DIY: Aux input to OEM radio/CD

[anothernord]

Disclaimer: Doing this modification carries the risk of destroying or damaging your radio: I am not responsible for any damage you cause as a result of this DIY. Carry on at your own risk.

This modification requires that you have the OEM radio from the 96-99.

2000-2004 folks; see the end of this post for your pinouts.

Basically what this hack does is use a 3.5mm headphone cable that you solder to the board of the radio where the CD connects to it. Then a burned CD of "silent" tracks is played, and you can connect whatever device to the cable, and your music plays in CD quality in the car.

--Things you will need:
Tools:
-Soldering iron (pen is best)
-Phillips screwdriver
-Wire strippers
-Dremel
-Small flat head screwdriver

Materials:
-Shrink tubing
-A couple inches of random wire
-Solder (duh)
-3.5mm stereo cable
-Blank CD
-Silent sound clip: (Save As): http://www.instructables.com/files/orig ... 056PBO.mp3

Irreplaceable things:
~1.5 hours


I. Start by removing your radio/cd deck. I won't go into detail here because its pretty self explanatory.

NOTE: If you don't have a CD player in your car, you can still do this mod, but you have to wire in a switch to trick the radio into thinking there is a CD player present. See the end of this post. (credit to Soul Shinobi for this find)

II. Once you have your radio/cd out and in a clean work area, remove the 8 screws that hold the CD deck and radio together on the sides.




III. Remove the two smaller screws from the back of the radio unit.



IV. Using the small flathead screwdriver pry off the top plate.



V. Now take a look at the cluster of pins. After cutting, stripping, and separating the wires from your 3.5mm cable, solder them as shown onto the board. I used a small piece of wire to extend the ground wire of the cable to make it easier to solder, as the connections do get pretty close to each other.

Be sure that wires or solder bridges don't cause a short.

Red goes to "RCH"
White goes to "LCH"
The bare ground wire goes to "S.GND"




VI. Get out your dremel and notch the case of the radio to allow the cable to easily fit through.




VII. Re-assemble the entire unit, and screw the bracket back on to hold the CD and radio together.

VIII. Return to your car, and plug all the connections back in, being sure to re-screw the grounding wire.



IX. Now you need to burn a CD of "silent" tracks. A clip can be found here: (Save As) http://www.instructables.com/files/orig ... 056PBO.mp3

X. Put in your silent CD, press play, connect an audio device to the 3.5mm jack, and see if it works! If it doesn't you either soldered the wrong pins, or possibly shorted out the radio. Also, test your silent CD to make sure it didn't burn improperly.

If it works, jam out to your favorite song, then put your dash back together, and run the cable where ever is most convenient.



If you don't have a CD player: (96-99 only)

Credit to Soul Shinobi for this part, including the pictures.

This situation is basically the same as above, but you must add a switch that connects "B+" and "CD PLAY" together to switch the head unit in and out of aux-in mode.

Black Top: S.GND (Audio Ground)
Red Top: RCH (Audio Right Channel)
Black Left: B+ (Battery Voltage)
Black Right: CD PLAY
White Bottom: LCH (Audio Left Channel)



For you Third-Gen guys:

The mod is mostly the same, but with a different pin configuration.

Credit to beastman for this find and these pictures.




The red wire from your stereo cable goes to pin "a"
The white wire goes to pin "c"
The ground wires go to pin "b"




Let me know if you have questions, or if you find an error in this DIY.
-Nord

[DLC]

Awesome.

[anothernord]

Yep, I can confirm that the sound quality is waay better than my old FM transmitter. Too bad all the backlight bulbs my radio are burned out.

Also, this same process should work for most Subaru radios that have a separate CD player. The pinouts might be different but they should be labeled.

[StatGSR]

does it still play cds?

[anothernord]

Yep, works fine with all other CDs.

[Soul Shinobi]

Might it be possible to make this work if you don't have the CD player? I assume you'd have to trick the main unit into thinking a CD is being played, perhaps by bridging some connections with a switch in between?

[anothernord]

Might it be possible to make this work if you don't have the CD player? I assume you'd have to trick the main unit into thinking a CD is being played, perhaps by bridging some connections with a switch in between?

Yeah, I think it is possible. When you press play on the CD, it sends the signal to the radio telling it to look for a feed coming from the CD port.

Edit: I would try putting a switch between the "CDPLAY" and ground pins.

[Soul Shinobi]

Alright I've got my radio out and an auxiliary 3.5mm cable; it was a pain to solder with my crappy iron and poor lighting. Now it's a matter of figuring out how to set the radio to CD Play mode, which is necessary for the radio to accept the auxiliary input. After some trial and error by bridging pins with a paperclip, I found that: to enable CD Play mode without a CD player, the "CD PLAY" pin has to be connected to the "B+" pin (wire a switch in between if you ever want to listen to the radio again).

I'll finish wiring my switch in and take pictures. Tested, works. I swear my radio reception is worse though, even though I'm sure everything's plugged in right including the antenna. Maybe I damaged the antenna cable pulling it to get a little more workable room reinstalling it.

Reposted for reference:

Disclaimer: Doing this modification carries the risk of destroying or damaging your radio: I am not responsible for any damage you cause as a result of this DIY. Carry on at your own risk.

...

V. Now take a look at the cluster of pins. After cutting, stripping, and separating the wires from your 3.5mm cable, solder them as shown onto the board. I used a small piece of wire to extend the ground wire of the cable to make it easier to solder, as the connections do get pretty close to each other.

Be sure that wires or solder bridges don't cause a short.

Red goes to "RCH"
White goes to "LCH"
The bare ground wire goes to "S.GND"
EDIT: This may be incorrect, see later post here.

Mine:




Black Top: S.GND (Audio Ground)
Red Top: RCH (Audio Right Channel)
Black Left: B+ (Battery Voltage)
Black Right: CD PLAY
White Bottom: LCH (Audio Left Channel)
EDIT: This may be incorrect, see later post here.




Installed. Switch moves left for on, right for off, because there wasn't enough clearance at the bottom after I made the hole. The aux cable didn't require a hole, there was enough of a gap below and to the side of the ash tray.




From the driver's point of view.

[anothernord]

NICE!!!! Its like a double DIY.

I am totally ditching my CD player and doing that. The CD is a pain because it makes a little gap in the music when it goes back to the beginning of the CD. Plus its extra space.

[Soul Shinobi]

So glad I could help! Listened to it for the first time to and from work today, great clarity. With this setup you can hear just about no static if nothing's plugged into the aux jack.

I do have to say, max value isn't too impressive compared to the stereo in my '92 Legacy. In fact I listened to it on max the whole time, which was just about perfect, but what if I wanted more? My mp3 player is at the medium volume setting (I could turn that up, sacrificing battery life), but the stock stereo from my '92 could blow the doors off with the mp3 player set to medium. Both head units are labeled 80W, would the difference have to be in the speakers? Makes me wonder if I am getting a small short where I soldered CD PLAY as it appears in the picture; or would that cause a more obvious issue?

EDIT: You could still do this and keep your CD player, in case your friend shows up for the road trip with a binder of CDs. I wonder if it's possible for this to mess something up if the CD player is plugged in though...

[anothernord]

I think that's normal; my iPod touch needs to be turned to almost max, with the volume at about 3/4 on the car to get it loud enough for certain types of metalcore. But for Eagles, Tom Petty, and Def Leppard, its fine at half and half.

[Soul Shinobi]

Maybe I'll try to swap a speaker from my '92.

[Huffer]

Great DIY guys.

[Soul Shinobi]

Thanks.

I've got some tweeters that I had picked up at a junk yard, I might install them today. On my "CD PLAY" switch I wired it in with small wire nuts (no very legit outside of home wiring, I know ) but I may solder in a two pin connector taken from a third tweeter I had picked up (more-or-less by accident).

[Soul Shinobi]

MIND BLOWING UPDATE

It turns out that for the 3.5mm TRS plugs we're wiring up we were completely wrong about the red wire being the right channel and white being left. I'll edit my above post to refer to this one.

I found this out because I installed a different plug and wire (my original had an internal break causing the music to cut intermittently), this one had ground as yellow instead of black, so I decided to test it to be sure.

1. Sleeve: usually ground
2. Ring: Right-hand channel for stereo signals, negative phase for balanced mono signals, power supply for power-requiring mono signal sources
3. Tip: Left-hand channel for stereo signals, positive phase for balanced mono signals, signal line for unbalanced mono signals
4. Insulating rings

To confirm which wire did what, I set my voltmeter to continuity (you can use resistance if you don't have continuity as an option) then touched one lead to the tip and touched the other to the wires to find the left channel wire. Repeat for the ring and sleeve sections of the connector. Both my old and new connector had red as left channel and white as right channel.

I wired the new one up as such, then tested the finished product with some left/right test mp3s on my player, which I found here. I've just found a better test mp3 that has both left and right tests in one file, here (direct download, right click > "save (target) as...").

[chris_2.5gt]

Hey guys I know this is an older diy, but I was curious... if don't have the cd player would it not be easier to just plug the wires into the plug in the back of the radio instead of opening the radio and soldering? I know you would need to figure out which pin was for the left and right but that is just trial and error in my opinion... the switch on the other hand may be a littler harder to figure out.

[Soul Shinobi]

You could do that, but it'd be hard without having the actual connector to wire to. Also you'll have to open up the radio to test for continuity, so you know which pins are for what.

[anothernord]

Right, you could just stick wires in along side the plugs, but you'd have to open the case anyway to see what pins to use, and at that point, you might as well just solder the three wires and be done. Its much cleaner that way.

[chris_2.5gt]

The only reason I was asking is because my soldering gun is not that precise...pretty large tip

[anothernord]

The only reason I was asking is because my soldering gun is not that precise...pretty large tip

I used a big tip for mine; it was pretty tricky, but it was easy to plop a blob of solder when it only takes a second to melt it rather than minutes with those stupid cold heat irons. Never buy one of those pieces of garbage.

[chris_2.5gt]

That's what I have!! haha I hate it. The first time you use it you think this is great...then after a while your trying to find the point on the tip that actually will heat up

[Soul Shinobi]

This is the one I have, it's the only one with a fine tip I could find around here (there are better ones on the internet but they cost more). I got it at Home Depot for $17, I'd recommend it, you'll wonder how the hell you did anything without a fine tipped soldering iron. Just don't forget to tin the tip when using and storing it to keep it conductive.

Link!

[beastman]

I have a 2001 legacy GT wagon. Stock head unit with tape, and stock CD player. My circuit board looks nothing like yours, but I think I may have found the right place to solder. Where the CD harness plugs in, there is a row of pins. The furthest right pins are labeled a and b. The wires going into the harness that match up are (a)red and (b)black. There is also a pin labeled "g" with a grey wire in the respective spot in the harness (ground maybe?). Should I be able to assume that these would be the pins I'm looking for to connect the aux cable?

Edit: MY INITIAL GUESS WAS WRONG. The correct pin assignment is as follows:

"a" is for right channel (red wire)
"b" is for the signal ground (my ground wire was yellow)
"c" is for left channel (white wire)


Here's a pic:

[Soul Shinobi]

Really can't just to conclusions based on that... I don't know if the service manual would have details on the internals, likely not. You might have to start to guess and test.

[anothernord]

Be very careful not to fry the deck. I tried doing this to a 01 RS deck, and I fried it because the pinout I had was incorrect.

[beastman]

if i dont connect the ground to "g", can i still test to see if a and b work? or should i just go for it?

if this doesnt work im buying a new head unit anyway, so im not terribly concerned about the stock one.

[beastman]

Found the pin out diagram!



So, I need to connect the red aux wire to "A". Black aux wire to "C", and ground to "B" correct? Glad I didn't guess...

[beastman]

WORKS LIKE A CHARM

Thanks for the write up. I really shoulda taken pictures of the finished product since it was on a different radio, but I was too nervous and had to try it out. The diagram was right on, and the pins in the photo I took are the correct ones. Here are the tools I used:



The solder was $17 at Lowes. It's a "hobby" solder so it was nice and small, battery operated, and perfect for this job. I already had the aux cable, so overall it was less than $20 total. I spent about 1 hour searching through multiple forums, and the whole job probably took me 1.5 hours.
PSYCHED!!!

[anothernord]

Awesome!!! This thread keeps getting better and better!

I wonder if the 02 WRX's plug looks like this... I will have to take a look. We might have an aux-in revolution for Subaru owners on our hands.

Edit: I updated the OP with the new information that Soul Shinobi and beastman have come up with, with credit given to them.

[beastman]

I do believe the connection on the stock WRX radio is the same. I actually found the pin assignment on nasioc. About halfway down the linked page you will see the back of the stock HU and the connector is the same, not sure about inside but I can only guess it's very similar.

http://forums.nasioc.com/forums/showthr ... 652&page=2

I should also note: the pins I tapped into were on the BOTTOM of my radio, not the top like the earlier models.