Battery getting overcharged!

[sumenlo]

So this started yesterday, to my knowledge. Basically, I tested the system while the car was running, and the battery was being charged at 20 volts! Obviously that's way above the 14 that it's supposed to be at. My question is this: Since the problem is most likely with the voltage regulator, is my solution replacing the alternator? I know that on a lot of older cars, they had a voltage regulator that was separate from the system, but helped regulate the power going to the battery from the alternator. What's the case with our cars? Is the regulator part of the alternator or is it still separate? My car runs okay for a little while, but it's boiling all the water out of the battery and into the engine compartment. Eventually, the battery will stop holding a charge and my car will die.

On a side question, will this ruin my battery, or can I just re-fill the water and charge her up? I just bought a new battery last night to replace the original and I'd hate to ruin another battery right off the bat.

 

[robs90tsi]

Replace your alternator, I believe that is where the voltage regulator is located, sounds like your alternator is bad, overcharging your battery, replace the alternator before putting that new battery in, and that should solve your problem.

EDIT: Yes, only on the N/T is the voltage regulator located on the PCM (ECU). In your case (and mine), the alternator.

 

[sumenlo]

I actually have a lifetime warranty on my alternator, so that will be an easy fix. The only other question I have, is whether my battery will be okay after this? Is it ruined or can I still use it? I guess I can always use my wal-mart warranty on it and get it replaced for free =)

 

[importboost]

When you boil the water out of the battery it will ruin it. It will take acid with it and you cant replace the acid and get the specific gravity back to where it needs to be so that the battery life is as long as you want. When you replace the alternator go ahead and get a new battery too.

 

[sumenlo]

So got the alternator out and took it up to the local checker. The test showed that it was bad. Got a new one and now I'm good to go. Turns out that I had leaked some power steering fluid onto the alternator housing and it effed up the voltage regulator. As far as the battery is concerned, we tested the voltage before starting it up and it was reading right at 12. Doesn't look like I hurt the battery for the one night that I drove it on the bad alternator. This wound up being the 3rd alternator since last september for my car. Pretty ridiculous if you ask me.

 

[importboost]

So got the alternator out and took it up to the local checker. The test showed that it was bad. Got a new one and now I'm good to go. Turns out that I had leaked some power steering fluid onto the alternator housing and it effed up the voltage regulator. As far as the battery is concerned, we tested the voltage before starting it up and it was reading right at 12. Doesn't look like I hurt the battery for the one night that I drove it on the bad alternator. This wound up being the 3rd alternator since last september for my car. Pretty ridiculous if you ask me.

You really need to get your battery tested before you think everything is ok. Just because it had 12v doesnt mean the battery is good. There are lots of things that batteries do that you wont find they are bad till they either die on you or you can find out by testing them.

 

[lasertim]

You really need to get your battery tested before you think everything is ok. Just because it had 12v doesnt mean the battery is good. There are lots of things that batteries do that you wont find they are bad till they either die on you or you can find out by testing them.

This man speaks the truth. Go back to checker and buy a battery hydrometer and check every cell in the battery. If all of the cells read 100% than you are good to go, if one or more cells is different than the others than you battery is toast and you need a new one. The $2.99 hydrometer would be better than a dead battery some day after work or something.

One more thing, fix your powersteering leak and you will probably stop killing alternators Also, is the side heat shield still on your car? Alternators dont like excessive heat either.

 

[BUCK]

One more thing, fix your powersteering leak and you will probably stop killing alternators Also, is the side heat shield still on your car? Alternators dont like excessive heat either.

& soon your ECU will die from the repeated high Voltage / Alternator deaths.

 

[Morphius]

EDIT: Yes, only on the N/T is the voltage regulator located on the PCM (ECU). In your case (and mine), the alternator.

How is this the case? The volatage regulator is located in the altenator.


If the voltage regulator was not internal, it'd be called a generator with an external volatage regulator.

 

[sumenlo]

How is this the case? The volatage regulator is located in the altenator.


If the voltage regulator was not internal, it'd be called a generator with an external volatage regulator.

it really just depends on the car. A lot of older cars used to have the voltage regulators inline with the system, separate from the alternator. It was a little black box. Like robs90tsi stated, the turbo cars have them with the alternator, while the N/T cars are not.

 

[Morphius]

it really just depends on the car. A lot of older cars used to have the voltage regulators inline with the system, separate from the alternator. It was a little black box.

Yea, exactly what I said. And in that case, it wasn't an altenator, it was a generator.

Like robs90tsi stated, the turbo cars have them with the alternator, while the N/T cars are not.

Like I said, robs90tsi is wrong. NT, turbo, 1.6L, 1.8L, 2.0, 2.4L... name it, they are internally regulated IN the altenator.