So I bought a 05 545i recently with Mtech package, and it has aux connecter in the glove box which seems to be oem and in the entertainment menu it shows aux but when I plug my phone and play a music and select aux nothing plays or Comes out of the speakers. What would the problem be? And I have tried different aux cables and phones.

 

Have you made sure the mute isn't active and the volume is turned up?

It could be something as simple as a loose connection, or it could be a little more complicated requiring programming, but you stated the 'AUX' was showing in Idrive so I think the programming was done. Just to confirm, when you click 'AUX' on Idrive, does it say 'external audio source' in the main window?

-Matt

 

When I plug it it says "no external Audio can be found"

 

Check the connections to the CCC from the AUX socket. something may have come loose, I believe the CCC auto detects audio signals on the line, and if it does see anything it'll change the display to 'external audio connected'. the cable might be loose or broken and the CCC isn't getting signal.