04 Forester XT ECU for 06 WRX

[turbomacncheese]

I'm going to tie up my two other posts to culminate here. For reference:
https://thefactoryfiveforum.com/show...-(not-antenna)
https://thefactoryfiveforum.com/show...Us-sti-fxt-wrx

If you want the short version to catch up, my immobilizer (2006 WRX) is NFG. I've called my local Subaru dealership and asked for help, but I guess they're pretty busy and haven't gotten back to me yet. If they say they can swap me in an immobilizer and hook me up with some keys, I'm going to seriously consider towing it there because I've just got too....many....projects.

In the meantime, I'm working on a backup plan...finding an 04 FXT and matching up the pins where they belong. If I get frustrated with this exercise AND the dealership takes a pass on helping me (or just wants more $$ than I'm willing to pay) I'll go with a standalone. Either way, ONE of these last two options is certainly going to be in my future, because I'm really not cool with an immobilizer that I have no control over killing my car. Truth be told, I'd probably just get a standalone right now if it didn't seem like an even BIGGER project to right (and didn't cost $1500...but I'm pretty sure I'll end up spending that eventually).

So, my goal for this thread is finish a mapping from the one to the other, and ask for some help along the way. I've already gone through the WRX ECU and I'm looking things up right now for the Forester.

First question...
Cruise control set indicator light. This is from B135pin3 on the WRX, and I can only find this for the FXT in Combination meter, METER-03, B16. Turbo comes from ECM, but I can't find a connector or pin.
cruise set indicator light.PNG
In this context, "B15" seems to be pin 15 on connector i10 (tot he combo meter). I can't find the destination to the ECU in combination meter, cruise control, or engine electrical. Any tips or ideas?

[Bob_n_Cincy]

Turbo,
I used an 2004 fxt donor. Here is my schematic.

https://1drv.ms/b/s!AgduxxAs3q-xgaRk...ESpTw?e=hlCSyc

After reviewing we should spend some time on the phone together.
Bob 513-eight five one - three seven four eight

[turbomacncheese]

Next question:
The accelerator pedal position sensor seems to be different. I found some references to the 04 vs 06, and it looks like the earlier has a larger plug (I don't care except that means it IS different). The wire diagram looks similar, but the wire order (and two colors) has changed. Does anyone know about this specifically? Should I be working on the idea that the blue wire and yellow wire (for example) carry the same function for both pedals (hence the pin change)?

pedal position sensor.PNG

[Bob_n_Cincy]

Turbo, I do know the 04FXT is same engine and Harness as the 06 STI. Only the FXT comes with a smaller turbo.
What harness are you using?

[turbomacncheese]

06wrx harness. I'm pretty sure the wire color indicates the function here (for the accelerator pedal), but without a pedal to inspect and not knowing what happens after the pin on the ecu, I'm basically blind.

[Ajzride]

Turbo, I do know the 04FXT is same engine and Harness as the 06 STI. Only the FXT comes with a smaller turbo.
What harness are you using?

06WRX = 07STI

It’s why I couldn’t use the 04 Forrester ECU and I had to buy a new 06ECU/Immobilizer combo.

[turbomacncheese]

What about the 06WRX can't the 04FXT run?

[driveslikejehu]

I haven't really followed all this, but I noticed "06 STI." That's what I have, so if I can check a wire or connection that might help, let me know.

[turbomacncheese]

Thanks. I think there was some confusion earlier on what I'm working with. My donor was an 06 WRX, and the immobilizer failed. I was told that the 04 FXT was the most recent 2.5 turbo with single avcs and similar sensors, so I'm attempting to chart what it will take to buy one of those, cut and crimp a bunch of wires, and result in a running engine. The fxt ecu is typically about 300-450 bucks from what i see, the 06 wrx is closer to 500-600, but i'd also need a matching immobilizer and key/cylinder. I've seen those combos for closer to $1000, but still with the potential for the immobilizer to leave me stranded.

Last night I debated selling the car vs a standalone ecu.

[Ajzride]

Thanks. I think there was some confusion earlier on what I'm working with. My donor was an 06 WRX, and the immobilizer failed. I was told that the 04 FXT was the most recent 2.5 turbo with single avcs and similar sensors, so I'm attempting to chart what it will take to buy one of those, cut and crimp a bunch of wires, and result in a running engine. The fxt ecu is typically about 300-450 bucks from what i see, the 06 wrx is closer to 500-600, but i'd also need a matching immobilizer and key/cylinder. I've seen those combos for closer to $1000, but still with the potential for the immobilizer to leave me stranded.

Last night I debated selling the car vs a standalone ecu.

I have a working 2006 ECU with immobilizer and I've finally decided I'm going stand-alone. So if you want my setup, I'm open to selling it. I've sent several people my spreadsheet where I researched the 04FXT to 06 swap, were you one of them? If not I can send it to you.

[turbomacncheese]

I was. It was my starting point for this thread. I'll send you a pm about the ecu.