Write Up: Alpine Cd Changer + Aux To Volvo Sc Hu's

[crazykn]

This write up is now complete. Can a Mod or someone pin this please (don't let my hard work go to waste).

First off, let me give you a bit of background on this project. I have a Alpine CHM-601 CD Changer in my car and before I built my own electronic switcher between it and my Blitzsafe AUX in, I used to run my CD Changer via a Alpine RF transmitter, which didn't give satisfactory sound. I didn't want to get rid of my Blitzsafe, because I use it to listen to my iPod and Sirius radio. So I knew that if I wanted good quality sound out of my CD Changer I would have to build my own device. So I started a little project. I built this as a 'technical excerise', so that I can help out fellow members who would like to have a Alpine M-Bus CD Changer in their car without having to purchase a adapter if they were willing to produce their own. So I started out building one adapter. Turns out because of the proprietary jack on the Volvo HU, that adapter didn't quite fit. So I was going to trash it, be decided to let a fellow member have it (AkitaWagon) for free. The night before I was to meet up with him, I was playing with the adapter and then something struck me. I suddenly found the solution, or at least a close enough solution to modify the shell of a standard 8 pin miniDIN to fit the Volvo. So before I met up with him, I tried in my car and it worked and staying in there well enough that it could pass for a quality product I sell. But I decided not to charge him for it (although I ended taking a trade for his Alpine HU), because if I wasn't thinking about it so deeply, I might have not have found this simple little modification, and this adapter might not have existed and thus, everyone would still be ripped off buying expensive brand-name adapters.

So, you have a Alpine CD changer and you would like a AUX in for your stock Volvo SC-xxx HU... or if you want a AUX in and would like to get the CD Changer as well... well this is your solution! At the time of writing, i'm not aware of such a product that would adapt the a Alpine M-BUS CD Changer to the Volvo SC-xxx HU AND a switched AUX in. After so many posts about tapping the CD Changer cables, I decided to make a adapter so that you don't have to buy a adapter that would cost $30 or more and have to hack it up so that you can have a AUX in. Alternatively if you would just like the CD Changer adapter, you can ignore the other half of this write up.

Lets get started:

First you need to know how to solder! If you don't, then click this link: http://www.tangentsoft.net/elec/movies/

Select the first and second movie and watch the tutorial. Great vids and great site, I learned a lot of DIY electronics there.

Obviously you need a soldering iron, and some of the following tools:

A good pair of wire strippers:

Needle nosed pliers, wire cutter and a helping hands tool (It'll save you a major headache when soldering):

If you are planning to make a CD Changer to Volvo HU adapter only without the AUX in, then you won't need the following:

A power drill.

___________________________________________

Materials:

I'm assuming that you have some 20-22 guage stranded wire of different colors... colors always help.

You will need about a little more than a foot of cat5 cable, radioshack sells it in bulk, so it'll be like a dollar or so. You may also use a old cat5 cable as well (as long as it still works). You will need to order the following parts:

www.mouser.com is the best place to source these parts.

PART NO. Description QTY $$$

806-KMDAX-8P 8-Pin MiniDIN 2 $1.41 each

16HR638 8-Pin DIN connector 1 $3.97 each

Now you must be wondering why i'm saying to order TWO 8-pin MiniDIN connectors. If you read on, you will realize why quickly. So for now do as i say or else . Here is a pic of those parts and the cat 5 cable I found laying around:

Since there is connector on it, feel free to cut off its head :

Alright, if you plan to do the AUX in as well, order these parts:

PART NO. Description QTY $$$

108-0010 DPDT Mini toggle switch 1 $2.74 each

161-3402 3.5mm Jack. 1 #0.43 each

You will also need some telephone wire, a 4 conductor cable approx 3 feet, again radioshack or your local hardware store. This will be useful to carry the audio to the switch and back... rather than running 4 extra wires around. I got 50 feet from a 99 cents store...

You will also need some posi-lock connectors... they might not be cheap, but they save a lot of hassle during installation and modification to the adapter afterwards. Highly recommended for this type of application:

(Side joke: I was installing a HU for a female friend of mine once and I was using posi lock connectors, because some prick cut off her stock radio harness and stole the radio... but yeah I was telling her how much I love these connectors... all you have to do is insert, and start screwing... and I told her: "hey lets posi-lock..." ).

You will need a blank switch cover from your car to the switch (and maybe the input jack for the AUX in) on.

[crazykn]

______________________________

Now that we have our materials together. Lets get familiar with the connectors and what pin does what:

MiniDIN Connector, This one will goto the HU.

DIN connector, this is where you would plug the Alpine CD Changer into.

You may want to print it out, as a reference when you solder.

If you really are the technical type, this is pretty much all you need just use the cat5 cable and start matching pin to pin and add the battery wire for the bigger DIN connector.

But since most of you out there aren't , keep reading... plus I haven't taught you my little secret of how to make a standard 8-pin MiniDIN connector fit the proprietary Volvo connector.

Ok, first step, strip the cat 5 cable, and sort out the wires by color, keep them grouped by their color... ie, orange and orange/white strip as one group such as below:

Now before you begin to solder... decide what wire should do what and write it down (this is your color key here):

So, lets get ready to solder! Now take apart one of the connectors and note how its assembled....

[crazykn]

Ok, now take the holder of the pins out and start to insert the wires in:

^^ Those are the Data wires.

Now solder them:

TIP: Solder from the bottom up (bottom row up), it makes soldering much easier.

Because the wires are sometimes exposed because the heat of the soldering iron can melt the insulation of the individual wires of the cat5 cable, you can wrap the connectors after soldering them:

Next row, the ignition wire power and power ground connectors. One of the connectors on this row has no connection, so you can ignore it:

TIP: As you are doing this, make sure that there are no solder bridges, where the solder is touching a pin that it shouldn't be.

Next row: Audio, and you can continue to wrap them in electrical tape if you feel more comfortable doing so.

[crazykn]

Ok, I get to reveal a secret here...

Now so far most people who have tried to make a standard 8 pin miniDIN connector fit inside the Volvo Proprietary connector have realized it doesn't work because of two indentation on the lower half of the shell:

Here is my secret: buy TWO connectors, and use the round and not indented shell of the spare connector. Put them together and Volia, you have a fully round connector! Minus a slight pin offset, its the best fit possible from this connector, and when I tested this out, it worked well and held well in my car!

Now lets assemble the shell.

You see this lower indented part, just toss it:

Now take the round portion of the metal shell out of the spare connector and if you put them together you get this nice round shell:

If you try to assemble the whole shell with the pins and all, it won't work, because the holderthat holds the pins is keyed, so you won't put the wrong shell on the wrong side. Well no worries, just take one of the round metal shells and cut off the the little thing in the middle (this will be the bottom shell) as shown in the pics:

[crazykn]

Now remember that I told you that one pin has no connection?

So there is extra wire left over (and if you noticed in my key, its the blue/white strip wire). This is our shell or body ground... technically its not necessary, but its a shield for the audio and data signals. so take that wire out... wrap up the rest of the connector with the electrical tape. You must do this, so that the pins don't touch the shell and short out.

Now just leave that wire dangling... so that when you assemble the shell, it will make contact with the metal shell. After all thats what a shell and body ground is!

Now go ahead and assemble the shell:

Don't be afraid that the connector has a gap between the shells...it will still fit and believe it or not it will also the connector to the Volvo plug, because it will naturally push outward from the center... don't worry it won't push out.

Continue with the plastic portion:

Cut off the other end of the cat5 cable if your using a old cable.

Now before you put on the boot... DON'T push it all the way, because the connector in the HU is a bit deep... so you want the plug to have a little space. Push it just to this amount in this picture and not anymore to be on the safe side:

Now give yourself a hand for finishing the hardest part of this write up .

Lets move on. Now lets look at the 8 pin (bigger) DIN. I want you to make a minor modification so that the Alpine CD Changer cable will be easier to insert. For some strange reason, the design of the female pins on this connector makes it tough at first to push in the alpine male connector. But if you put a strengh into, you will get it to mate. The connector are matching, so there will be no damage to the connector as long as you are careful.

Now look at the 8 Pin connector: Notice at the at top or 12 o'clock position there is this flat metal thingy in that little dent on the plastic part of the connector, this thing is purely optional, and needs to be out of the way, otherwise it'll make shoving the Alpine connector a pain in the rear. Don't try to pry it out, because it might tear the metal inside, making it even hard to insert. Just take a needle nose plier to FLATTEN it.

[crazykn]

Here is the flattened metal contact. That contact is the body/shell ground, but since its already tied to the body of the connector, its not needed anymore:

Now go on the back of the connector and the top thin lug, just bend it (carefully) upward and out of the way. This lug is the shell/body ground connector:

Here is another view.

[crazykn]

Lets solder again! Get those pin diagrams ready again!

Ok, get a wire (preferably yellow, because its the battery (constant 12V+) wire and yellow is the standard for the battery) and solder it to the battery lug:

You may want to put some electrical tape around this connector, because its constantly getting power and you don't want it shorting to any of the pins around it:

Okay now go ahead and solder everything else (just match it to the pins), EXCEPT the LEFT and RIGHT AUDIO wires (solder the AUDIO GROUND though). This is just a matching the pins and wires from the miniDIN connector to this connector and remember the shell/body wire/lug.

OK, we are now at a cross-road. From this point you can either make a CD Changer ONLY adapter or a AUX in and CD Changer adapter. Decide and decide well.

If you are going to make a CD Changer adapter ONLY, then go ahead and solder the AUDIO LEFT AND RIGHT wires to their corresponding lugs on the DIN connector and wrap the connector up in electrical tape:

^^^ Wrap the the all the connectors except the shell/body lug first as pictured. This isolates that plug from shorting other lugs/pins out. Then wrap the whole thing up and you are done. To install, just plug in the Alpine CD Changer cable to the DIN end and the miniDIN end to the HU. T-Tap the yellow wire into a constant 12V+ (battery) source. There is one in the radio harness... just do a search and you should find out which wire it is..

If you decided that you will do the AUX in switch, then lets continue. This will actually get a little more complex, but the rewards will be waiting for you if you finish it.

[crazykn]

Go ahead and pull back the LEFT and RIGHT Audio wires (blue and green on my adapter), we do a little more soldering.

Go ahead and solder in a wire (I used green) into the audio ground of the DIN connector. (there should now be two wires on that lug). Also solder a wire to the LEFT audio on the connector and another to the RIGHT audio on the connector.

If you haven't figured out yet, the three wires you just soldered are going to be the wires that gets the audio from the CD Changer. These wires will lead to the switch so that you can switch between CD Changer or AUX in audio.

Now go ahead and wrap it up (the connector) with electrical tape just like how you would do it for the CD Changer adapter only method.

Ok, now get ur posi-locks out !

Now lets get back to those LEFT and RIGHT audio wires from the cable... (not the ones from the connector), strip a little off and posi-lock it (the instructions are on the packaging. Just unscrew, put the wire in and screw tight, and the wire is locked it). It should look something like this (I did one wire in the pic, but do both ok?):

Ok, i'm sure by now you probably figured out what the wires you just posi-locked do... they are the wires that go to the HU (or the MiniDIN). This wire will carry the audio to the HU. So when we install the switch, the switch will select the audio going to these wires.

Now go ahead and posi-lock the other tee wires... the ones that get the audio from the CD Changer or the wires connected to the DIN connector:

[crazykn]

Lets take a break from solder... but don't turn off that iron , we'll still be using it.

Ok, did you take a blank switch cover from the car yet? If not go out there and go pry it out.

I don't care if you're still in your underwear, go do it... otherwise where are you going to mount the switch?

Well lets take that blank cover and put a hole into it (I didn't actually remove this cover... I got it from CJ (300+T5R), courtesy of him, my blanks can stay where they are!). So get your power drill out...

Now using some telephone wire, because its less messy than individual wires, cut approx 3ft of it:

Now also cut 3ft of wire (I prefer green, this will be the audio ground).

Ok, lets make sure you got everything...

Before you bust out your drill bits, decide whats best spot on the blank for the switch? Do you plan to put the AUX in jack on the cover itself? Do you prefer to hide the AUX in jack?

Well... if you do decide to put the jack up front, then drill two holes. Actually in hindsight, I shouldn't have drilled the hole in the center... i must've breathed in too much soldering fumes ... I just wasn't thinking straight...

You might notice before you drill that the blank cover underside has a little plastic post thingy near the center... go ahead and use your wire cutters and get rid of it:

Now lets prep the little connector jack: Solder some short wires to it... just as shown.

^^^

Here is the key to the jack... from top to bottom:

Top connector: LEFT AUDIO

Middle connector: RIGHT AUDIO

Bottom and facing 90 degrees down: AUDIO GROUND

DON'T GIVE UP! We're almost to the end!

[crazykn]

Now go ahead and strip a little off the 3 ft (green) wire. Solder to the jack's ground connector:

Next, solder the short little wires, to the switch. Solder it to one end of the switch, not the middle... the middle lugs are for the wires that will feed the HU. Note which wire are LEFT and RIGHT, because the side you solder it to will make one side of the switch LEFT or RIGHT.

Now lets use that telephone cord. One pair of wires will bring the audio from the CD Changer to the Switch... and the other pair will bring audio back to the HU. So lets decide what wires will do what:

Signal from CD Changer:

Yellow: Right audio from CD Changer

Black: Left audio from CD Changer

Signal to HU

Red: Right audio to the HU

Green: Left audio to the HU

You don't have to use my color scheme, but write it down so you won't forget!

So solder the red and green wires to the switch's center lugs. Keep in mind which is the LEFT and RIGHT signals. Then solder the yellow and black wires to the other end of the switch:

Again, you may use electrical tape to prevent shorting of the pins... its up to you.

Once soldered. Go ahead and mount the switch and jack (if you want the jack up front, otherwise leave it dangling in the back) using the hardware that it came with:

Strip off the other end of the 3ft telephone cord and the 3ft audio ground wire.

Take the adapter and switch/jack to your car. T-Tap the yellow wire (battery) to the radio harness or another constant 12V+ source.

Now this is why you I told you to use posi-locks. Go ahead and fish the wires from the switch to the behind the radio. Obviously remove the radio (BE SURE YOU KNOW YOUR RADIO CODE BEFORE REMOVAL!), before fishing the wires over.

Go ahead and connect up the wires by function. It should look like this (I didn't actually install this in my car):

Here is a little diagram of what I did to connect them:

ADAPTER END SWITCH (REMOTE) END

- - - - - CD CHANGER AUDIO SIGNAL - - - - -

Big Green wire Big Green wire

Red Yellow wire

Black Black wire

- - - - - TO HEADUNIT SIGNAL - - - - -

Blue Green wire

Little Green wire Red Wire

Once you wired it up. Test out the system. Enjoy!

by the way: I will be soon selling the adapter I made. If I hadn't already bought a Blitzsafe adapter and built my own electronic switching box, I would keep this cable. I'll keep everyone updated!

[connorb850]

Wow, pretty extensive writeup you did!

Looks great Kelvin :tup:

[AkitaWagon]

Wow, pretty extensive writeup you did!

Looks great Kelvin

Great writeup Kelvin! It's nice to have them with lots of clear details and pictures.

BTW, OEM HU to MBus cable #1 (or is it the prototype model?) is working fine without any issues. Front dash is taken apart so I haven't been using it for the past couple of weeks though.

I'm thinking about getting your cable (maybe two; with aux). It's a good excuse for me to finally get an iPod, especially since my connections can get it with at a good discount.

Do you have a source for the flat, circular, toggle switches with the LED indicators? I tend to accidently snag and break things that 'stick out' like the lever versions and would like something more flush with the panel.

[crazykn]

There are many many switches out there I could easily obtain. I did the write up the toggle one, because I had it laying around.

As long as the switch is a DPDT type (Double Pole Double Throw) it will work. Plus you can mount this switch anywhere, it doesn't have to be on a blank. If for some reason that you find a switch you like, but its not a DPDT type, we would have to go with electronic (relay) switching. This is actually easier for me to construct, but it would obviously cost a little more (i.e. $10 extra). Plus with electronic switching, you don't need as many wires going to the switch and you can place the "switch box" anywhere in the car.

The electronic switchbox is what I currently use. The box is on top of my CD Changer in my 850 and the remote control switch is with my dash switches.

If I were to sell this type of product I would mostly likely sell a electronic version for the AUX in CD Changer. Not the one in the write-up. The one in the write up is a tad bit difficult, even for me to produce in a reasonable amount of time. To construct a electronic version would be a lot easier and quite possibly even cheaper for me to produce, with the same good quality stuff I produce. I'm estimating I can put out such a product for around $45.

Now I want to make it clear that I cannot make a AUX in ONLY adapter. Although I have reverse engineered the blitzsafe AUX-in (and yes I do own one), I cannot reproduce its Alpine M-Bus signals. Two reasons, I don't own a intercooler reader and two, I don't want to get sued by Blitzsafe for copying their 'code'.

So this adapter is clearly for people who have a Alpine CD Changer or is willing to install one. The CD changer will provide the emulation for the HU to accept the AUX and CD Changer audio.

And yes I currently am willing produce Alpine to Volvo CD Changer ONLY cables. In the near future I might consider selling electronic switch boxes for the AUX and CD Changer audio.

[crazykn]

BUMP!

[nbran]

will this work if i dont have a cd changer and just want to get an aux input???