[accetturo]

My 2006 325xi is not giving me any base from under seat subwoofers. It just seemed to stop working completely. I've browsed around but the way BMW does the sound system is different from most cars I've seen. There seems to be no fuse for the subs. On my head unit it says BMW Professional. It also has a mesh panel where the tweeters should be and it has something that looks like an amp under a panel labeled cd in the truck driver side. I'm assuming I have a hifi unit then? There is a very low volume coming from the sub under the driver seat and it is distorted with a bass buzzing. No volume or bass from under the passenger. Idk if there way a bass under the passenger, from what I've already read online it seems there should be a subwoofer under the passenger seat but I think that one may have blow before the driver. Possibly causing to much power drain from the driver. The driver side is still working barely. Please help me fix this problem. If it is the subwoofers blown, please provide me with some easy replacement subs. If its the amp please provide some replacements. I seen online some people are replacing there subs with SwS-8, how difficult is that to do and can I use the 8xi, and how much of a sound improvement is that.

[accetturo]

Here is some pics so I can help identify my system. One of the truck driver side under "cd" panel. Another of driver side door and one of head unit

[ctuna]

See this thread if you want to modify

http://www.e90post.com/forums/showthread.php?t=641323

Do you think your amp got wet.
Its pretty dirty in there.

[accetturo]

I'm just looking on suggestions of the issue. I'm not ness army looking to upgrade just looking to fix the issue. Sometimes though with the cost of BMW oem parts its cheaper or the same cost to put in better parts, so I'd like help diagnosing whether it's the amp or subs or how to diagnose them, Which ever is broken I'd like basically a plug and play solution to fixing them.

[ctuna]

Speaker resistance from the amp could be measured.
You would need to look at the wiring diagram and disconnect the amp
at the amp connector.
then measure the resistance from the amp connector for each speaker.
Other than that you could sub another known good BMW Hi Fi amp.

Under seats will measure about 2 ohms from the amp connector .

http://www.e90post.com/forums/showthread.php?t=138949

There are two 8 inch underseats one on each side . I would try adjusting the fader all the way foward and then putting the balance all the way to one side to check that side then do the same for the other(put on something you know had heavr bass when you do that and turn it up if you can). That system does not have very strong bass to start with.

[wilbur_the_goose]

Like the earlier post said - your amp is really dirty and there should be no reason for that. You may well have a leak in there. If so, you'll obviously want to fix that first.