How can you test if your alternator is not working?
02-07-10, 12:39 PM
#3
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1. start your car first
2. then unhook your battery.
the alternator should power your car while its running if its not bad. give it a few minutes to test. if the engine shuts off then your alternator is bad. also check if there is oil dripping from above it because oil could leak down on the alternator from the distributor making it go bad.
hope this helps
2. then unhook your battery.
the alternator should power your car while its running if its not bad. give it a few minutes to test. if the engine shuts off then your alternator is bad. also check if there is oil dripping from above it because oil could leak down on the alternator from the distributor making it go bad.
hope this helps
02-07-10, 02:57 PM
#4
1. start your car first
2. then unhook your battery.
the alternator should power your car while its running if its not bad. give it a few minutes to test. if the engine shuts off then your alternator is bad. also check if there is oil dripping from above it because oil could leak down on the alternator from the distributor making it go bad.
hope this helps
2. then unhook your battery.
the alternator should power your car while its running if its not bad. give it a few minutes to test. if the engine shuts off then your alternator is bad. also check if there is oil dripping from above it because oil could leak down on the alternator from the distributor making it go bad.
hope this helps
02-07-10, 07:20 PM
#5
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The car actually shuts off on me while running. I can't start it up now because the battery is totally drained.
I had the volt light on before it turned off on me. I jump started it twice and it would not keep a charge after starting. I guess that totally means that it's the alternator, right?
I had the volt light on before it turned off on me. I jump started it twice and it would not keep a charge after starting. I guess that totally means that it's the alternator, right?
02-07-10, 10:07 PM
#7
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Do not ever disconnect the battery whilst the car is running.
The alternator uses the battery sense wire to determine the level of charge and therefore the alternator output. If you open circuit the system the alternator can overcharge and blow diodes in the rectifer.
The correct way to test an alternator is to place a load on it, fans, lights etc and measure the output voltage using a multimeter. It should be about 14.2 volts all the time.
Matt.
The alternator uses the battery sense wire to determine the level of charge and therefore the alternator output. If you open circuit the system the alternator can overcharge and blow diodes in the rectifer.
The correct way to test an alternator is to place a load on it, fans, lights etc and measure the output voltage using a multimeter. It should be about 14.2 volts all the time.
Matt.
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02-08-10, 05:38 PM
#8
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I'm guessing this is what's wrong with mine. Drove great up until I would use the brake and then the power would drain and kill the car, or if I was using the stereo it would die. Good to know it might not be a wiring ghost.
02-08-10, 06:14 PM
#9
I think Advanced auto or autozone can run both of these test on your car actually to test the battery and the alternator. They test the alternator with the battery in the car, and test the battery while its out of the car.
They don't really like to do these tests but if you are persistent they should, especially if you say you want to buy a battery/alternator.
They don't really like to do these tests but if you are persistent they should, especially if you say you want to buy a battery/alternator.
Last edited by Ali SC3; 02-08-10 at 06:27 PM.
02-08-10, 06:34 PM
#10
mine just died on me yesterday...
the battery light kept coming on while i was driving, my volt meter on my timer and headunit was only at 11.5v when i started driving and ended up at 10.7 when i got home. i shut off the car and tried to start it back up... and it didnt
the battery light kept coming on while i was driving, my volt meter on my timer and headunit was only at 11.5v when i started driving and ended up at 10.7 when i got home. i shut off the car and tried to start it back up... and it didnt
02-09-10, 04:16 PM
#13
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simple test.
Take battery voltage with a volt meter with the car turned off. SHould be near 12v. Turn on the car and while its running check the battery. SHould be around 13-14v. If its still under 12 volts your alternator is not charging your battery
Take battery voltage with a volt meter with the car turned off. SHould be near 12v. Turn on the car and while its running check the battery. SHould be around 13-14v. If its still under 12 volts your alternator is not charging your battery
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