BMW M3 Audio System Dead, Complete Infotainment Failure

I'm a car enthusiast with some experience in car electronics. I had a similar issue with my 2007 BMW M5 last year. The symptoms were nearly identical, complete DAB failure and infotainment going haywire. After taking it to my trusted workshop, they diagnosed a faulty antenna module. The entire repair, including parts and labor, cost me 255 Euro. The mechanic mentioned these issues are somewhat common in that generation of BMWs (including the M3). Before replacing the antenna, you might want to check if it's just a loose connection, but honestly, in my case, the module was completely dead and needed replacement. The fix completely resolved all my audio and infotainment problems. What's your vehicle's mileage? Have you noticed any other electrical issues? This could help narrow down if it's just the antenna or potentially something more complex in the electrical system.

Thanks for the detailed response! Mine's at 8486 KM since I just got it serviced. Haven't noticed any other electrical gremlins, which is a relief. Will definitely check the antenna connections first before diving deeper. Good to know about the module replacement being a potential fix, I've got a mechanic who might be able to help diagnose it this weekend. Really hoping it's just the antenna module like in your case!

Hey again! Yeah, after seeing your mileage, I'm even more convinced it's likely the antenna module. When I had my M5 issue, it was also pretty low mileage (around 9000 KM) when the problem started. These modules can fail regardless of mileage, it's more about age and exposure to weather conditions. Just a heads up based on my experience, when my mechanic first looked at it, he thought it might be a simple connection issue too. We spent a good hour checking and cleaning connections, but that didn't solve it. Not saying yours won't be a simple fix, but if cleaning connections doesn't work, don't waste too much time before checking the module itself. Quick tip: when my module was failing, I noticed the reception would sometimes come back briefly if I hit a bump in the road, might be worth noting if you experience anything similar. This was actually what helped my mechanic confirm it was the module rather than just a loose connection. Let me know how it goes with your mechanic this weekend. Always interested to hear if others have the same fix as I did!

Thanks so much for all these extra details, especially that tip about the bump test! Now that you mention it, I've actually noticed exactly that happening, the radio occasionally comes back for a split second when going over speed bumps. That's super helpful to know it's a telltale sign of the module failing. You've saved me and my mechanic friend a lot of troubleshooting time this weekend! Will definitely focus on checking the module itself rather than spending too long on the connections. Really appreciate you sharing your experience with this, I'll update the thread once we figure it out and get it fixed. Thanks again for all the help!