So I hacked in an audio jack to hook up my 1st gen ipod. Just slightly modified instructions found here. I got a 1/8 stereo jack from RadioShack (P/N 274-0246 for those interested) and a small push-button on/off switch. Picture is attached. A bit dusty around there 'cause I took the pic before I cleaned everything up.

 

As for my question, I noticed that there is no power in the lighter outlet. All the wires seem to be intact. I am pretty sure that there used to be power there before, and I didn't do anything to it while wiring the stereo connections. Here's a pic of the wires, for what that's worth:

Does that look about right? Is there a fuse I could check for?

Subarus generaly require the ignition switch to be in the "ON" position for there to be power at the lighter. If there is not any power when the switch in in the ON position check for a blown fuse.

There is a fuse for cig lighter and some other functions on the same wiring, so you may want to check to see if that fuse is good.

 

However, I had a situation where fuse was good, but lighter socket had no power. What causes this, is that there is a fuse link built into the lighter socket, that can blow without blowing the fuse at the fuse block. This turned out to be my problem. To repair, I disassembled the lighter socket, and bent the metal clips together to by-pass around the bad fuse link to restore electrical power.

 

IMO, the lighter socket design is not good, and a real PITA to repair.