e38 audio problem

[Docile 64]

hey guys , i noticed that my factory subs stopped working on my e38.. anyone had this problem before?? anyone know how to take out the subs?? or where the amp is... i've tried all i can with the controls up front but still no subs firing like it used to... prob an amp problem?? pressing the "SB" button on and off makes no difference, putting up da lower frequency makes no diff either..

thanks for the help

[User Name 19]

Hi Mate

have no idea but http://www.e38.org/ have the wiring links etc and sub installation somewhere to start

[jochen 4]

hey guys , i noticed that my factory subs stopped working on my e38.. anyone had this problem before?? anyone know how to take out the subs?? or where the amp is... i've tried all i can with the controls up front but still no subs firing like it used to... prob an amp problem?? pressing the "SB" button on and off makes no difference, putting up da lower frequency makes no diff either..

thanks for the help

Start with the basics by checking speaker continuity.

You can do this easily by unplugging the speaker connector from the amplifier in the boot and measuring the speakers.

I'm assuming you have the DSP amp, because only cars with the DSP amp had the subwoofer system fitted.

But anyway, its the same procedure for all speakers in the car.

And you don't even need the wiring diagram as the speakers are all wired as a paired cable, and it is easy to identify the cable pairs. The subwoofers naturally have the thicker wires...

And remember with the DSP system you have 14 speakers, so quite a few to check.

All 4 subs are wired directly and individually back to the DSP amplifier.

So if all 4 subs failed at the same time, really there's only the amplifier as culprit - unless you blew all 4 subs at the same time!! (if you did this, stop winding up the bass so loud!!)

The sub wiring on the DSP amp on connector A (X18871, 15pin black) is

Sub 1: pins 1 & 9

Sub 2: pins 2 & 10

Sub 3: pins 14 & 7

Sub 4: pins 13 & 6

In each case the first pin number is positive.

And the amplifier is located behind the CD changer in the boot, big metal silver box with heatsinks (fins) on it, and 3 x connectors. Turn key off before unplugging.

Tip: check for water damage! Quite common... look for water marks on the case, check all connector pins are shiny and clean, not green and gunked up.

Edited September 1, 2009 by jochen

[Docile 64]

thanks opening it up now... are the 4 subs the ones on the rear parcel tray??

[Docile 64]

hmmm well hada look see at the amp at the back, took out the connectors looked for dirty connectors but all good... sprayed contact cleaner in it, no water damage and looked at the visible lines for breaks.. but all good.. plugged it back in and started the stereo... the subs are not completely gone.. is just that its so weak [assuming i was testing the right speakers - the 2 speakers under the speaker vents at the rear parcel tray] even on high sub settings... prob blown subs?? but all 4 at the same time???

[jochen 4]

thanks opening it up now... are the 4 subs the ones on the rear parcel tray??

Yep, on the rear parcel tray.

[jochen 4]

hmmm well hada look see at the amp at the back, took out the connectors looked for dirty connectors but all good... sprayed contact cleaner in it, no water damage and looked at the visible lines for breaks.. but all good.. plugged it back in and started the stereo... the subs are not completely gone.. is just that its so weak [assuming i was testing the right speakers - the 2 speakers under the speaker vents at the rear parcel tray] even on high sub settings... prob blown subs?? but all 4 at the same time???

You may have blown all 4 if you were using excessive bass.... you should always listen to the stereo and recognise when the speakers are bottoming out, and then turn the volume down.

Otherwise, you physically destroy the cones.