My '06 had it in the back glass. Earlier ML's had antenna integrated with rear window defroster. I believe it was separated in the W164. It's possible there's a cable loose, either on the back of the comand or in the hatch.

 

First place to check would be the FM rear window antenna amplifier (A2/19) located behind the tailgate liner. You will be able to check the connections to the window antenna.

It is unlikely that the antenna in the glass is damaged.

 

A2/19 what is that, a part number?

I removed the very top panel and the panel near the buttons to lock and open/close the tail gate. I don't see anything resembling an amplifier, just the windshiled wiper hose and some wire seemingly grounding something to the door. Is this amp in the very middle of the door?

 

We do not know what audio features your car has. Why not suspect the radio itself..? Does it light up? Do other audio units (CD?) work? A few fuses to check.

F3 - cockpit fusebox:
fuse f15 (5A) media interface control unit.

F4 - load compartment fuse & relay box:
fuse f20 (5A) radio antenna interference filter
fuse f25 (5A) COMAND
fuse f35 (30A) sound system amplifier

 

The radio works normal other than weak signals, when the guys of this site indicated that the amp is at the back panel it made since that it may get damaged because I load things back there weekly. I'll check the f20 fuse to see if that is the cause, thanks.

 

An intermittently working radio is not going to be a fuse problem. Check for loose connections.

 

An intermittently working radio is not going to be a fuse problem.

True - but that is not how this question started out...

 

Well guys I've pin pointed the problem to two things. Either my new power cord I have charging my phone or the Bluetooth antenna is causing interference. I believe its the power cord because once I pull the power cord from the phone the distant channels work fine.