High pitch whistle coming from engine bay

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Richard199

New Member
Joined
Feb 22, 2018
Messages
7
Location
Staffs
Car
GLC 350D premium plus
I have noticed a high pitch whistling noise that comes from within the engine bay on my 2017 GLC 350D. This happens after the car has been switched off and locked for over 45 minutes or so. I have uploaded a video to YouTube showing this.

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Anyone have any thoughts on this.
 
That is truly strange. I've got no idea what it could be, but I'd guess at something electronic like a malfunctioning alarm siren.
 
It does stop if you unlock the car or start it. However, once you stop the car and lock it, it then starts again. It only stops after the car cools down. It makes me thinks it is a pump or something that is whining as it pumps fluids but not sure.
 
I'm thinking along the same lines as PobodY - something electronic.

Perhaps the alarm.

If you do not lock the vehicle does it still make the noise?
 
I have noticed a high pitch whistling noise that comes from within the engine bay on my 2017 GLC 350D. This happens after the car has been switched off and locked for over 45 minutes or so. I have uploaded a video to YouTube showing this.

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For more detailed information, see our cookies page.

Anyone have any thoughts on this.
This is a very strange noise.

It does sound pump related to me but I could be wrong

I see your car is under 3 years old so still under warranty - I would head straight round the dealer and watch them scratch their heads.
 
Really weird and weirder as I had the same last night
Washed the car last night and there was an intermittent and slow whining at about the same pitch.
The car was not unlocked, so I was wondering if the jet wash had triggered a pre alarm (no electrics were active)

It went off after several minutes (felt like a long while) and seemed to be coming from the n/s/f wheel arch.....?

No fault codes showing on the TORQUE app and no battery issues (it started fine this morning)

But was worrying / is worrying....

Please let us know what you find out
 
Really weird and weirder as I had the same last night
Washed the car last night and there was an intermittent and slow whining at about the same pitch.
The car was not unlocked, so I was wondering if the jet wash had triggered a pre alarm (no electrics were active)

It went off after several minutes (felt like a long while) and seemed to be coming from the n/s/f wheel arch.....?

No fault codes showing on the TORQUE app and no battery issues (it started fine this morning)

But was worrying / is worrying....

Please let us know what you find out
Is your car under warranty?

I would go and book a slot at the dealer as this is a pretty strange noise

Drew
 
No harm in testing the alarm.


Open the drivers window

Lock the car with the remote

Wait 1 minute for the alarm to set

Reaching in through the open window and open the door

Alarm siren should sound for 30 seconds and the hazards will flash for 3 minutes, alarm should then reset itself


Dec
 
Apologies for piggybacking on this thread, but for the life of me, I can't figure out how to start my own thread. What is the secret??? Please tell.
There is a strange whirring / whistling noise coming from somewhere in the the dash in my w212. It happens a few seconds after turning on the ignition, and only last's a few seconds. Does not matter if the engine is running or not. Any idea's anyone?
 
Apologies for piggybacking on this thread, but for the life of me, I can't figure out how to start my own thread. What is the secret??? Please tell.

Top right of the screen when you are looking at a forum, just below the "Search" box, you should see "Post New Thread"?
 
Top right of the screen when you are looking at a forum, just below the "Search" box, you should see "Post New Thread"?
Hi fifermerc, Thanks for your help. I have uploaded a screen shot of what is on this page...but still cannot see "Post New Thread".....MB Club Pic Reduced.jpg
 
Use the home button, then go to correct section below , in this case Engine and you will see new thread box at top on right hand.
 
Good afternoon Richard,
Sorry to hear about your problem and maybe I can assist?

1) Is the noise louder inside the engine bay - Around the fuse box?
2) If so, remove the fuse box cover - Is the noise louder?
*) My theory is that a small auxillary fan (used in cooling the AirCon condenser - I believe) located in that area is simply dirty, or more accurately the fan impeller blades are dirty?
**) It may be possible to vacuum clean the fan whilst in situ, or remove 5/7 torx screws and remove the fan/clean/refit?

I do hope you find a solution, good luck :dk:
 
Sorry for resurrecting an old thread but does anyone know what this whislting noise ended up being as mine has started doing exectly the same thing. Have it booked into the dealers in a couple of weeks but would be good to give them a heads up is possible. Thanks.
 

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