Squeel/buzzing sound
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From: MD
2007 C230 and 1985 Monte SS
Squeel/buzzing sound
I was working on my other car and the Benz was parked next to it, and again, I hear this squeel/buzz sound every 30 seconds or so. Its not a regular interval between every one. So I pop the hood and from the best that I can tell, its coming from whatever accessory is all the way on the bottom of the driver side (A/C Compressor? P/S pump? there are pressed lines going into it)
It really sounds like some sort of electric servo actuating. This is with the car off and the key can be in or out, any position on the ignition, as long as the engine isn't running (well, maybe it happens when the engine is running, but I can't hear it)
2007 C230SS M272
It really sounds like some sort of electric servo actuating. This is with the car off and the key can be in or out, any position on the ignition, as long as the engine isn't running (well, maybe it happens when the engine is running, but I can't hear it)
2007 C230SS M272
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
SSM - Bottom pulley is Aircon compressor. Are you sure the sound is electrical & not the refrigerant settling down. How long after shutting down the car can you still hear it?
Last edited by Glyn M Ruck; Apr 6, 2009 at 01:15 PM.
Thread Starter
Super Member
Joined: Dec 2008
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From: MD
2007 C230 and 1985 Monte SS
I guess it could be the refrigerant passing through a small passage. It lasts about a second per occurance before the longer ~30-60 second pause. I have only really noticed it shortly after driving, I'll have to take a listen after its been sitting for a while.
If it is indeed the A/C compressor making this noise, I assume its nothing to worry about?
If it is indeed the A/C compressor making this noise, I assume its nothing to worry about?
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Joined: Jun 2008
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Yeah! - I would not loose sleep. Refrigerant can remain mobile for quite a while after shut down - it's ambient temperature related so I don't want to guess how long. Listen to the car after it's been shut down 4 plus hours & see if it still makes a noise. You are not the first one to report this but it's never really been resolved on the forum.
Thread Starter
Super Member
Joined: Dec 2008
Posts: 526
Likes: 1
From: MD
2007 C230 and 1985 Monte SS
