Alternator
Thread Starter
Burning Brakes
Joined: May 2003
Posts: 990
Likes: 0
From: Germantown TN
Alternator
Could an old alternator that still works be draining my battery while not in use? Something is drainging my battery down and that's one thing someone told me to look into but i wasnt sure if that was true or not. Any help? :confused:
Le Mans Master
Joined: Apr 2001
Posts: 5,000
Likes: 1
From: Minneapolis, Mn USA
Re: Alternator (ElectronBlueC3)
Ive seen it before. Alternator is working but draws down the battery when not running. Its one of those wouldnt believe it until youve seen it type deals.
I think the regulator can have a failure mode where it is still capable of regulating at 14V but has a current draw problem due to a bad transistor stage in its control circuitry. Regulators can have many transistor PN junctions which perform many different tasks regarding regulation.
Brent...
I think the regulator can have a failure mode where it is still capable of regulating at 14V but has a current draw problem due to a bad transistor stage in its control circuitry. Regulators can have many transistor PN junctions which perform many different tasks regarding regulation.
Brent...
Pro
Joined: May 2003
Posts: 601
Likes: 0
From: Nottingham
Re: Alternator (ElectronBlueC3)
Yep, I know that's perfectly possible..
Not sure of the exact details of how it happens, or if indeed it's what happening with you, but the battery can definitely be drained by a faulty alternator. One way to check, stick an ammeter in series with one of your battery terminals and the corresponding battery cable, and see what current is being drawn at with the key out. Then disconnect the live cables from the alt and see if this current drain goes away. If so, bingo!
Use a high range on the ammeter at first, to avoid blowing any of its internal fuses!
[Modified by theoUK, 12:01 AM 1/20/2004]
Not sure of the exact details of how it happens, or if indeed it's what happening with you, but the battery can definitely be drained by a faulty alternator. One way to check, stick an ammeter in series with one of your battery terminals and the corresponding battery cable, and see what current is being drawn at with the key out. Then disconnect the live cables from the alt and see if this current drain goes away. If so, bingo!
Use a high range on the ammeter at first, to avoid blowing any of its internal fuses!
[Modified by theoUK, 12:01 AM 1/20/2004]
Thread Starter
Burning Brakes
Joined: May 2003
Posts: 990
Likes: 0
From: Germantown TN
Re: Alternator (mvftw)
Well I just disconnected it completely. Hopefully I will see some results pretty soon. I don't have an ammeter or anything like that yet. Gotta do it the ole fashioned way. :smash:
