My daughter has a 2006 Ford Focus and has been really wanting a plug-in auxiliary input to connect her phone/iPod.  She’s used several different wireless interfaces but has not been happy with them.  So, here’s what I did.

I purchased a PAC AAI-FRD04 Auxiliary Input for about $67.49 (shipping included) from ELEKTEK on eBay.  It plugs directly into the CANBus port on the back of the Ford factory radio (single disc player, NO 6 disc installed) and provides a set of RCA input jacks that can be adapted to about anything.  In this case, I adapted them to a 3.5mm (1/8”) stereo jack that was installed on the dash.

The part that took the longest was purchasing the 3.5mm chassis stereo jack (obtained at Fry’s) and adapting an RCA stereo cable to the jack.  I had several RCA stereo cables, so I simply cut the connectors off one end and soldered the ground, right and left channels to the chassis mount 3.5mm stereo jack.  Here’s what it looks like when installed.  You can see I meticulously soldered and applied heat shrink tubing to all the connections.  The wiring is pretty simple.  The tip of the 1/8” jack is the right channel, the next ring is the left channel, and the sleeve is the common ground for both channels.  See this article on TRS connectors for more details.

To access the radio, you need to remove the trim from around the radio.  To easily accomplish this, remove the junk holder by pushing down on the top to release the clips.  After removing the junk holder, you can reach up inside the exposed hole and push on the trim bezel from behind to begin removing it.  I would suggest using a plastic prying tool to release the other clips.

You can see the top right clip in this photo.  Pry near the clips, not in the middle of the bezel.

Once you have the bezel removed, you should probably disconnect the connector on the back of the lighter socket, as it’s the shortest of the cables and restricts movement of the bezel.  I turned the ignition on and pressed the brake in order to move the shifter out of the way so there was room to move the bezel.

Lighter socket connector.

The radio is held in with four 8 mm screws.  Easy to remove.  Pulls straight out.  No special tools required.

The connector on the back of the radio is also easy to remove.  I disconnected the connector and antenna from the back of the radio so it would come completely out.  On the back of the radio is the Rear Seat Entertainment (RSE) port, AKA CANBus connector.  The AUX device simply plugs into this connector.  It also has another CANBus connector that I assume will accept a CD player, but I’m not sure how it resolves which device to use when you press the AUX button (perhaps it cycles through them).  Perhaps that’s not supported…I don’t know.  It’s down there and available, if it is ever necessary.

Power is always a fun thing to find and connect.  All you need is a little IG-ON power and a ground.  I got it from the radio connector.  I’ve see others get it from the lighter socket.  The black/green wire is ground and the yellow/green wire is ignition-on power.  I used wire taps that worked perfectly.

Of course, drilling the 1/4” hole in the bezel and mounting the stereo jack may freak some people out, but I was very careful to insure clearance on the back of the mounting location.  I used a brad-point drill bit and drilled through the plastic using a fairly high speed to create a clean hole.  I de-burred the hole on the back and mounted my cable/jack assembly and connected it to the FRD04. 

Putting everything back was a snap…literally!  I just stuffed the FRD04 behind the radio, as it is very lightweight and was snugly held in place by the existing wiring.  It ain’t going nowhere.  The cable routed nicely on the right side of the radio towards the bottom.

The final installation.

All fired up and connected.  Pressing the AUX button selects the device.  Works like a hose, and my daughter is ecstatic!

Keywords:

Ford Focus auxiliary input installation.

Pacific Accessory Corporation AAI-FRD04 installation instructions