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mgb
02-13-2007, 08:50 AM
Folks, I'm getting a headache and a pain in my ears whenever I drive my '07 530xi. I've tracked it down to an extremely high frequency buzz coming from the speakers. It varys in intensity while I'm driving, but it's still there when I stop the engine.

At first I thought it was an air pressure problem, but continued investigation has led me to the sound system. The buzz is there whether the climate control system is on or off. It doesn't matter if the (Business CD) stereo is muted or not, or which input it is selected. However, when I turn the engine off, pull the key and wait for about 40-50 seconds, I hear a click from under the dashboard, a electronic pop from the speakers and it all goes away.

Based on the fact that BMW assist is tied into the speakers, as well as the phone system, I'm assuming that the power amplifier is always on, so if it were defective or improperly grounded, it could cause this problem. I believe that is what's turning off about 40 seconds after I pull the key.

At this point, what I'd like to do is pull the fuse on the power amp, and see if that helps. Maybe I should pull the fuse on a couple other things as well. Problem is: a) I haven't found the trunk fuse box yet and b) there are 6 or 7 fuses described on the fuse card as being related to the stereo.

BTW: In the front fuse box there are two fuses labeled for the stereo. Pulling the first (18) shut down the full instrument cluster and the IDrive, but the high frequency buzz remains. Pulling the 2nd (34), only shuts down the IDrive, but the buzz still remains.

I had a 2007 530i loaner for 3 days, and there was no such problem, so I know this is not a problem with all 530's!

Any suggestions?

(This is cross posted in E60.net (http://forums.e60.net/index.php?showtopic=36802#) - don't know how many people are reading both furums :).

bargamon
02-13-2007, 10:44 AM
Why not just take it to dealer?

mgb
02-13-2007, 02:28 PM
Why not just take it to dealer?

I will, but I'd like to be able to tell them exactly what's going on, so they don't do this :rofl: and send me home like this :mad:

GolferEngineer
02-13-2007, 04:00 PM
My educated guess, being an electrical engineer and having experienced these problems numerous times over the years, is that it is a wiring problem. Probably a bad ground or other faulty connection. You're luck in that it is reproducible. The dealer should have no trouble fixing it. However it may take them a while to find the culprit.

I'm curious: How old is the car and did this suddenly appear one day?

Good luck!

Jalli
02-13-2007, 04:07 PM
agree with everyone else..bad ground..

I'm just an experienced slacker though...

mgb
02-13-2007, 04:23 PM
I'm curious: How old is the car and did this suddenly appear one day?
Good luck!

It's a brand new car, built in December '06. It's been this way since I drove it off the lot in January, but it has taken a few weeks to really appreciate how irritating it is, and to discover that other 530's don't have the problem. :cry:

GolferEngineer
02-14-2007, 05:23 AM
It's a brand new car, built in December '06. It's been this way since I drove it off the lot in January, but it has taken a few weeks to really appreciate how irritating it is, and to discover that other 530's don't have the problem. :cry:

Thanks for the reply and I hope the service folks fix right the first time. Make sure you have someone in the car from the service area when you pick up the car to make sure it is fixed.

Also, you may want to demonstrate the problem when you drop it off - before they drive it away to the garage.

Again, good luck and keep us posted.

BMWNA
02-23-2007, 11:39 AM
Folks, I'm getting a headache and a pain in my ears whenever I drive my '07 530xi. I've tracked it down to an extremely high frequency buzz coming from the speakers. It varys in intensity while I'm driving, but it's still there when I stop the engine.

At first I thought it was an air pressure problem, but continued investigation has led me to the sound system. The buzz is there whether the climate control system is on or off. It doesn't matter if the (Business CD) stereo is muted or not, or which input it is selected. However, when I turn the engine off, pull the key and wait for about 40-50 seconds, I hear a click from under the dashboard, a electronic pop from the speakers and it all goes away.

Based on the fact that BMW assist is tied into the speakers, as well as the phone system, I'm assuming that the power amplifier is always on, so if it were defective or improperly grounded, it could cause this problem. I believe that is what's turning off about 40 seconds after I pull the key.

At this point, what I'd like to do is pull the fuse on the power amp, and see if that helps. Maybe I should pull the fuse on a couple other things as well. Problem is: a) I haven't found the trunk fuse box yet and b) there are 6 or 7 fuses described on the fuse card as being related to the stereo.

BTW: In the front fuse box there are two fuses labeled for the stereo. Pulling the first (18) shut down the full instrument cluster and the IDrive, but the high frequency buzz remains. Pulling the 2nd (34), only shuts down the IDrive, but the buzz still remains.

I had a 2007 530i loaner for 3 days, and there was no such problem, so I know this is not a problem with all 530's!

Any suggestions?

(This is cross posted in E60.net (http://forums.e60.net/index.php?showtopic=36802#) - don't know how many people are reading both furums :).

I'm with BMW of North America, LLC. I've passed this message on to a BMW NA Customer Relations Representative who will be in touch with you soon.