I found a way to test the Bluetooth antenna: Disconnect the antenna lead from the MULF module, it's the single cable on the right hand side. Place the telephone near the antenna connector of the module and try to pair it with the car. If pairing is successful, but you can't pair with the antenna lead connected that suggests the Bluetooth antenna is bad and the module is fine. But, in my case, I still didn't get the car and telephone to find each other.
Suspecting the MULF module even more, I removed it from the car, took it inside and opened it up. Looking for cracked connections, swollen capacitors and signs of moisture but I found nothing strange. There is a company in Australia (
http://www.bmwbluetooth.com.au/) that repairs MULF modules, do you know if there are any repair guys in Europe? On the other hand, instead of spending AUD 400 for a repaired unit I could get a brand new from schmiedmann.se for GBP 400 / EUR 480 / USD 650.
I had a slightly crazy thought of placing the module in the kitchen owen, to reflow the solder or something. But I have no idea whether that is possible or what temperature and time I should use...
Since my car doesn't have USB or Voice control, my module is the MULF2 LO variant. Is it possible to replace it with a MULF2 HI module? The HI module is actually less expensive than the LO module, "just" GBP 280 / EUR 340 / USD 460.
If I replace the module, will the car need coding?
The part number of my module: 84109149656 (MULF2 LO)
The latest revision of the MULF2 LO: 84109226711 (12 revisions later than my module, I guess they have had some problems with this unit)
The latest revision of the MULF2 HI: 84109229740
If it is possible to replace my LO module with a HI module, I guess it should be possible to mount the other pieces of the USB retrofit kit as well?