[IllLojik]

So my music suddenly cut out a few days ago. Head unit works, speakers are fine. I automatically assumed "shoot, there goes the amp "
Dug around in the trunk this morning and tested the power/ground with a digital multimeter. NO juice in the power lead to amp. Hmm, Lets test this:
I splice a wire into the amp's power line and run it directly to the battery. Guess what, We have Sound. Checked glove compartment fuses. Nothing wrong in that department. Is there another fuse box somewhere? Where the heck does the amp get it's power from if it's not coming straight off the battery?

Please help. Thank you in advance.

[fdriller9]

I don't know where the REM lead is on the amp harness but behind the HU, it's pin 13. Maybe see if that has power.

I think there are fuses in the engine bay but I really doubt they are connect to the amp.

The amp is probably on the same fuse as the iDrive/HU.

[IllLojik]

Originally Posted by *********

I don't know where the REM lead is on the amp harness but behind the HU, it's pin 13. Maybe see if that has power.

I think there are fuses in the engine bay but I really doubt they are connect to the amp.

The amp is probably on the same fuse as the iDrive/HU.

Thanks. The input is appreciated. I'll check the engine bay tomorrow. I have the non idrive system. (330i Sedan).

[fdriller9]

^regardless, the REM lead is pin 13 on the back of any OEM HU.

[Technic]

There's no remote signal wire going into a Logic7 OEM amp. It turns on by MOST message.

Check the fuse, don't do any splicing of the 12V or this will be worse.

[IllLojik]

Originally Posted by Technic

There's no remote signal wire going into a Logic7 OEM amp. It turns on by MOST message.

Check the fuse, don't do any splicing of the 12V or this will be worse.

You're right. I'm not even looking for a remote wire. I need to know where the stock amp's power line leads back to. The fuse for the radio is good. (Radio works). Any other fuses I should look at?

[IllLojik]

Found the ECU box up front under the hood. Lotsa crap that's hard to get to. There's a tiny fuse junction box within that. I suppose the fuse is in there. I'll figure it out when it's NOT damn near 20 degrees out.

[ctuna]

http://www.e90post.com/forums/showpo...0&postcount=14

This is behind the glove box I think

[blubyu]

take it to the dealer.. DOn't do this.. OMG, you cut a wire.. OGGZZZZZ!!!!11!

[TEKNIQUE82]

did you ever find out what was wrong with your car? I'm having the same problem

[IllLojik]

In my case, it seamed like a fuse was blown. More specifically the feed off the distribution block iirc. I circumvented BMW's crappy setup by wiring the amp to it's own fused power source along with my own aftermarket amp. This way if anything goes wrong, it doesn't interfere with the rest of the radio stuff. Worked out well for almost 2 years before my car was totalled.

[hboss1217]

did you know what fuse was blown exactly?

[IllLojik]

Don't remember. Especially since as mentioned above, I just bypassed the circuitry and wired directly to the battery.

[E9O09]

Hey guys I don't have any power coming into my amplifier harness, I first tired using the bus most but that didn't work, my Idrive works I'm able to use my Navi there's no sound, n there's a sos malfunction.
This happened after I picked up my car from the dealer after getting a recalls done any idea what it could be?

[ctuna]

Maybe they didn't hook the Most Bus test/access point back
up.

Also possible they depleted the battery and the IBS is turning
off power to what it considers not necessary to keep the car
running with a low battery.

Shouldn't they fix it if they broke it.

[hunters335xi]

Did you find a solution to this? I have the BMW professional sterio and logic 7 amp. Headunit wont turn on and the amp is not getting power. Please help!