Buzzing/electrical noise from engine after shutdown
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Member
Joined: Oct 2010
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From: St. Louis
2020 GLC63
Buzzing/electrical noise from engine after shutdown
The last few days it's been really, really hot here in STL. I've noticed a couple of times when, after pulling the car into the garage and shutting it off, I hear what sounds like an electrical motor humming away in the engine bay. I've had a little trouble localizing it, but it's definitely there and it lasts for awhile, I'd say at least an hour. I also notice that at random times after shutoff, again for at least an hour, probably more, I hear a release of air from the rear suspension. Anything I should be concerned about? I've been able to get the hum started up again when, after the car has sat and the noise is off, I open and close a couple of doors, that seems to get the cycle going again.
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2014 E63S; AMS 100 octane ECU dyno tune; EDOK TCU tune; BB intakes; sprintbooster
There is a hvac fan that runs to kill the humidity and moisture and also the led headlamps have fans that run
there is a tsb to correct an issue if it's running for longer than say 10 minutes
there is a tsb to correct an issue if it's running for longer than say 10 minutes
Out Of Control!!
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2014 E63S; AMS 100 octane ECU dyno tune; EDOK TCU tune; BB intakes; sprintbooster
i get releases of air hours after the car has been off and I'm approaching the car with a key in pocket ... that's normal ... like she's getting ready for ya and releasing some gas!
Thread Starter
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Joined: Oct 2010
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From: St. Louis
2020 GLC63
Out Of Control!!
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2014 E63S; AMS 100 octane ECU dyno tune; EDOK TCU tune; BB intakes; sprintbooster
Also keep in mind if the key is in your briefcase and near the garage the car will always think you're in proximity and make some noises
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From: Miami, FL
2003 CL 600
Air release is normal due to heating of the bags, as the car sits and they warm up they expand, so when the car checks it's level, it's too high and pops off a bit from wherever it needs to.
The noise is as mentioned, a fan or aux pump, and it's normal for them to run up to an hour after shutdown to control temperatures, anything you do to wake the car back up will reset that time on most things. Some are keyed to engine shutdown but things like the cooling for the lights is not.
The noise is as mentioned, a fan or aux pump, and it's normal for them to run up to an hour after shutdown to control temperatures, anything you do to wake the car back up will reset that time on most things. Some are keyed to engine shutdown but things like the cooling for the lights is not.
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poop
Kind of surprised it hasn't been mentioned in this thread, most of the humming noise is from the LED headlights. They have a fan inside that runs quite a while after the car is shut down.
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Humming / electrical noise from middle vent only
Tonight I noticed after shutdown a humming/electrical noise from the middle vent . Usually the electrical noise stops after a minute or so but tonight it just kept going . It’s about 40 degrees in Ny not sure why it just started to do this !! Can this kill my battery
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2014 E63S; AMS 100 octane ECU dyno tune; EDOK TCU tune; BB intakes; sprintbooster
what's the noise sound like when you open the hood? Could still the above culprits and if so, no it won't kill your battery but wise to keep these cars on a tender if not driven weekly
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2014 E63S; AMS 100 octane ECU dyno tune; EDOK TCU tune; BB intakes; sprintbooster
