radio/nav wont turn on

[Reed_HSE]

I cant get my radio or nav screen to do anything, ive tried disconnecting the battery to reset it and checked all the fuses but still nothing, took it to the dealer and they said it could be the head unit but they recommended trying the phone module, i have never even heard of this. Does anybody know about this module or even where it is located in the car. Sounds expensive.

 

[GMTIIFAN]

I had a similar issues with radio a while back. Basically the radio was lit up, but no sound regardless of what mode. Dealer had to replace it. I have an 05 se7 and actually had the radio issue twice and radio was replaced both times.