[Nemsys]

Hey all,
I have an 07 335I Convertible with iDrive and the Logic 7 setup.

For the past few months I have noticed that in the middle of a song (can be radio, cd, aux) suddenly there is no bass from any speakers.

Sometimes it might start again in a few seconds and not happen for several weeks again. (I first thought my iPod cable was loose). However, it has been very hot and the last three days it has gotten much more pronounced where there where be no bass for 10 mins at a time. Turning the car off and waiting awhile and turning it back on sometimes fixes it. Sometimes just turning the sound off and waiting fixes it. Sometimes it does not.

When the subs cut out, there is NO change to the rest of the speakers.

When it is working it is very strong and sounds like it did when I got the car.

Is it likely to be the amp it self? Is it just overheating? (its been 95+ here outside temp lately). Possible loose wire? Something else?

I am out of warranty so it is $150 just for the dealer to diag the issue (and since it is intermittent they probably will not find anything wrong).

Suggestions?

Thanks all!

[Technic]

Originally Posted by Nemsys

Hey all,
I have an 07 335I Convertible with iDrive and the Logic 7 setup.

For the past few months I have noticed that in the middle of a song (can be radio, cd, aux) suddenly there is no bass from any speakers.

Sometimes it might start again in a few seconds and not happen for several weeks again. (I first thought my iPod cable was loose). However, it has been very hot and the last three days it has gotten much more pronounced where there where be no bass for 10 mins at a time. Turning the car off and waiting awhile and turning it back on sometimes fixes it. Sometimes just turning the sound off and waiting fixes it. Sometimes it does not.

When the subs cut out, there is NO change to the rest of the speakers.

When it is working it is very strong and sounds like it did when I got the car.

Is it likely to be the amp it self? Is it just overheating? (its been 95+ here outside temp lately). Possible loose wire? Something else?

I am out of warranty so it is $150 just for the dealer to diag the issue (and since it is intermittent they probably will not find anything wrong).

Suggestions?

Thanks all!

Remove the grey plastic cover on top of the OEM amp, let more air into the OEM... rinse and repeat. If the problem goes away or it is much less frequent then I would suggest a custom small 12V fan on that cover.

If the problem does not goes away then the heat really messed your OEM amp internals up and it is not coming back to normal.

[Ron1n]

Originally Posted by Technic

Remove the grey plastic cover on top of the OEM amp, let more air into the OEM... rinse and repeat. If the problem goes away or it is much less frequent then I would suggest a custom small 12V fan on that cover.

If the problem does not goes away then the heat really messed your OEM amp internals up and it is not coming back to normal.

The AMP that comes with the car seems to heat up pretty quickly. I'm constantly hearing the AMP fan on when I go to the trunk after driving. Thankfully, I haven't had the same problem he's had, but it sure does seem to run hot.

[Nemsys]

Originally Posted by Technic

Remove the grey plastic cover on top of the OEM amp, let more air into the OEM... rinse and repeat. If the problem goes away or it is much less frequent then I would suggest a custom small 12V fan on that cover.

If the problem does not goes away then the heat really messed your OEM amp internals up and it is not coming back to normal.

Ok, I failed at finding a diagram of where the amp is in the car. There are three boxes (one with a fan) easily accessible under the partition in the floor of the trunk. However, a few posts here seam to indicate that the amp is in the left rear section. I spent some time trying to remote it (unsuccessfully). Does anyone know if the amp is the unmarked top left box? If not, are there any tutorials on how to gain access?

On a side note, I am going to go with overheating as it was cooler this morning 78 degrees and I had no issues this morning.

Thanks for the replies.

[Technic]

Originally Posted by Nemsys

Ok, I failed at finding a diagram of where the amp is in the car. There are three boxes (one with a fan) easily accessible under the partition in the floor of the trunk. However, a few posts here seam to indicate that the amp is in the left rear section. I spent some time trying to remote it (unsuccessfully). Does anyone know if the amp is the unmarked top left box? If not, are there any tutorials on how to gain access?

On a side note, I am going to go with overheating as it was cooler this morning 78 degrees and I had no issues this morning.

Thanks for the replies.

There is only one grey plastic cover in your trunk, on the left side corner. Remove the cover (just pry it) and you will see the amp.

[Nemsys]

It would appear that the two fans are not spinning up or seized. After driving home in 94 degree weather without the grey cover, the amp was too hot to touch, but using a flashlight and creatively getting my head in the trunk, I was able to see that the fans were not spinning.

I searched a bit, and the only close I can find was someone selling what looked like a CPU case fan to be bolted to the cd changer bracket above the amp, although I didn't see where they would be pulling power from (obviously it is there though).

Any suggestions on the best way to proceed would be appreciated.
Thank you for the feedback so far - I think I am getting closer.

[trk06]

Originally Posted by Nemsys

It would appear that the two fans are not spinning up or seized. After driving home in 94 degree weather without the grey cover, the amp was too hot to touch, but using a flashlight and creatively getting my head in the trunk, I was able to see that the fans were not spinning.

I searched a bit, and the only close I can find was someone selling what looked like a CPU case fan to be bolted to the cd changer bracket above the amp, although I didn't see where they would be pulling power from (obviously it is there though).

Any suggestions on the best way to proceed would be appreciated.
Thank you for the feedback so far - I think I am getting closer.

I hate to say it but your amp need replacement. same thing happaned to me. i gradually lost speakers. first started the cutting-out later some speaker dont work finally i had only the center dash speaker and driver side door speaker working. .
Just got a new amp replaced it. now everything working like before. let's hope all good.

[805beemer]

I have the logic 7 also and my subs haven't been working for the past month or so. Also it seems like i have to turn up the volume more than i used to. I'm still under warranty, what is bmw's policy on replacing audio components? Are there any wires under the seat that my have come loose or been damaged that i can check?

[fdriller9]

If you're fans are not working, that is an easy fix.

Any audio shop or even a computer shop can do it.

[Rudeja]

WOw, i just saw this thread, I have a 08 335i with logic 7 and my Amp cut in and out also, I thought I had a blown Amp but after reading this I see that Its BMW issue. gonna hit the stealership tomorrow to see if I can get it replaced

[darkevo]

how much was the new amp?

Originally Posted by turk06

I hate to say it but your amp need replacement. same thing happaned to me. i gradually lost speakers. first started the cutting-out later some speaker dont work finally i had only the center dash speaker and driver side door speaker working. .
Just got a new amp replaced it. now everything working like before. let's hope all good.