24-pin Aux Retention
In Subaru models listed at the top of this page, the factory HU has a 24-pin socket on the rear for its stereo aux input. A factory harness connects from the back of the HU to the back of the 3.5mm aux jack (in the armrest center console). That harness has proprietary plugs at both ends. The harness handles the stereo aux jack only, not the USB socket (if present).
The white 24-pin connector on my aux adapter fits the end of the factory aux harness that is (or was) plugged into the back of your factory-installed HU.
I'm currently offering this harness in either of two options for the aux connection:
If you have the OEM Kenwood navigation HU (with maps on DVD) and you order this harness, let me know — the aux leads are on slightly different pins than on non-nav models.
Retain h/k Amp Trigger Signal
In 2010–2012 Legacy/Liberty and Outback models with the factory harman/kardon amplifier and speaker system, the OEM HU provides a remote turn-on signal via a pin on the 24-pin aux harness. If you plan to retain your h/k amp, you'll need to supply a +12V trigger signal to this pin on the car's 24-pin aux harness.
I can build my 24-pin aux harness with corresponding wire.
Cars with the HU models covered by this page do not have any other signals on the factory 24-pin harness such as reverse gear, parking brake, etc.
Retain OEM Rectangular-shaped Subwoofer
Subaru offered a rectangular-shaped under seat subwoofer for some models whose HUs have the 24-pin aux harness. On some, the HU supplies a line-level signal for the sub. That is in contrast to Subaru's previous under-seat subs, which simply tapped the front speaker outputs from the HU's main power/speaker harness.
If your car has the sub which requires the line level signal (and if you wish to retain that sub), I can build my 24-pin aux harness with an additional male RCA plug and 6" (~150 mm) long amp remote turn-on lead. Price: Add $13 to any of the above configurations of the 24-pin aux retention harness (to add the subwoofer RCA plug and amp trigger lead).
If you think you need to include this RCA plug on my aux harness, please e-mail me so that I can confirm your OEM subwoofer is the type which requires it.
This RCA plug is not needed for cars with the OEM harman/kardon amplifier and speaker system!