I'm almost embarrassed to ask these questions, but I'm at a loss as to how to proceed, and my car audio experience has been limited to common sense hookups or replacing faulty components; never having much to do with re-wiring. I'm not an audiophile and so when I bought this car, was content that when I turned the radio on I got sound, nor was I particularly concerned that the antenna was stuck up, since here in Minnesota a working mercedes antenna is the exception rather than the rule. But... This old Becker Europa no longer tunes properly either with the buttons or the dial, the cassette drive doesn't work, sound only from the front speakers and the antenna motor is dead. So all I want to do is replace with a functional radio, have all the speakers work, and if a check of the power antenna shows it to be functional, then swap the mast as I've had to do with every other Benz I've owned.

Here's the gist of the problem. When I pull the radio, there are so many wires stuffed behind it is hard to get the unit back in. I'd guess judging from all the electrician's tape, splices, open wires and such that on at least two occasions an amatuer (like me) has installed aftermarket components by splicing both onto the original harness or a previous splice, pulled them when selling the car and the next owner doing the same so that by the time I got the car, an old radio was stuck back in with no real effort to hook it up properly.

So here are the questions:

1. What is the best way to determine which of these many speaker wires are the ones now connected to the rear speakers?

(hint, there are two sets of wires with one black and one white capped connection that plug into the radio. But on this radio there are connectors only for one set. Thinking the unplugged set was for the rear, I swapped them losing sound from the front but not getting anything from the rear. And there are 2-3 more sets of disconnected speaker wires, to choose from.)

2. Reading other threads I get the sense that there are three key wires to the power antenna, trigger, constant and ground. Given that there is only a hot wire and the antenna cable now connected to the radio nor does the dash up-down switch do anything, how do I identify these wires, and test for continuity? If this is a big hassle, I'm ok with just pulling the power antenna and installing one of those manual rubber ones.

Remember there are multiple splices and splices of splices using whatever wire was handy so that color coding is of little help.

3. Sort of related since this is in the same place, I wanted to plug my cell phone charger into the cig lighter, but find that the leads have been disconnected and the female spade connectors are no longer hanging off the end of any of the open wires back there. Does it matter which of the male connections is hot or ground and how I reconnect?

4. I also have a suspicion that the reason the interior dome light doesn't come on with either door open, but does with the dash switch is related to this mess too.

Related to all this, either I just can't read, or the harness schematics in the Chilton manual do not show dome, radio or cig lighter connections.

Help??

Not sure if this will help, but it may give you a rough idea. Mine is a Becker Grand Prix BE2140 with an Alpine 6CD Changer hooked up. In this link -

http://www.peachparts.com/shopforum/showthread.php?t=240513&page=2&highlight=cassette+stuck

you'll see a pix of the rear of the unit with the wires attached. Unfortunately, I do not have a power antenna. Mine is a fix metal rod which is up all the time. Next pix shows all the wires which are NOT connected and left "hanging' behind the unit. The unit is working fine so those loose wires are I suppose meant to be loose.

Sorry I can't be of more help.