Should the alternator make a buzzing sound with the key on engine off?
Should the alternator make a buzzing sound with the key on engine off?
Noticed a buzzing coming from the alternator with the key on in my quiet garage tonight. Any clues as to if or why it would do this?
Joined: Sep 2005
Posts: 27,904
Likes: 2,437
Car: Yes
Engine: Usually
Transmission: Sometimes
Axle/Gears: Behind me somewhere
Re: Should the alternator make a buzzing sound with the key on engine off?
No it should not do that.
Probably run your battery down if you leave it like that.
Probably run your battery down if you leave it like that.
Member
Joined: Sep 2007
Posts: 397
Likes: 42
From: The ******* of Texas
Car: '89 Firebird Formula
Engine: TBI 305
Transmission: T5
Axle/Gears: 10-bolt, 3.42s, Torsen diff.
Re: Should the alternator make a buzzing sound with the key on engine off?
It sounds like something - maybe your ignition switch - is delivering power to your alternator's voltage regulator when it shouldn't.
Key-on-engine-off, my car makes the same noise.
Like sofakingdom said, that will absolutely drain your battery.
Get out your voltmeter, and check the rectangular plug on your alternator to see which terminals have power, then report back to us with the results.
Key-on-engine-off, my car makes the same noise.
Like sofakingdom said, that will absolutely drain your battery.
Get out your voltmeter, and check the rectangular plug on your alternator to see which terminals have power, then report back to us with the results.
Joined: Sep 2005
Posts: 27,904
Likes: 2,437
Car: Yes
Engine: Usually
Transmission: Sometimes
Axle/Gears: Behind me somewhere
Re: Should the alternator make a buzzing sound with the key on engine off?
The regulator (inside the alt) has full battery power applied to it; not all of it comes through the ign sw.
Thread
Thread Starter
Forum
Replies
Last Post
92Z
Tech / General Engine
6
Nov 8, 2010 01:00 AM
DartByU
Tech / General Engine
5
Jun 8, 2008 05:45 AM