From what I can see there, on that plug, there is a white wire, which has a blue trace (or line, if you want basic lingo) on it, and a red wire with a white trace on it. Sorry, I really should have explained that one, my bad.
From what I can see in the manual, theres not a lot of 3 pin connectors in that location. One of which is the ABS 'G' sensor. Somewhat crucial to the operation of the ABS and perhaps the airbag systems. Another one is supposed to be black, and thats the turn and hazard module.
But I doubt the manual goes in depth at this level to bridging connectors - ie a plug to join 2 looms together to make removal easier. They get covered under each individual system.
At this stage I cant find anything in the gen 3 liberty/legacy manual to say what it might be. Did this part of the loom get shipped off to AM Auto? You may be looking at a forester part of the loom, which I dont have any info on.
Best bet for quick fix is to hook a battery up and see if a fault code comes up. The A/C system has its own diagnostics separate from the main ECU, I'll have a look later tonight to see what the process is for that and will let you know. I'm sorry I cant be of more help, this sort of thing is painful to try and fault find.
Edit - Champion! - that will help him majorly. Download that and check out the wiring system part - there is a section there thats called 'Harness components location' that is what I've been refering too - make sure you look at the specific sections for RHD/Wagon/no of cylinders for your original car though - otherwise you'll be chasing your tail.
Cheers,
Ben
MY00 Red RX, a nice daily that was sold off once the B4 became reliable...
MY02 Blue B4, aka 'The Project' - v8 JDM STi engine package and assorted other 'goodies' - Sold, then bought back for parts. Stripped and crushed.
MY03 Blue RX, the newer old daily, pretty well more B4 than RX now... In the process of being converted to the track toy... Watch this space!
MY02 Silver Wagon, H6 conversion, full blue/black leather and almost full black interior to go with it. In process of being stripped and sold off.
MY03 White/Silver H6 Outback, donor car for silver waghoon. Scrapped.
MY97 Silver RX, acquired to become track car, but plans changed. Scrapped.
MY13 BRG, current daily, very nice to drive, small mods to make it even nicer again.