This modification are for those members that are looking for the addition of an Auxillary input in their R171 SLK with A20 stereo without COMMAND.
Got this modification from information provided by fellow SLK'ers on another forum. I tried the mod and it works flawlessly and is pretty easy to do. If you have any soldering ability at all than you should be able to modify your A20 basic radio and create an inexpensive Auxillary input for your Satellite radio or MP3 player. The Link provided are pictures of it while I was doing. It essentially does the same as some of the after market systems available out there at a fraction of the cost. If you try to do this modification you do so at your own risk. Special thanks to Ikarus who found the original mod on the german slk forum and pointed me to it.
Remove the A20 Radio as per instructions elsewhere on the site.
Bill's Den: Documents
Read through Procedures "Retrofit iPod", pictures useful for dash disassembly.
Pop out center console around stick shift and disconnect to plugs attached to it.
Lift center panel and get it out of the way.
Remove cover over lighter by putting small screw driver in on drivers side and pry gently up and towards passenger seat.
Remove small cover on left side to reveal screw and remove screw with #20 Torx screw driver. Pull ashtray assembly out. Pop out heating assembly.
remove screws holding flasher assembly and remove. Than remove the cup holder assembly above the radio by removing rubber covers on either side to reveal screws.
Now remove the four screws holding in the head unit and remove the rear cable assembly and antenna.
Now take the A20 and remove the screw on the top and the two screws holding the top cover on the back. Remove the top and then all you have to do is solder two wires to the printed circuit board as indicated by Ikarus. The ground or common is just one of the screws on the back holding the back plate on. No need to solder the ground just tighten it down.
I then fed the wire through the back of the back plate and put a female Stereo RCA jack on the back so that if I have to remove the radio all I have to do is unplug it instead of removing all the wiring.
Then I just ran a RCA cable from the unit to my Satellite/MP3 player tested and closed everything up.
Now you have to format a CD-R ( at first I just put a CD-R in straight from the package and it would work for a minute and then give an error message of "wrong CD"!!! Went and formatted the CD-R plugged it back into the front of the A20 and everything worked and sounded awesome.
Sirius sounds great even with the amount of compression they use. My MP-3's sounded as good as any CD. No noise and dead quiet.
The install was way easier than installing the Smarttop. I have pictures and they can be found with captions at the link below. For a few bucks you can have a seperate Aux-input on the base A20 head unit without Command.
Picasa Web Albums - Dr. Jory C. Still... - A20 AUX-Input... KUDA mount and holder MERCEDES - SLK R171 (since 2005)
If you have any questions or want any other shots of the mounting unit let me know.
Thanks again for all the help.
Linear Mode
