and start driving. After a few minutes everything goes back to normal. The battery is about a year old, and the connections are clean. The alternator itself I cant even see except for the pulley. Is there any external source like a voltage regulator or something that can turn the alt on or off, or am I looking at a faulty alt for sure? Thanks...... BTW I put my back seat down so that I can see the RF lightning cap that has a voltage LED and it reads 14.1-2 volts all the time, but I didnt read it when the car was acting up.
     
  2. 97stscaddy

    97stscaddy Dedicated LVC Member

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    Alternator sounds like it's charging as it should. Have the battery tested. Do you have a multimeter?
     
  3. Lincoln Jealous

    Lincoln Jealous Dedicated LVC Member

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    i know the starter is one thing that usually get replaced, but i didnt have those cels
     
  4. joegr

    joegr Dedicated LVC Member

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    It sounds exactly like a failing alternator to me. The only other possibilities are the PCM and the wiring. (The PCM tells the alternator what voltage to charge to.) The odds are with the alternator. The brushes wear out sooner or later.
     
  5. Hernandez

    Hernandez Well-Known LVC Member

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    to check the alternator start the car and with the car running disconnect the battery, if the car shuts down you have a problem with the alternator, if the car is still running your alternator is fine.
    how long have you had the problem? maybe the alternator got wet
     
  6. Andrizzle

    Andrizzle Dedicated LVC Member

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    Are you being serious dude?..
     
  7. bearsfan39

    bearsfan39 Dedicated LVC Member

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    1st: thats the stupidest thing i've ever heard, "oh lets disconnect the battery while its running, and if its still running after i disconnected it its fine"

    2nd: is it me or is your solution always "the alternator got wet"?
     
  8. Hernandez

    Hernandez Well-Known LVC Member

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    the battery is just for starting the car if the alternator is bad when you disconect the battery while running the car will turn off. thats like the most common test for alternator. if your alternator is fine your car should continue as nothing happened until you turn it off.

    and my alternator got wet and i had similar troubles when that happened thats why i say that.i believe this forum is to share experiences and possible answers, and i just wrote ONE post about my alternator.
     
  9. bearsfan39

    bearsfan39 Dedicated LVC Member

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    i may not be the most knowledgeable person on here, but i've never heard of disconnecting the battery while the car is running to test the alternator and i'm sure there are much better ways to check it

    i don't really want to know how you got your alternator wet and ruined it, but the fact is that parts wear and need to be replaced eventually and odds are that the alternator has not gotten wet, actually i would have never even thought of that as an option
     
  10. Alax7

    Alax7 Dedicated LVC Member

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    It doesn't seem like a stupid thing to do, to me. I think my dad told me this too, that this was a simple test, he use to be a mechanic and work on cars that were more mechanical that electrical, none of this use a voltmeter, multimeter stuff. I also was under the impression the battery was just for starting and using some electrical stuff while the car was off so this test would seem like it would do the job. Yeah, i'm sure there are better, more accurate ways to check it, but it doesn't mean it wont work. It's like saying the only way to know if your bone is broke is by getting an x-ray.
     
  11. bearsfan39

    bearsfan39 Dedicated LVC Member

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    it just seems dangerous to me and i would not do it, i could be wrong but it just seems like it wouldn't work
     
  12. Alax7

    Alax7 Dedicated LVC Member

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    Well, if the alt is bad and can't keep the car running, it will just turn off wont it. Maybe the ls, with all it's electrical and weird interferences, will have some freak new problem if you leave the alt running with no battery, who knows.
     
  13. rt2barbers

    rt2barbers Active LVC Member

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  14. lsdarkshadow

    lsdarkshadow Dedicated LVC Member

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    that seems to cover that...
     
  15. joegr

    joegr Dedicated LVC Member

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    It worked okay in the old days when cars weren't full of electronics.
    Now, it's a good chance that you will blow up some expensive electronics doing this trick. (Just because you get away with it once, doesn't mean you will next time.)

    My father blew out a couple of electronic modules in his 85 Crown Vic trying this trick. The alternator was good, but he spent way more than the cost of an alternator getting the car fixed after that.
     
  16. 1LoudLS

    1LoudLS Dedicated LVC Member

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    dude you are full of fukcing fail, the battery doesn't just start the car, it also acts like a filter in the system. you might just want to stick to old chevy's and carburetors before you fukc up somebody else's car

    this only works on el camino's and donkeys, which your village must have a lot of.
     
  17. Andrizzle

    Andrizzle Dedicated LVC Member

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    At first I thought he was trolling, but now I see the light. Like the others have said, the battery is a critical unit to buffer the voltage and current being received by the electronics in the car, especially the LS - being so computerized.
     
  18. 1LoudLS

    1LoudLS Dedicated LVC Member

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    i mean look at how ape sh!t the cars goes when the battery starts to fail and the alt is fine!
     
  19. Lincoln Jealous

    Lincoln Jealous Dedicated LVC Member

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    +1, then it messes with the starter
     
  20. joegr

    joegr Dedicated LVC Member

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  21. dNyce LS

    dNyce LS Dedicated LVC Member

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    It is dangerous, if u don't kno what you're doing or ar not being careful enough. When I was at NTB, that was the way they told me they did batteries, instead of using a battery saver. I've been doing batteries that way since then (mainly cuz I don't want my radio settings lost and having to relearn ish with the LS). But I do customers cars like that
     
  22. Hernandez

    Hernandez Well-Known LVC Member

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    ITS ONLY DANGEROUS IF YOU ARE STUPID

    you are not going to grab both ends at the same time or put them in your mouth. it wont blow or f*uck anything. you dont need to know what you are doing, JUST UNPLUG THE CABLES and thats it if the car still running the alternator is fine.

    the battery is not a filter or regulator thats why the power box, fuses, relays, etc are for. the battery just starts the car and gives power when the alternator is not working.
    google it.

    i dont live in a village.
     
  23. 05 LS8

    05 LS8 Dedicated LVC Member

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    The trick does work. I don't know how the LS would react to something like that though. I would be careful with it.

    I have tried out the test on my Mark viii, 03 Crown Vic, and got the right results on both cars.
     
  24. 97stscaddy

    97stscaddy Dedicated LVC Member

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    Electronics DO NOT LIKE the voltage variations that are created by the alternator. Modern control systems need constant steady voltage in order to work properly. The battery is used to keep input voltage constant so that the regulation circuits on the control units don't overheat and burn out. This concept applies to ALL electronics, not just what's in our cars. Ever heard of a brown out? They eat computer power supplys and TVs on a regular basis.

    The alternator creates alternating current waveform (hence the name). That means that the voltage waveform produced by the alternator changes polarity (+ - + - + -). If it were left alone like that the alternator would only be good for light bulbs. But electronics can't run on alternating current. It has to be converted to a DC current waveform by a set of diodes (known as a rectifier) in order to be used by the car. Problem is you still have fluctuations in the waveform as the alternator spins due to the way the electricity is being produced. The waveform bounces from ~14V to 0V dozens of times a second. The faster it spins the less time between fluctuations but they're still there. These changes in voltage are what causes the trouble. From that point this goes way deeper than I can explain without writing a book about the relation of voltage to amps and how all that is affected by the type of waveform being produced. But, this is where the battery comes in. The battery provides voltage between those fluctuations in order to keep a constant voltage going to the control modules of the car. Think of it like a capacitor for a big sound system. It in essence, soaks up, or "filters" out those small changes in the current.

    You can remove the positive cable from the battery while the engine is running, but it's not a good idea, nor is it a valid test. So the engine might stay running, but you don't know how many amps the alt is producing by doing that. Amps are just as important as voltage. Most parts stores will do charging system tests for free. You're much better off taking the car to one of them, than playing around with the battery while the engine is running and risk killing one or all of the control units in the car.

    I still say battery, although there is a possibility the alternator has a bad diode, or there is some other type of draw (sound system equipment not turning off as it should?) that is draining the battery as the car sits. But, I tend to think more along the lines that the battery is just going bad and is losing it's charge on its own.
    Removing the negative cable from the battery at night and reconnecting it the next morning should rule out a draw if the battery light still comes on once the engine is started.
    Or you can just have it tested.
     
  25. dNyce LS

    dNyce LS Dedicated LVC Member

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    ive taken mine out while running multiple times with my ls (couple times cuz my sentra battery died, another to start my in laws car, etc etc) from what ive experienced nothing negative happens to the car at all. the longest it has ran w/o a battery was about 8 to 10 minutes
     

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