
Here is a writeup of how to add an AUX input to your FX, if you do not have the Mobile Entertainment System-DVD player option. This mod uses the "CD / Rear AV" button on the Radio Head Unit.
The first approach uses the unused MES-DVD player harness located under the center storage console. Applies to all '03 and very early '04 models. (My '04 built in Sept, 2003 had the harness, stormace's '04 built in Oct, 2003 did not)
The second approach assumes the MES-DVD player harness is not present, so the same connections are made, but this time it is directly to the back of the radio head-unit. (Most '04 models and later)
Another approach using the SAT-Radio harness can be found here http://www.infinitifx.org/viewtopic.php?t=1787
Credit goes to ak1nza for doing the harness mod approach, and stormace, FoxHawk and Rick64e for doing the headunit mod approach, and ShadyJC for the SAT-Radio method. Many others also contributed...
RadioShack Parts used
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274-249 1/8" (3.5mm) Phone Panel Mount Jack
276-1429 Crimp-type D-Sub (for the pins)
speaker wire
soldering tools
7/32 drill bit (will depend on phone jack)
Optional - PAC Turbo1 audio line driver to boost AUX volume levels Here was the cheapest place I found it - http://www.audiooutfitter.com/store/TURBO1.html
Using the MES-DVD player harness
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Remove rear panel

Open storage bin and pull on back panel. Just grab the sides near the top with your hands and pull. Close the storage bin and the back panel comes off easily.


In mine, the unused wiring harness was taped back, so it was a little harder to find. You can see it in the lower right of the picture.

The wiring harness diagram

First, short out pins 9 and 11 on the harness to activate the REAR AV button.
Connect the headphone jack to the harness. The headphone jack has 3 connections on it, Tip(left), Ring(right) and Sleeve(common)

Pin 1 is Left +. Connect this to the headphone jack tip (Left)
Pin 3 is Right +. Connect this to the headphone jack ring (Right).
Pins 2(Left -) and 4 (Right -). Hook both of these up to the headphone jack common.

Install the headphone jack in the desired location. I installed mine here, but it wasn't the easiest location. It was made of much thicker plastic (probably to support the power socket). Drilling was not the problem, but putting on the locking nut was difficult, since there was not much of the thread exposed. I had to countersink the hole to get it secure, so I would recommend a different location or use a phone jack with a longer mount.


Here is another install location

Posts about this install
http://forums.freshalloy.com/ubbthreads ... r=67413729
http://forums.freshalloy.com/ubbthreads ... r=67620028
Low Audio Volume
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Several people noticed the audio output of AUX input was about half of the volume of the FX CD and FM output. If you are using an IPOD with the Belkin Auto Kit, you will not have this problem, since the Belking kit has a built-in adjustable amplifier. For my mp3 player, I installed a PAC Turbo1 audio line driver to increase the volume output. The PAC Turbo1 also has an adjustable gain.
The PAC amp runs off of 12 volts, so I just used power from the power socket. You can see in the pic, the red wire was pushed into the back of the power socket connector (white wire). For ground, I just attached the black wire to a screw that was screwed into metal.
Wiring changes:
I took a stereo RCA cable and cut it in half. Use one half to connect the DVD harness to the PAC Turbo 1 INPUT side, and the other half to connect the Turbo 1 OUTPUT to the headphone jack.


Posts about this install
phpBB2/viewto ... pac+turbo1
Install with no DVD harness available
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Here are the relevant pics and posts on this. I have not done this install, but it's the same concept, except you are using the connections on the back of the head unit.
Short out pins 38 and 40 on the harness to activate the REAR AV button.
Pin 37 is Left +. Connect this to the headphone jack tip (Left)
Pin 43 is Right +. Connect this to the headphone jack ring (Right).
Pins 39(Left -) and 42 (Right -). Hook both of these up to the headphone jack common.

Posts about this install
http://forums.freshalloy.com/ubbthreads ... r=67769452
http://forums.freshalloy.com/ubbthreads ... r=67809754
edit by particlefx: added the PDF version