The alternator contains an overrunning clutch (sprag type?) that allows it to spin freely as the engine winds down and only applies torque in one direction. I've seen a couple cases where they fail and make more of a ticking noise, but I suppose they could whine if they seize.
Alternator Whine - Hi, A couple of years ago I had my alternator die on me during a road trip. My care was only 3 years old at the time... Since then
So I have this alternator whine coming from my system in my car. It's a whining sound coming from the speakers while the head unit is on and the frequency of the whine is in sync with the engine RPM.
( The bearing in the alternator makes a whining noise when it’s about to failure.) Also check the volts off the alternator to confirm if it’s working correctly. Any parts store can check this for you for free. PS. Our 2011 Pilot’s alternator failed over the Labor Day weekend at 118k
Checked alternator its grounded and putting out correct amperage. This whining is beyond annoying and I can't seem to locate the source. I have some in-line noise suppressor but haven't installed them yet figured I'd check here first...
I heard whine noise and turned out the alternator bearing with low voltage generating, I replaced with new alternator $200 part + serpentine belt $15 part by myself. I don't believe the leaked coolant could reach to the alternator pulley which is located higher than the water pump. That stealership saying $1,200 is total B.S.
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