[Forester XT 2015] ECU Replacement

[rodrigoijk]

Hello,

 

I've bought a damaged Forester XT Premium 2015 and I'm starting the recovery process. While I'm waiting for the body parts I'm focusing in putting the engine to run. First I sent the car to an mechanic and he told me that the engine ecu is not responding, because his scanner wasn't able to connect to the vehicle to read any fault codes. After that I sent the vehicle to the Subaru dealership and they confirmed that the ecu is damaged and needs to be replaced.

I think that diagnostic is weird, because the crash didn't affect much the engine or any electronic parts.

 

Does anyone know about something that might be 'blocking' the access to the ecu, maybe due to the crash? Something like the air bag system blocking the engine or something?

 

The dealership is asking me $2000 for a new ECU, while I found an used for around $600. Is it possible to just replace the original ECU by a similar from another car? Is there any kind of locks, keys, passwords or something that might block the communication between the ECUs?

 

Regarding the ECU partnumbers, mine is: 22765AH011, while the used I found is 22765AH010. All the other parts I found in the stores are not equal, but similar partnumbers: 22765AG970, 22765AG973, 22765AH510.

http://parts.subaru.com/

http://www.subarugenuineparts.com/

https://www.subarupartsdepot.com/oem-subaru-parts.html

 

Are all these ECUs the same, but with different 'software versions'? Is it possible to know if they are compatible? All of them are for the same vehicle version: Forester XT Premium 2015.

 

Thanks in advance for any enlightenment!!

 

 

 

 

[rodrigoijk]

Look the number of different versions of the same part.

 

Edited January 12, 2017 by rodrigoijk

[idosubaru]

You're right - ECU failure is very rare, i've never seen it even in totaled Subaru's I've rebuilt.  Yours doesn't even look that bad, I can't imagine it's the ECU. 

 

I would look at the immobilizer - was it triggered in the accident somehow?  

Blown main engine fuse?

Are you using the correct key?

What happens when you insert the key and turn it?  Nothing, is there any power, lights on dash?

 

I would start looking for power - does EVERYTHING in the car have power? 
Does the ECU have power - check whatever wire(s) supply power to the ECU - does it get 12 volts? 

Check ground for continuity. 

Wouldn't surprise me if it's simply not getting voltage or ground. 

 

Check fuse blocks/boxes. 

 

ECU's can not simply be swapped, since 2005 in the US market - they are married to the keys and immobilizer.  

In slightly older models people have gotten a set of keys, immobilizer and the VIN from a donor vehicle and transplanted the entire set up into another vehicle since they're all married together. 

 

Multiple part numbers are completely meaningless - this was true even of ECU's for decades, even back when they were easily plug-and-play interchangeable - they'd all have different part numbers but still swap without any issues.  Can't swap ECU's like that any more due to what i said above but the part number itself is meaningless. 

[rodrigoijk]

How do I check if the immobilizer was triggered with the crash? Isn't the immobilizer just another computer in the vehicle?

 

All the fuses are ok, according to the mechanics. I didn't inspect them by myself. And yes, the keys are correct, they open and lock the doors.

 

This car has a keyless system, so when I push the start button, all the interior lights are turned on and the multimedia is working fine. The lights in the dashboard are displayed and even the mileage.

 

My best option would be to buy that used ECU and ask the Subaru dealership to reprogram it to my car. Do you think they aren't able to do that? I suppose they should have all the keys, passwords, pin codes and everything to replace the original one, but looks like they are refusing just to sell a new one.

[somick]

I would, like Garry suggested, check for ground.  You need to have an electrical diagram.  Try to ground the body of the ECU while testing or check the diagram for ground pin number.

 

Good luck,

Sam

[wtdash]

Time to read the FSM. This is a 2014, but should be close, as the 2014 Forester was all new - in the USA. Brazil? Don't know.

 

http://jdmfsm.info/Auto/Japan/Subaru/Forester/2014/

Edited January 13, 2017 by wtdash

[idosubaru]

That guy in the link above had a dealer reprogram his used ECU to his vehicle.  So presumably it's possible. 

 

On older Subaru's (before they used immobilizers) if the anti-theft system gets triggered you have to insert the key into the ignition and turn the key 3 times from OFF to ON in succession to get the car to start again.  Otherwise it does nothing. 

 

I'm not sure how newer ones with the immobilizers work though - cars101.com probably details that?

 

or someone here surely knows?

[rodrigoijk]

Hello guys, thanks for the help.

 

I bought an used ECU and convinced the Subaru dealer to reprogram it to my vehicle. He tried to do that, but he related the same problem, the used ECU is not responding as well. So now they think there is something else blocking the ECU or preventing it to communicate. :angry:

 

They are 100% sure that it's not the wiring or a power supply problem. They opened a support case to Subaru in Japan and now I have to wait...