Can I just disconnect my antenna?
 

I have the sharkfin antenna, and since I NEVER listen to the radio (especially because it's in Italian), I thought about disconnecting mine. I have no built-in Bluetooth support, so I purchased a FM Bluetooth modulator, which works great...however there are SO MANY Italian stations that there's NO open channels. 0. The closest I have is 87.7 but it is still picking up some weak signal from some radio station somewhere. I just want to disconnect the antenna somehow, so I can plug up and listen to music from my phone.
Car is a 2005 525d touring.
Any insight? Will this affect the NAV system?

Thanks guys!

Your radio antenna is not in the shark fin, it’s in the rear window glass. Under the rear spoiler there is a wire for it but disconnecting will likely affect your keyless entry as if I’m not mistaken, that antenna sends its signal to CAS through the same coaxial line. If you remove your antenna I highly doubt your FM modulator would work at all since I find they usually have very weak signals.

no aux input on the car that you could plug a Bluetooth adapter into?

Let me clarify...its an FM BT transmitter (not modulator) aka the little ones you plug into the cig lighter outlet...so in theory if I disconnect the antenna, the channel itself should be "open" because it isn't pulling a signal from the radio station tower (no static) & the BT transmitter should play w/no interruption . My keyless entry doesn't work & I'm not really in a rush to fix it.

Unfortunately, no aux input (I was pretty disappointed in that)...because I am sure I at least have the BT option because it has the OEM phone cradle in the center & I have the opyion to pair phone...but for whatever reason it will not pair with my iPhone. I'll have to take a photo and post it so you can see what I'm referring to.

Yes, that is exactly the kind of device I'm referring to. All it is doing is broadcasting on an FM frequency so if you disconnect the antenna on your car it not only makes it harder for your radio to hear other stations, it makes it harder for your radio to hear your FM BT transmitter's broadcast. But if it ends up working for you, that's awesome. In my own personal experience with those FM transmitters, they are so weak that even with a properly working antenna they only work if properly oriented inside the vehicle itself. Give it a try, you might have success, it's easy enough to disconnect the antenna in the rear spoiler, or you could even disconnect the power wires going to the antenna amplifier in the spoiler since you don't use the keyless entry anyway.

I believe the sharkfin only houses the GPS, cellular, and TV (if you have it) antennas.

In reference to the BT issue:
https://cimg8.ibsrv.net/gimg/5series...5d9d64719a.jpg
https://cimg6.ibsrv.net/gimg/5series...0f0e1e0bcc.jpg
https://cimg5.ibsrv.net/gimg/5series...a2102eb67d.jpg
https://cimg4.ibsrv.net/gimg/5series...283a519c6a.jpg