Immobiliser Issues

[norbs]

Farkenell !!! Mate hats off to you for persisting. If it were me I'd probably have torched it

[jaydece]

Brainy.....you've heard my comments and statements via this crazy journey....top effort from yourself and mechanic dad.....patience, persistence and perseverance.....hats off to both of you...

[alexeiwoody]

Good effort mate! Replacing wiring loom is only for the brave

(I personally like the torching idea)

[ndlibgt]

Kudos to ya B.

[imania]

Great work Brian, commendable persistence. Now hopefully back to enjoying the car!

[dr20t]

Brian

Highly commend you for the efforts and for sharing alot of the info which has been sporadically been mentioned on here before for future reference

Glad to see your issue sorted

I will add a few things to this post for future reference

The first and most important thing people need to realize is that the gen4 liberty was the first Subaru vehicle to incorporate canbus into the electrical system. This integration means a very complex connection between many many many sensors, modules, switches, controllers and wires.

Below is a far from a comprehensive list of things linked to the canbus which could trip up and cause an issue like the one you saw in your car:

Key
Biu
Ecu
Ignition barrell
Gauge Cluster
Tcu for auto
Abs module
Fuel pump controller
Fuel pump itself and the fuel sender unit
Ac control module
Various engine/ gearbox / centre diff sensors
Transmission neutral safety switch or inhibitor switch for auto
Various wheel / abs / speed sensors
Lateral g sensors in various parts of the vehicle (found one on underside of fuel tank)
Brake pedal switch and clutch switch in manual
Accelerator pedal position sensor for dbw
Light dimmer switch which is also connected to the interior light circuit from memory


With respect to starting the car without the cluster in - this will definitely not work. Tried it personally. It will also not work with a different cluster plugged in. Infact won't even get the shift lock mechanism to move if another cluster or no cluster is plugged in

There are literally a handful of people I have found in Sydney other than Subaru who can recode biu / cluster. And they charge big bucks to do it as they know its a scarce service.

One thing I'm experimenting with at the moment is transplanting the responder cluster chip into another cluster to see if that will work. Problem with that as Brian has pointed out, is the boards on the clusters themselves are physically different. Plugs are the same, but the wires are in different positions for various things between pre and post facelift GT for example. Pins 19 and 20 are reversed, and the post facelift in missing two wire inputs that are on the prefacelift (presumably related to cruise control stalk separate on the steerin wheel in preface as opposed to on the steering wheel controls for post facelft, and a wire trigger for dual avcs to high speed canbus input)

Transposing the entire wiring loom as Brian has done is an absolutely massive massive job which I don't really think many people get an appreciation for until they see how involved it is. And this in itself is an admirable expedition.

Thank you again for raising this and hopefully all your gremlins are sorted

Mick

[jslayz]

My hat is off to you sir.
Seriously solid effort!!

Thanks for sharing the info.

J

[brainy]

Thanks guys for the comments and great info DR20T!

As Mick said, if the biu, cluster, keys and ecu aren't coded together, then it won't work. Swapping just a cluster is pointless as it will reject the key and throw on the immobiliser light. Thankfully, I had access to a subaru dealer who were sick of seeing my car in the end, but they were nice enough to reprogram the cluster, ecu, biu and keys to match without charge. One thing they won't do, and i have no idea why is reprogram old keys to match. Having said that, there's a few documents online that tell you how to do this but having two new keys, i haven't bothered trying.
This issue was considered unsolvable by the guys at subaru and it even came to the point they offered me a trade in solution and they would just send the car off to the auctions as buyer beware. They were quite supportive, but sadly at the same time, they were a bit rough when going through what they did (exposed wires, broken clips on panels, etc).

The loom i got was from an 07 post face lift and having a my08, I was really surprised seeing how in just 6 months difference in build date, how much it had changed in sections.
The CANBUS system relies on twisted pair wires for communication in sections and i sadly now know that the twists are a certain distance and you can't have it non twisted any further than 8cm from the end of the plug. But Mick is absolutely right, the whole CANBUS system was created to reduce the number of wires in the car, and it really does talk to every system and sensor.

It feels like that more bolts and clips went back in the car when putting it all back together and my greatest fear was hearing rattles from panels. I'm glad to report that the previous rattles i used to have are now gone and i'm relieved.

Thanks again guys, and lets hope no one needs to ask me questions about wiring diagrams.

Back to tyre shopping!

Brian

[vicious_fishes]

Hey guys, bumping this thread for info.

I'm in the middle of an engine swap into an impreza and having a bit of a headache. I'm trying to reuse the factory ecu/canbus system to avoid shelling out for an aftermarket ecu and I've come across this thread.

I read in the OP that you apparently need the ecu, bcm, key, immobiliser and cluster all to match. I've got the engine in and started doing the wiring only to discover that i didn't get the immobiliser with the donor cars harness, or the cluster.

However, we've managed to reuse the impreza body harness to get the engine to kick over, and the throttle body will also move. What we don't have is spark or pulse. What I'm basically wondering is (and not to rag on the OP) if the information about needing the cluster and what happens if you don't have it or the right key definitely is accurate. It doesn't seem to me that the throttle blade would move if the ecu was indeed waiting for the immobiliser to tell it to let the car run, but that might not actually be the case.

Can anyone shed some light on what will/won't happen if X component is missing? I don't want to second guess you guys or anything but if there's a way we can get it running without the cluster then that will save me a LOT of money over buying an M600 or something that doesn't need the canbus system to work.

I am swapping an EZ30R/H6 if that makes any difference.

[bigBADbenny]

Afaik, once you have your complete set of immobiliser parts and its all installed, you'll need to trailer the car to a dealer to get it all coded.
This is the process if, eg you have replaced your ECU due to eg water damage.
Maybe Sharpie: ex STi foreman could confirm that info...
Iirc, some ECU mods may disable the immobiliser function, eg ECULabs... Or as you mentioned an aftermarket ECU...

Other than that, I'd be googling eg Impreza H6 swap builds to see how it's been tackled previously.