Runaway/possessed audio system - '09 328i

[Toad1950]

Suddenly and without warning the stock audio system seems to be possessed. The audio amp seems to be on all the time -- even with the car turned off. It pops and cracks loudly with no audio program even after sitting turned off all night. When the car is running and the radio on there's lots of static, the audio is distorted (even the nanny chimes) and it drops out frequently. Tapping the brakes seems to restore the distorted sound, but it doesn't last long.

Ideas?

Tom

[MarcoZandrini]

The amp is bad. It has power at all times but requires a 12VDC “turn on” signal from the head unit to operate. It sounds like it’s staying on even when the “turn on” signal is no longer present. Try eBay for a replacement.

[Toad1950]

Thanks. I'm on a trip several hundred miles from home and the buzzing and popping is extremely annoying. I'd like to pull the fuse for the amp until I can get it fixed. I think I've identified the radio icon on the somewhat cryptic fuse chart. I presume the amplifier is one of the higher amperage fuses on the lengthy list. Any clue which one ('09 E91)?

[MarcoZandrini]

Yeah, BMW is being a real jerk with the fuse panel symbols. I’m in the same boat with my M240i. Jssssh, come on BMW. We are, for the most part, adults.

[Toad1950]

Ha. The icon in the fuse table I've tentatively ID'd looks like both the radio and the climate control panel. There's another one that looks like a larger display panel with no knobs which I'm assuming is the GPS display (that I don't have). I suppose the GPS system talks, so maybe the radio and GPS have a high amp fuse in common....

I don't want to start pulling lots of unnecessary fuses looking for the right one since they look to be a pain to replace.

[MarcoZandrini]

I’m with you! I even called BMW NA to see if they could send me a proper fuse diagram. Ha! They emailed me the same cryptic diagram that I already had.

BMW WTF ARE YOU THINKING? We aren’t all boobs.

[Toad1950]

Okay, I pulled fuse #15, (20 Amp) that seems to be unique to the icon that looks like a radio (two knobs on either side of a narrow dispel panel). I just listened for a minute before I had to park the car, but it seems to have muted the audio amp. The audio display panel's lights are still on, but that's probably a different fuse and is fine by me.