Knocking noise - air con related?

[tomjj]

Hi,

I've noticed on my car there is a knocking noise coming from the front left like behind or slightly underneath the glove box general area. I'd liken it to the noise you get when tapping a large hollow metal casing.

I've been trying to notice when this happens. It only happens when the car is cold (so when i start out in the morning) and only happens when the climate control is on.

If i press the 'off' button the noise immediately goes.

So it looks related to that. I did read on here it might be the air diverter mechanism or maybe this is something completely different.

Any ideas? Car is due for a service soon so i want to mention it but i want to be confident in what it actually is first in case i can fix it cheeply.

Thanks.

[Ben]

mention the knocking. also mention the words "climate control ecu update" precede these with "will you please check for a"

[tomjj]

mention the knocking. also mention the words "climate control ecu update" precede these with "will you please check for a"

Thanks will do. I presume they will do this on the cheapest £99 service?
What's it do - will it fix my issue?

[damisnang]

Iv also noticed it with my golf.. But i found the noise was comming air intake housing behind the right hand side of the front grill. This was vibrating everytime the air con fan kicked in.