Hey all,

I've been battling with trying to get Immo off working with a spare ecu for a couple of months now. I've read everything I can find on the subject on the forum over that period, trying to get to the source of the issues I'm having, and have come to a point where I am out of ideas, within the constraint of not wanting to open my original ECU.

To give some context of where I am, these are the assumptions I have been working within-

1) It is possible to prep a spare ECU without opening my original ECU. Following Basano's post about preparing a spare Ecu, this seemed like a pretty straight forward proposition.
2) For the most part, MED9.1 ECU's are interchangeable - provided I immo off the spare ecu E2p and copy the spare ecu from addresses 6C00-6FFF to my flash, there should be no issue with Immo - under this assumption I bought an 8P0907115B Ecu, variant 3C0907115S ('07 VW Passat). My car's ECU is an 8J0907115N.
edit: 3) I am using my ECU via OBD, and BDM to read/write to e2p and flash on the spare ECU.

So far I have tried these methods to Immo off

1)Using Technic's tool to immo off the spare ECU e2p - this resulted in a SAFE message, checksum error and fans running
2)Editing the e2p for immo off + spare ecu flash - SAFE MESSAGE, no checksum error
3)Editing the e2p for immo off + my flash with spare ECU 6C00-6FFF - SAFE MESSAGE, no checksum error

edit: Iteration 3 is what I currently have written to the spare ECU.

I also tried, purely to test the immo off function, writing Basano's immo off files to the spare ECU. Still got SAFE message, no checksum error.

I'm starting to think my model may be one of the exceptions to the interchangeable rule, and I need to either a) find a full BDM read with matching SW/HW, or b) concede defeat and just open my ECU.

With all that out of the way, I would really appreciate it if someone could check these files out and see if I am on the right track re: immo off, and provide guidance? I'm not one to give up easily so would really love to get this immo off solution working, if it's possible.

Files as follows -

8J0907115N - OBD read
3C0907115S Read 1.bin - Spare Ecu flash
3C0907115S Read 1.e2p - Spare Ecu e2p
3C0907115S -1 Immo.e2p - Spare Ecu e2p immo off
8J0907115N 6C00-6FFF edit - OBD read with spare ecu 6C00-6FFF

What am I missing here? Thanks for any help, I'm here to learn and want to work this stuff out!

I'm confused, why didn't you read your current ecu and transfer it to clone ecu? You also stated earlier you know where the immo data is. I skimmed over your write up but why didn't you transfer your current data to spare ecu? Heads up winols does some weird stuff in these areas using clone winols. Full version has no problems.