[bobbyd]

I bought a 2nd hand ECU with the intention of getting it retuned for extra performance- this can be done at a local dynotune place.  I was hoping to keep the original ECU with standard factory programming untouched and have the ability to swap this back when the vehicle was sold/serviced etc.

When i fitted the 2nd hand ECU the engine wouldn't fire up- cranked over ok but wont run. I rang the wreckers only to find out that the ECU also has the immobiliser in it and this needs reprogramming to match the car.  Not sure i want to take it the the local dealer and try to explain why i have a 2nd ECU when the car is still under warranty.

I know some other cars (some commodores/falcons i believe) can be self reprogrammed by putting another ECU in it and leaving the ignition on for a few minutes or more -this matches ECU to car.  I'm not sure if the I30 will allow the same or if there are any other methods to mate the ECu to car? 

[Dazzler]

Good luck bobbyd.. tricky question that one (hope someone can help) 

[2i30s]

try getting the keyfob for the car that ecu came from. it wont work on your doors,but it should DE immobilise the ecu. 

No matter what you do, you can not reprogram each of the ECU to match the keys you have.  If one is reprogrammed with your keys, the other ECU will then not match the keys you have.

You will need two sets of key fobs, or, if you have two key fobs, get one programmed to match one ECU and the other to match the other ECU.  It's not the key that is reprogrammed, but the security chip in the key fob.  This includes the security chip in any of the keys that didn't include the remote (supplied before tow remotes became standard in Aus).

How do I knnow this - well, from experience.  When we got the second remote key, it had to be programmed, along with the existing remote key fob.  As we didn't have the key without the remote in the car, it was not reprogrammed and would not start the car.

Then, we had a security chip fail.  The secirity chip was replaced (not the remote, just the chip in it), and all three keys were reprogrammed.  Now all keys work, including the non-remote.

Sorry to add further problems to your bright idea.

Bob

[bobbyd]

thanks guys

[bobbyd]

Found out the ECU doesn't actually pair up with the keys- putting a foreign ecu in you can still open and close the car with the original key, i'm in the process of finding out how to get the ecu authorised for the car at the local dealer.

[Surferdude]

Found out the ECU doesn't actually pair up with the keys- putting a foreign ecu in you can still open and close the car with the original key, i'm in the process of finding out how to get the ecu authorised for the car at the local dealer.

I think you'll find they're two different mechanisms.
The button you push is for the remote central locking.
The transponder is embedded in the head of the key and doesn't react to any buttons.

[2i30s]

yep,the keyfob is talking to your doors but not the immobiliser,so to speak.    if you lock your doors with the key using the doorlock it is locked but not immobilised. using the button on the key to lock it will immobilise and lock it. 

[marvy]

I bought a 2nd hand ECU with the intention of getting it retuned for extra performance- this can be done at a local dynotune place.  I was hoping to keep the original ECU with standard factory programming untouched and have the ability to swap this back when the vehicle was sold/serviced etc.

When i fitted the 2nd hand ECU the engine wouldn't fire up- cranked over ok but wont run. I rang the wreckers only to find out that the ECU also has the immobiliser in it and this needs reprogramming to match the car.  Not sure i want to take it the the local dealer and try to explain why i have a 2nd ECU when the car is still under warranty.

Yea that's not gonna work. To start the car you need 3 things to match. You need the ECU, you need the matching Key, and you *also* need the matching electronics in the ignition switch. The car is designed so that crooks can't just swap in a new ECU and take off with your car. They would also need to swap out the electronics in the steering.

As a side note, the ECU also has the VIN number of the vehicle programmed into it. This means that the service centre ( or the police ) can tell if the ECU has been swapped out.

As other have mentioned also, reprogramming the keys has a procedure as well that's designed to make it difficult for crooks to take advantage of. All keys must be present during reprogramming, you can't just add a new key. If you did, the other would stop working.

I had the same idea to try tweaking with the ECU at one stage. Another thing that I noticed was there there was a huge number of ECU part numbers. I never worked out why this was but it seemed to be very difficult to get a second hand ECU and get it to match the car one exactly. Perhaps it's something to do with the matching ignition unit, I don't know.

Let me know how you go

[bobbyd]

I gave up, the other ecu could be programmed to swap into my car, but then putting the original ecu back would require reprogramming also.  Sounded like and expensive process with too many questions asked by the dealer if you know what i mean