Strange AC noise

[djpill]

Can somebody possibly identify what noise is coming from my AC? Its like a humming sound and it only happens (intermittently) when I have my AC on and it's actually blowing cold air. In fact when it is happening, if I turn my AC button off the sound goes away immediately.

Dealer is struggling with this and my warranty is almost out (although this should be warrantied an additional 12 months due to a prior repair attempt made). The sound is coming from behind the left drivers vent, and they already replaced the vent itself (dumb since it's not a fan issue) and they just did a full recharge of the AC system (freon drain and change).

https://youtu.be/skG8wHZSOis

Thanks in advance. 2013 S6.

[A U D I]

Does the sound go away when deselect the A/C or just when you turn it off completely ?

[djpill]

Does the sound go away when deselect the A/C or just when you turn it off completely ?

goes away immediately after i turn off the AC by pushing the AC button (fans still run)

[Xtek]

This happens in my S6 as well. Also happened in my C7 A6.

The dealer said it had to do with coolant running through the lines or something. They added some noise damepning and it got rid of most of the noise.

[djpill]

This happens in my S6 as well. Also happened in my C7 A6.

The dealer said it had to do with coolant running through the lines or something. They added some noise damepning and it got rid of most of the noise.

At least I am not the only one that hears this. It's so annoying. Where did they add noise dampening?

[A U D I]

Does the noise come right back as soon as you push the A/C button if you wait a minute or 2 before doing so ?


Sent from my iPhone using Audizine mobile app

[MikeDwerks]

Assuming we are hearing the same noise, had it both on my A6 and current s6. Brought it up to the dealer in my A6 once and they did something, can't recall, and it seemed better for a period of time but came back. Just living with it on the S6

[yeuchau]

Mine doesn't have those humming noise, but instead this type of noise coming from behind he center vent.
Can only hear it when AC is low, anyone has any idea on what this is?
I complain every time when I bring car in for service, but they said its normal everytime.

[MikeDwerks]

Mine doesn't have those humming noise, but instead this type of noise coming from behind he center vent.
Can only hear it when AC is low, anyone has any idea on what this is?
I complain every time when I bring car in for service, but they said its normal everytime.

yep, that is my noise. When I questioned it on my A6 my dealer said it was not normal, and as I stated in my post above, they said they "addressed" it. It did go away for a little while but came back

[SpectreGadget]

Can somebody possibly identify what noise is coming from my AC? Its like a humming sound and it only happens (intermittently) when I have my AC on and it's actually blowing cold air. In fact when it is happening, if I turn my AC button off the sound goes away immediately.
Dealer is struggling with this and my warranty is almost out (although this should be warrantied an additional 12 months due to a prior repair attempt made). The sound is coming from behind the left drivers vent, and they already replaced the vent itself (dumb since it's not a fan issue) and they just did a full recharge of the AC system (freon drain and change).
https://youtu.be/skG8wHZSOis

I can't quite tell from the video, but does it ever sound like a train horn in the distance? Mine seems to do that when the AC is on as well.

[A U D I]

I'm thinking everyone is talking about 2 different noises. The hum noise first asked about and the coolant pipe noise being the second, center vent noise fixed with more insulation to dampen you hearing it.

[djpill]

Does the noise come right back as soon as you push the A/C button if you wait a minute or 2 before doing so ?


Sent from my iPhone using Audizine mobile app

I don't think the noise comes back immediately after I push the AC button back on since the issue is intermittent. It does eventually come back. When i turn the botton off, the noise stops immediately.

[A U D I]

I don't think the noise comes back immediately after I push the AC button back on since the issue is intermittent. It does eventually come back. When i turn the botton off, the noise stops immediately.

I would think it then to be connected with something on the evaporator or hard lines inside the car. Even a label or insulation that had moved causing the hum sound to come through the vent. This would also be why it comes and goes.

[yeuchau]

so I took my car in for service and complain about the AC noise from the center dash, and was told that many A6 customer complain about this before.
They check and found nothing and told me the noise was normal from A/C water condensation.

[Culi]

so I took my car in for service and complain about the AC noise from the center dash, and was told that many A6 customer complain about this before.
They check and found nothing and told me the noise was normal from A/C water condensation.

Someone in another forum posted a reference to TSB:2044717/1 that fixed their AC noise and took a screen shot of the work order. Maybe ask Audi if they can check against that TSB number.

[yeuchau]

Someone in another forum posted a reference to TSB:2044717/1 that fixed their AC noise and took a screen shot of the work order. Maybe ask Audi if they can check against that TSB number.

ok, so I just called the service advisor up and told them I was searching on the forum for this issue and found the above TSB, he looked into it and said he will talk to Sales/manager or someone and see if that be be done under good well (since it's likely not covered under CPO).
hopefully he calls back and said they can do it.

[yeuchau]

so i took my car in again for this TSB, and they did it.
TSB 2044717, they replace the low side A/C Line with balance weight, flush the A/C compressor, replace all O-rings, recahrge the A/C System.

so, for anyone that have similar noise, make sure you complain enough for them to fix it.

[quad_drive]

Thanks for the update... I have the same noise for years...

[Culi]

so i took my car in again for this TSB, and they did it.
TSB 2044717, they replace the low side A/C Line with balance weight, flush the A/C compressor, replace all O-rings, recahrge the A/C System.

so, for anyone that have similar noise, make sure you complain enough for them to fix it.

Was your car still under warranty? If not, how much did it cost? I'm guessing this SB would be expensive to do if you're out of warranty.

[yeuchau]

Under CPO, so I didn't pay anything.
That's not a cheap job.

[fantaxp7]

So I have a humming noise, only seems to happen when the heat is on. I've also noticed it intensifies with my sun roof cracked open.

Very strange noise