Installing a Becker BE 980 CD Changer in a 92 300CE
This blue paper chronicles the installation of a Becker BE 980 10 disk CD changer (OEM) in a 1992 Mercedes Benz 300CE with a Becker 1432 two part system "pre-wired" for an integrated cellular phone and CD changer. This installation is probably typical for other years and models but I can not guarantee it. I've learned a lot and want to share my new found knowledge in hopes you won't have to go through what I did. If you have all the parts & pieces before you begin, it is a two - three hour job.
Becker Board - http://www.insidetheweb.com/mbs.cgi/mb1053979
Data, Interface and Power Cable
You will need a Data/Power cable to connect the 1432 tuner/amp (in the trunk) to the BE 980 changer. The cable I used is Mercedes Benz part #BQ6 82 0175 for $98.00. It's a 3 part cable and consists of a Y-cable for power and two gray data cables. MBZ will tell you it's not the correct part, and if it's not, it works. They also told me I needed two additional "interface" cables part numbers BQ6 82 0174 and BQ6 82 0135 but I did not. Mercedes used a 6 disk Alpine CD Changer in addition the 10 disk changer that may have required these cables and I do see a reference to an interface unit for the Alpine unit in the MBZ W124 Service Manual.
As I understand it, the original MBZ CD changers were housed in a "shell" that sat in the right trunk well/pocket. The local MBZ dealer told me this shell and carpet kit are no longer available for the 1992 CE but they are available for the 93 CE - which make no sense to me at all. Not being able to actually see one, I gave up and started looking for a mounting bracket of some sort. I e-mailed all the Becker dealers listed on Becker NA's web site and came up with a bracket from Walter Odemer, Inc in Burbank CA. for $85.00. http://www.primenet.com/~odemer/index.htm
Mounting Bracket Screws
Go to the hardware store and buy four of the shortest metric bolts you can find with the same thread pattern as the shipping screws. You will need these to mount the BE 980 to the bracket.
CD Changer Magazine
The BE 980 changer uses the Sony XA-10B magazine. I searched the web and found them at Crutchfield for $29.95.
Now that you have all the parts for the install, LET'S GO! The tuner is mounted on the right side (looking in) of the trunk just aft of the fuel filler. Look near the trunk spring, this is where you'll be working.
Of course, the first thing you SHOULD do is disconnect the battery. I'm careful so I didn't.
Remove the trunk carpeting - the floor and vertical piece against the back seat.
Remove the right molded-fiber trunk liner piece. It takes real patients to get this out in one piece. After several minutes of wrestling with it, you'll want to rip it out in several pieces but go slow… work it out. It does come out and go back in one piece.
While you have the liner out, try to envision where the CD changer might mount in the trunk pocket and cut a hole in the bottom of the molded-fiber trunk liner for the 3 cables.
With the trunk liner out, you can see the tuner with a gray DIN type data cable and multi colored power cable. Before making the connections, print this cabling diagram for a better idea where things go. My tuner has two DIN type receptacles - the second receptacle remains unused. Unplug the gray cable from the tuner and connect it to the female end of the new 3 cable set (one is a female). The other end of this cable goes into the receptacle on the BE 980 marker FRONTGEROL (front unit) but don't connect it now because you have that #*!!* trunk liner to get back in place first. What you're doing is extending the buss for the audio system so it stops at the CD changer and then the tuner.
As you might imagine, the other gray cable (male) at the tuner end connects to the same receptacle you unplugged in step #5. This is the return data run from the CD changer to the tuner.
Disconnect the power connector from the tuner and reconnect it to the female connector of the Y-power cable in the 3 cable set. Then re-connect the only remaining male power connector (at the tuner end of the cable set) to the tuner.
You have now completed all the connections at the tuner end. Make sure the cables are nicely tie-wrapped away from the trunk spring and anything else that moves. Coil the 3 cable set in the trunk pocket and get ready for more fun.
At this point, you may want to jump to #12, #13, #14 & #17 to make sure your connections work before replacing the trunk liner and buttoning everything up like you know it's gonna' work! I highly recommend this step.
Before you start wrestling the trunk liner back in, pull the 3 cable set through the hole you've made in the bottom and then replace the trunk liner.
Before mounting the BE 980 into the bracket, position the bracket in place along the right trunk rail and drill three small holes for self taping sheet metal screws to hold the bracket in place.
Before mounting the bracket to the BE 980, verify the shock stabilization settings are set for a vertical mount.
Now mount the BE 980 to the bracket. Note that the mounting bracket is pre-drilled to use the four shipping screw holes in the BE 980. Do NOT use the shipping screws to mount the changer or you're anti-shock feature of the changer will be compromised.
Connect the gray DIN type cable marked "CD-Wechsler" to the "FRONTGEROL" receptacle on the CD changer (you connected the other female end of this cable to the male that runs to the head unit in the dash).
Connect the other gray DIN type cable to the other receptacle on the CD changer marked TUNER (you connected the other end of this cable to the tuner).
Connect the power cable the CD changer.
Mount the bracket with the BE 980 on the trunk rail using the three sheet metal screws.
Replace the trunk carpeting - vertical piece against the back seat first then the floor piece.
Fire it up and give it the smoke test. If you did everything right, you'll now have a third MODE on your head unit for CD and a Factory CD Changer (almost).