This information was obtained from this Usenet Post:

http://groups.google.com/groups?hl=en&frame=right&th=874c5b9f385fd337&seekm=NOab888SPAM-0705992311010001%40ip28.ts6.mn.dialup.ottawa.cyberus.ca#link1

/------------------------\
| 1  2  3  .  .  4  5  6 |
|                        | <== pins on socket (header) that plugs
| 7  8  9 10 11 12 13 14 |  into factory radio
|------------------------|

Note:  The above diagram is done from the perspective of looking directly on to the connector pins.  If you are having trouble figuring out which way is which, just use the ground wire, which is always black, as a reference for making sure you are doing the pins correctly.  It is very important to correctly wire up these pins.  If you don't you could cause serious damage to your stereo or entire car.  Please do not attempt this unless you truly know what you are doing.

But I noted that Subaru, most inconveniently, changes the colors that they use for their wiring on a regular basis and do not conform to the wiring standards in anyway.  So, if you have a 1998 Outback you may find the Usenet post useful for determining the proper colors.  The MOST important thing is the pin-out.  Do not worry in particular about the colors.   The specific pins functionality is always the same as far as I know.  I can't imagine them changing that anytime soon either. 


Pin # Color (95 Impreza) Function Sign EIA Color Notes

  1. Green   Illumination  Orange  Not used
2 Red/Orange Line Right Front  + Gray
3 Brown/White Line Left Front  + White
4 Blue/Green Line Right Rear  + Violet
5 White/Red Line  Left Rear  + Green
6 Blue/Yellow Line Memory   Yellow  To Nakamichi Power Line
7 No Connect
8 White/Black Line Right Front  - Gray/Black
9 Green/Black Line Left Front - White/Black
10 Yellow/Red Line 12V   Red  To Nakamichi Acc (+) Line
11 Black (Solid)  Ground   Black
12  Red (Solid)  Right Rear - Violet/Black
13 Red/Green Line  Left Rear - Green/Black
14 Yellow/Green Line Antenna Up/Dn  Blue

I have included the EIA colors for reference.  It is interesting to see how much my 95 Impreza differs from them.  It seems truly odd to me to have my red be a rear right - speaker connector.  This makes it so incredibly easy to misconnect up the lines.  I am shocked that Subaru did this in fact.  But that is another issue…

So, disconnect your old stereo and unscrew it.  Put your new stereo in its place according to the instructions in the manual that come with it.  Then, you need to look at the connector for your new stereo and connect the proper pins according to its diagram to your Subaru stereo harness.  I used bullet plugs and soldered them because my Nakamichi used bullet plugs for all the connections.

Wiring Harnesses vs Cutting Off the Original Connector:  There are two camps of people, those who choose to use wiring harnesses and those who believe in cutting off their original connectors.  I did not choose to use a wiring harness, though many nice ones are available for many car models as can easily be seen by a simple search on the internet.  If you choose to use one, it might make your install much easier.  In addition, it can greatly simplify the later removal of the stereo.  I, choose not to use one because I am very confident in my skills, and I believe that they are detrimental to the signal quality.  In fact, I know that they are if compared with an experienced person soldering with high quality solder.  So, I chose to go with the latter route.  The choice is yours.  The soldering route does take considerably longer and requires you to work in the close/cramped space of your car.  I am not concerned with the difficulties of later removing it as I am quite experienced in doing things like this.  The choice is yours, either route is worth thinking about depending on your abilities/experience/if you are leasing,etc.