The phone bulletin for your car is at https://docs.google.com/file/d/0BxI8...1fQl9IMTA/edit
(it is a web archive, you may have to give permission for it to open). I am assuming that you have all of the equipment shown in the bulletin installed, and your fiber optic controller (often the head unit, or the Audio Gateway if your car's audio system has one) has been version coded for the equipment.
The second post in the thread at https://www.benzworld.org/forums/aud...ades-plug.html
applies to your car. Please note the equipment requirements there. Given that you have an '04, it is likely you already have an autosense PSE.
Please note the comments regarding the cradle size and the V60 puck. If you have an older cradle, it is possible you may not get a proper fit to the contacts of the puck.
The puck provides a Bluetooth connection, and it should work with a Bluetooth phone. I have no idea why a properly installed system with a properly fitted puck would not power up, unless there is a blown or missing fuse of something is malfunctioning in the installed equipment or, if someone had it coded out of your system because of some other problem.
Of course we cannot tell whether what the Mercedes dealer said is "true" - first, we don't know the whys or wherefores of the statement. Second, other than what I have tried to provide here, we have no way to troubleshoot your particular installation.