Nessmuk
Well-Known Member
My alternator makes a hum noise even when the key is off. This is the one that causes the alt light to glow when the key is off. What causes that?
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Humming alternator when off.
- Thread starter Nessmuk
- Start date
Will L.
Well-Known Member
Demonic possesion?
Just a guess here mind you, I never seen this one.
The humming would be an electrical arc inside disconnect your battery or the lead connections and see if it goes away- guessing it is putting a draw on the batts and shorting something out inside.
If you are comfortable pulling it apart, look for arcing signs.
The Oriellys here has the newer alternator component test where they can say which part is at fault- just a thought.
Just a guess here mind you, I never seen this one.
The humming would be an electrical arc inside disconnect your battery or the lead connections and see if it goes away- guessing it is putting a draw on the batts and shorting something out inside.
If you are comfortable pulling it apart, look for arcing signs.
The Oriellys here has the newer alternator component test where they can say which part is at fault- just a thought.
Pull the plug and see if the humming stops. If so it's getting power to "turn on" the regulator from somewhere else through the plug. Aka something says ignition on, engine should be running, generate power.
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