GX-204KH radio:
Front:
[INDENT][ATTACH]2359[/ATTACH][/INDENT]
Rear:
[INDENT][ATTACH]2360[/ATTACH][/INDENT]
close-up:
[INDENT][ATTACH]2361[/ATTACH][/INDENT]
Connectors on rear (from left to right, as seen in picture):
1) Fly-lead with Subaru proprietary antenna socket (w/ dual antenna leads)
2) 14-pin socket for power/speaker harness.
Pin-out table
3) 20-pin socket for external CD changer, iPod interface (and in North America, also Sirius/XM satellite radio tuner modules)
4) 8-pin socket for aux input, steering wheel controls, night illumination dimness cancellation.
Pin-out (see section '2007-up Legacy/Liberty/Outback' in post 10 of that thread)
Aux pod exploded view:
[INDENT][ATTACH]2362[/ATTACH][/INDENT]
back of PC board:
[INDENT][ATTACH]2363[/ATTACH][/INDENT]
Pin-out of 6-pin plug on OEM aux harness (plugs into bottom of aux pod)
(in the above picture, pin 1 is the leftmost pad in the row just above the two screws)
1 Right audio (3.5mm plug "ring")
2 Audio Ground (3.5mm plug "sleeve")
3 Left audio (3.5mm plug "tip")
4 Audio Ground (tied to pin 2)
5 Enable switch -- common
6 Enable switch -- normally-open contact
The enable switch is a separate piece "docked" to the tip end of the 3.5mm jack. The tip of the plug pushes the switch. The switch tells the radio to enable the aux button (for details, see link to 8-pin socket pin-out, above).
When no 3.5mm plug is present, the jack itself also shorts the left and right audio signal leads to audio ground (to prevent unwanted noise from getting into the radio). Keep this in mind if you're thinking of wiring a second audio source to the aux input.
