DIY Aux-In for Audio 20

Ikarus · 08-06-2007

Disclaimer: I haven't done this myself, but I thought this might be useful info for SLK owners who did not feel like the Command system is worth the extra $$ and now wonder how the heck they can hook up an MP3 player to their car stereo.

On mbslk.de, people are discussing a DIY solution that hijacks the CD audio path of the Audio 20. See here (in German). From what I gather, there needs to be a dummy CD running. One guy says he recorded an audio CD with a flat zero track for this purpose, another says any data CD-R will do. This picture (link updated) was posted for the hardware details. Allegedly, this PCB is accessible from the top of the Audio 20, just by removing the lid, which is held by three screws.

Of course, this doesn't give you fancy features like steering wheel control, but it doesn't cost an arm and a leg either.

VitaminT · 08-06-2007

Seems like I saw something either on here or one of the other forums that plugged inline with the audio 20 harness that you could then plug into your ipod. They were holding down the cdc button and it would play the ipod vs cdc. The cdc still worked if you just tap the button. Not sure it works for everyone though.

Ikarus · 08-06-2007

Quote:

Originally Posted by VitaminT

Seems like I saw something either on here or one of the other forums that plugged inline with the audio 20 harness that you could then plug into your ipod. They were holding down the cdc button and it would play the ipod vs cdc. The cdc still worked if you just tap the button. Not sure it works for everyone though.

I think you mean the Dension Gateway 500. There was a thread about this here. It currently runs about 450 US, and apparently you can get steering wheel controls with iPods using some additional adapters that cost extra. From what I hear, track display is numerical only. I'm not sure that's worth the money, especially since I don't really care much for iPods or iTunes.

**SLKDawg** · 08-07-2007

Quote:

Originally Posted by VitaminT

Seems like I saw something either on here or one of the other forums that plugged inline with the audio 20 harness that you could then plug into your ipod. They were holding down the cdc button and it would play the ipod vs cdc. The cdc still worked if you just tap the button. Not sure it works for everyone though.

You are speaking of the AUX function using the CDC button - doesn't work for US spec SLKs.

**SLKDawg** · 08-07-2007

Quote:

Originally Posted by Ikarus

This picture was posted for the hardware details.

Have you tried this link???

Ikarus · 08-07-2007

Quote:

Originally Posted by SLKDawg

Have you tried this link???

Yes, I had. Someone swapped out the picture, but I've found a copy in my browser cache.

Here you go. Thanks for letting me know.

shpritz · 06-06-2008

Anyone tried this Mod. Seems like an easy cheap solution. Any chance of a english step by step guide on this Mod????

shpritz · 06-06-2008

Could someone please confirm that the english translation for the German word "masse" in the picture is Common Ground / negative?

Ikarus · 06-06-2008

Quote:

Originally Posted by shpritz

Could someone please confirm that the english translation for the German word "masse" in the picture is Common Ground / negative?

Positive! Err, I mean, definitely!

shpritz · 06-06-2008

... Do you know if anyone has actually tried it here. Seems a lot easier and a hell of a lot cheaper than spending the dough for a Dension unit or the iTronic. Looks pretty straight forward and easy if you are handy with a soldering iron....

Ikarus · 06-06-2008

Noone here (including myself) as far as I know, but some on mbslk.de have done it.

I'm finding that music in the SLK is much less important to me than I thought it would be. When the roof is down, which it is most of the time, the signal-to-noise ratio is worse than with grandpa's short wave radio reception anyway.

shpritz · 06-07-2008

OK. I had some time today and did the DIY Mod discussed above. Very simple and easy to do. Easier than putting in the smarttop. Anyhow it works very well but only works for a few seconds with a blank CD-R and than reads it as a "wrong" CD and switches back to the radio (FM). Does anyone know how I go about burning a flat zero CD or what I would do to get the CD-R to continue spinning without the error message. Can use a soldering iron but not so savy with CD-R's

Ikarus · 06-07-2008

Quote:

Originally Posted by shpritz

Anyhow it works very well but only works for a few seconds with a blank CD-R and than reads it as a "wrong" CD and switches back to the radio (FM).

Hmmm, this is odd. A guy on mbslk.de reports he got it to stay on CD with a blank CD-R. Are you sure it's completely blank? Another guy said he's putting in a data CD-R.

**UK-C200** · 06-07-2008

Hmmm - well, if you are computer savvy - create a "silent" wave file, say 10 minutes long.

y that so that you have 6 copies, and then create an "audio CD" with your burning software. If you want help trying this, drop me a pm and I'll see if I can talk you though it.

shpritz · 06-07-2008

OK got it all done and working. Works fantastic. Here is what I did.

Remove the A20 Radio as per instructions elsewhere on the site.
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 hopefully they will upload. For a few bucks you can have a seperate Aux-input on the base A20 head unit without Command.

shpritz · 06-07-2008

Can't get the photos to upload???

**-1-** · 06-07-2008

Quote:

Originally Posted by shpritz

OK got it all done and working. Works fantastic. Here is what I did.

Remove the A20 Radio as per instructions elsewhere on the site.
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 remoce 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 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 hopefully they will upload. For a few bucks you can have a seperate Aux-input on the base A20 head unit without Command.

Great work. Thanks for your effort and contribution and those that assisted. Good luck getting the pics posted.

**-1-** · 06-07-2008

Quote:

Originally Posted by Ikarus

Disclaimer: I haven't done this myself, but I thought this might be useful info for SLK owners who did not feel like the Command system is worth the extra $$ and now wonder how the heck they can hook up an MP3 player to their car stereo.

On mbslk.de, people are discussing a DIY solution that hijacks the CD audio path of the Audio 20. See here (in German). From what I gather, there needs to be a dummy CD running. One guy says he recorded an audio CD with a flat zero track for this purpose, another says any data CD-R will do. This picture (link updated) was posted for the hardware details. Allegedly, this PCB is accessible from the top of the Audio 20, just by removing the lid, which is held by three screws.

Of course, this doesn't give you fancy features like steering wheel control, but it doesn't cost an arm and a leg either.

That's the second great tip from the mbslk.de forum you've provided. THANKS!

shpritz · 06-07-2008

In the mean time I have uploaded the pictures to my Picassa web album and put captions with each photo.

http://picasaweb.google.com/jstillwater/A20AUXInputMOD

shpritz · 06-07-2008

Oh yeah. I want to thank Ikarus

for pointing me in the right direction and saving me a fortune. Had been looking for a while now and just about pulled the trigger on a Dension Unit which with my A20 without command would essentially do the same thing. Honest guys, if you can solder, the mod takes 5 minutes to do. While you have everything apart you can splice into the cigarette light hot and ground to run your power hide the wires and have a seamless install of your Satellite or MP-3 unit. The Kuda mount looks exactly like it is OEM.

http://www.kudausa.com/kuda_mount_an...5-25-254.html#

If you have any questions or want any other shots of the mounting unit let me know. Thanks again for all the help.

08-06-2007	#1 (permalink)
Ikarus Elite SLK World Member Join Date: Jul 2006 Location: NorCal Vehicle: 2006 SLK 280 w. 6M Other Toys: 2000 New Beetle GLS w. 5M Posts: 596 Country: Thanks: 18 Thanked 40 Times in 20 Posts	DIY Aux-In for Audio 20 Disclaimer: I haven't done this myself, but I thought this might be useful info for SLK owners who did not feel like the Command system is worth the extra $$ and now wonder how the heck they can hook up an MP3 player to their car stereo. On mbslk.de, people are discussing a DIY solution that hijacks the CD audio path of the Audio 20. See here (in German). From what I gather, there needs to be a dummy CD running. One guy says he recorded an audio CD with a flat zero track for this purpose, another says any data CD-R will do. This picture (link updated) was posted for the hardware details. Allegedly, this PCB is accessible from the top of the Audio 20, just by removing the lid, which is held by three screws. Of course, this doesn't give you fancy features like steering wheel control, but it doesn't cost an arm and a leg either. Last edited by Ikarus; 08-07-2007 at 01:58 PM.

06-06-2008	#7 (permalink)
shpritz SLK World Member Join Date: Jul 2007 Posts: 42 Country: Thanks: 4 Thanked 8 Times in 3 Posts	Anyone tried this Mod? Anyone tried this Mod. Seems like an easy cheap solution. Any chance of a english step by step guide on this Mod????

08-06-2007	#2 (permalink)
VitaminT Elite SLK World Member Join Date: Apr 2007 Location: Alabama Vehicle: 2005 SLK55 Posts: 361 Country: Thanks: 0 Thanked 0 Times in 0 Posts	Seems like I saw something either on here or one of the other forums that plugged inline with the audio 20 harness that you could then plug into your ipod. They were holding down the cdc button and it would play the ipod vs cdc. The cdc still worked if you just tap the button. Not sure it works for everyone though.

06-06-2008	#8 (permalink)
shpritz SLK World Member Join Date: Jul 2007 Posts: 42 Country: Thanks: 4 Thanked 8 Times in 3 Posts	Could someone please confirm that the english translation for the German word "masse" in the picture is Common Ground / negative?

06-06-2008	#10 (permalink)
shpritz SLK World Member Join Date: Jul 2007 Posts: 42 Country: Thanks: 4 Thanked 8 Times in 3 Posts	... Do you know if anyone has actually tried it here. Seems a lot easier and a hell of a lot cheaper than spending the dough for a Dension unit or the iTronic. Looks pretty straight forward and easy if you are handy with a soldering iron....

06-06-2008	#11 (permalink)
Ikarus Elite SLK World Member Join Date: Jul 2006 Location: NorCal Vehicle: 2006 SLK 280 w. 6M Other Toys: 2000 New Beetle GLS w. 5M Posts: 596 Country: Thanks: 18 Thanked 40 Times in 20 Posts	Noone here (including myself) as far as I know, but some on mbslk.de have done it. I'm finding that music in the SLK is much less important to me than I thought it would be. When the roof is down, which it is most of the time, the signal-to-noise ratio is worse than with grandpa's short wave radio reception anyway.

06-07-2008	#12 (permalink)
shpritz SLK World Member Join Date: Jul 2007 Posts: 42 Country: Thanks: 4 Thanked 8 Times in 3 Posts	OK. I had some time today and did the DIY Mod discussed above. Very simple and easy to do. Easier than putting in the smarttop. Anyhow it works very well but only works for a few seconds with a blank CD-R and than reads it as a "wrong" CD and switches back to the radio (FM). Does anyone know how I go about burning a flat zero CD or what I would do to get the CD-R to continue spinning without the error message. Can use a soldering iron but not so savy with CD-R's

06-07-2008	#14 (permalink)
UK-C200 Elite SLK World Member Join Date: May 2008 Location: London, UK & Baton Rouge, Louisiana Vehicle: 04 RHD C200K Coupe, 06 LHD SLK-350 Other Toys: Nacra F18 Posts: 580 Country: Thanks: 38 Thanked 124 Times in 78 Posts	Hmmm - well, if you are computer savvy - create a "silent" wave file, say 10 minutes long. y that so that you have 6 copies, and then create an "audio CD" with your burning software. If you want help trying this, drop me a pm and I'll see if I can talk you though it.

06-07-2008	#15 (permalink)
shpritz SLK World Member Join Date: Jul 2007 Posts: 42 Country: Thanks: 4 Thanked 8 Times in 3 Posts	OK got it all done and working. Works fantastic. Here is what I did. Remove the A20 Radio as per instructions elsewhere on the site. 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 hopefully they will upload. For a few bucks you can have a seperate Aux-input on the base A20 head unit without Command.

06-07-2008	#16 (permalink)
shpritz SLK World Member Join Date: Jul 2007 Posts: 42 Country: Thanks: 4 Thanked 8 Times in 3 Posts	Can't get the photos to upload???

06-07-2008	#19 (permalink)
shpritz SLK World Member Join Date: Jul 2007 Posts: 42 Country: Thanks: 4 Thanked 8 Times in 3 Posts	In the mean time I have uploaded the pictures to my Picassa web album and put captions with each photo. http://picasaweb.google.com/jstillwater/A20AUXInputMOD

06-07-2008	#20 (permalink)
shpritz SLK World Member Join Date: Jul 2007 Posts: 42 Country: Thanks: 4 Thanked 8 Times in 3 Posts	Oh yeah. I want to thank Ikarus for pointing me in the right direction and saving me a fortune. Had been looking for a while now and just about pulled the trigger on a Dension Unit which with my A20 without command would essentially do the same thing. Honest guys, if you can solder, the mod takes 5 minutes to do. While you have everything apart you can splice into the cigarette light hot and ground to run your power hide the wires and have a seamless install of your Satellite or MP-3 unit. The Kuda mount looks exactly like it is OEM. http://www.kudausa.com/kuda_mount_an...5-25-254.html# If you have any questions or want any other shots of the mounting unit let me know. Thanks again for all the help.