I installed a replacement OEM Becker radio in my 300D (the replacement Becker came from an '87 190E). There is one blue wire that comes out of the radio that doesn't seem to have a mate on the car side. This wire is light blue and is seperate but located right next to the plastic connector with the 4 contacts.
The power antenna is not extending, so is this maybe the wire that activates the power antenna?