[WolfPlayer]

UPDATE

Today I worked with my local Subaru Dealer to do a Key Resynch on the used ECU. Long story short: No worky. Doing a Key Resych on a used ECU allows the used ECU to work on your car. However, the original ECU no longer works. Read on for more information.

Here are some thoughts:
It is my opinion that when a Key Resynch is executed from the Subaru Select Monitor III (SSM3), the immobilizer unit's information gets modified to work with the used ECU. Thus, when you plug your original ECU back in, it will no longer work. Additionally, when you do a Key Resynch, you do not need to plug in the green connectors under the dash. I believe that when executing a Key Resynch, the ECU does not get written to. Rather, just the immobilizer box gets written to. Additionally, this makes a lot of sense if you think about it. All key codes are stored on the immobilizer box. Key Codes are definitely not stored on the ECU. The ECU only needs to handshake with the immobilizer box. The main question for me is - what is needed for this handshake?

The next logical thing (at least to me) is to have the Subaru Dealer do a full SSM3 ECU Reflash exactly like what they would do when installing a new ECU. Why? Well, it is possible that this handshake between the immobilizer and the ECU is done via the VIN. In that case, the VIN gets written to the immobilizer box. One theory is that if the VIN stored on the immobilizer box and on the ECU are different, then you cannot swap ECUs unless the VINs on the ECUs are the same. This might be the case - or might not be. Nobody knows for sure. For the record, when a dealer installs a brand new ECU, they do not need to type in a VIN. Somehow, the VIN gets pulled from another location in the car and gets written to the ECU. I have no idea if a dealer can take a used ECU (that already has a VIN) and set it up as they would do for a new ECU. However, this is the only option left (short of obtaining a new immobilizer box, new key, etc.).

As of right now, I still have a $175 paperweight and I am looking at a $89 service charge to try to get the dealer to setup my VIN on the used ECU.

t

[WolfPlayer]

UPDATE #2

Local Dealer contacted Subaru and was told that they cannot reflash used ECUs. This could mean that I am dead in the water on this one. However, I have to verify. I asked the local dealer if they would be willing to try. If it doesn't work then we're talking about a 10min waste of their time. If it does work, then we can move forward and have something else to try.

As of right now, I still have a $175 paperweight.

t

[halfelite]

The only way is to find a program to copy the whole ecu that contains the good handshake and copy it over to the other ecu. They do it all the times on the evos not sure what immobilizer version they are using though. could be the part that contains the immobilizer handshake is not writable.

[JDM-STI]

You could change a few PIN's and get yourself 2 04 STi ECU's and totally do away with the immobilizer function. Been there and done that.

[Matt Drown]

No new update so far? I've got an ecutek ECU and I was looking to put it aside and work with a stock one on an '06. Having both work is a requirement.

[WolfPlayer]

No Update yet. I was waiting on a return call from the dealer. I will contact them tomorrow.

t

[ciper]

How did this ever turn out? I've recently had a lot of "fun" with the immobilizer on a couple swapped cars. I now have the cars running but also a pile of "unusable" ECM/Immobilizers/keys.