Battery light comes on intermittently

[Rearro]

Where Is the Alternator? Can somebody take a picture of it? And how do you check if it is working properly? Sorry for the Stupid questions?? My light is coming on and it goes off for a while and them comes back!! Grr

Pls. Help!!

[JCL]

Originally Posted by Rearro

Where Is the Alternator? Can somebody take a picture of it? And how do you check if it is working properly? Sorry for the Stupid questions?? My light is coming on and it goes off for a while and them comes back!! Grr

Pls. Help!!

It is under the hood. To test it you take it to a shop that has the proper equipment to test both the battery and the charging system. If you don't want to take it to the dealer, take it to an independent shop.

[Rearro]

Thanks JCL
I went out to the STEALER and purchased a $230 battery and It didn't fix my problem so I know the Battery is good, But I put it on a trickle charger just to make sure the battery wasn't drained from the dealer.
But after reading this thread I am thinking I may have an Alternator issue!!

I would like to do this my self any idea on the level of difficulty?

[Ldiggs910]

Sooo. I realize I didnt report back on this thread and thats because the problem really wasnt fixed until just this past month.

This is ultimately what occured but I'll kinda start from the beginning.

1. One day my alternator simply stopped charging the battery.
2. When I realized it I was on my way to work which is 20 miles away from my mechanic.
3. I basically drained an already old battery (which also was leaking apparently) all the way dead on the way to the mechanic
4. He replaced the alternator with some random aftermaket brand because that was what my aftermarket warranty company was willing to pay for.
5. The battery light continued to flash intermittently after the alternator was replaced.
6. I replaced the battery thinking because it was leaking it was defective (that wasnt necessarily true because it was still charging up fine, its just the light kept flashing).
7. This past March I had a DIFFERENT mechanic look at it and he says its the alternator.
8. I told him it the battery charges fine and he acknowledged that the charging/electrical sytems/voltage WAS correct but that it was the alternator.
9. So the warranty company AGAIN pays for the replacement of the alternator only THIS time he uses a Bosch brand alternator.
10. After over a year of battery light flashing, my problem is gone.

I updated this thread because I've been helped so many times by "old" information and I figured somebody might be having this very issue

[4.6toddy]

I replaced my alternator 3 months ago. 4.6is liquid cooled
no troubles, no lights since then. battery light came on again yesterday, intermittently then solid, then off 100km later and now on again around town.

faulty alternator or voltage regulator? is there a way to test the voltage regulator?

[ssx5]

Ok...I am trying to reactivate this dead thread.

On my 05 E53 I have replaced my Battery as part of regular maintenance about 2 months ago. It was over 3 yrs old.

I have since replaced Crankcase housing and Oil filter housing gaskets. Everything worked out perfect. A month and half after the above jobs the Battery warning light comes on intermittently. The night before I drove while there a heavy poring rain. I checked the under the engine for the plastic oil catch and metal plate. Looked OK except on the metal one there were two opening. Not sure if it is like that or or Inde idiot that worked on my X5 forgot to put it back or worse STOLE it. Sorry for being mean.

So my question is due to the rain and condition below the engine contributed possibly for the alternator or the voltage regulator going bad?

Your thoughts appreciated.

[Fifty150hs]

Originally Posted by ssx5

Ok...I am trying to reactivate this dead thread.

On my 05 E53 I have replaced my Battery as part of regular maintenance about 2 months ago. It was over 3 yrs old.

I have since replaced Crankcase housing and Oil filter housing gaskets. Everything worked out perfect. A month and half after the above jobs the Battery warning light comes on intermittently. The night before I drove while there a heavy poring rain. I checked the under the engine for the plastic oil catch and metal plate. Looked OK except on the metal one there were two opening. Not sure if it is like that or or Inde idiot that worked on my X5 forgot to put it back or worse STOLE it. Sorry for being mean.

So my question is due to the rain and condition below the engine contributed possibly for the alternator or the voltage regulator going bad?

Your thoughts appreciated.

I'm guessing you're about to lose your alternator. I got the intermittent battery light a few times before the alternator totally took a dump and stranded me.

[oldskewel]

Missing access hole covers in the stiffening plate - I don't think that's a big deal. My car was like that when I got it 2 years ago (and still is) and I'm not concerned. Very doubtful that it would be related to your alternator problem.

When the alternator on my '01 3.0i went out (VALEO 120 Amp alt), the charging light would come and go intermittently for a very short window until it died completely. Turned out this was the more-worn of the two brushes finally wearing down enough to lose contact with the slip ring.

On my alternator, the brushes assembly is part of the Voltage Regulator. At the time, I could not wait to get all the parts (bearings, slip rings, etc.) for a more complete rebuild, so I just replaced the Voltage Regulator. That's where I would start looking if I were you. If that is the problem, clearly neither rain nor open access ports had anything to do with the failure. It's just normal wear. Mine went at around 170k miles, which I think is typical for those cars/alternators.

[ssx5]

Originally Posted by Fifty150hs

I'm guessing you're about to lose your alternator. I got the intermittent battery light a few times before the alternator totally took a dump and stranded me.

Thanks Fifty150hs.. I will replace or rebuild the alternator. May be replace voltage regulator too while I am there. Appreciate your thoughts

Originally Posted by oldskewel

Missing access hole covers in the stiffening plate - I don't think that's a big deal. My car was like that when I got it 2 years ago (and still is) and I'm not concerned. Very doubtful that it would be related to your alternator problem.

When the alternator on my '01 3.0i went out (VALEO 120 Amp alt), the charging light would come and go intermittently for a very short window until it died completely. Turned out this was the more-worn of the two brushes finally wearing down enough to lose contact with the slip ring.

On my alternator, the brushes assembly is part of the Voltage Regulator. At the time, I could not wait to get all the parts (bearings, slip rings, etc.) for a more complete rebuild, so I just replaced the Voltage Regulator. That's where I would start looking if I were you. If that is the problem, clearly neither rain nor open access ports had anything to do with the failure. It's just normal wear. Mine went at around 170k miles, which I think is typical for those cars/alternators.

Thanks oldskewel for your insight. The reason I got that doubt about the open access ports was because I saw splashed rain water all over under the hood and I see the battery warning light flash the very next morning of a heavy rain.

I am ordering voltage regulator and thinking of having the alternator rebuilt. But if I decide to go with a new one I may go with a Bosch. But not sure about the difference between 120 Amp and 140 Amp for my '05 X5. Will do some reading on this.

Thanks again...