Skoda Octavia 1Z 2.0 FSI – Engine swap BVX → BLX – need help adapting donor ECU / reading PIN

egon.olsen said:

Solved! – BVX → BLX ECU successfully adapted with PINs

Hi Edber,

I just wanted to give you an update and say a huge thank you for your help!

Your information was exactly what I needed. I installed the BLX ECU, entered the PINs you provided and performed the adaptation through VCDS, via Channel 50.

And it worked perfectly!

The engine started normally with the BLX ECU, and the ECU successfully adapted itself to the car. It now shows the vehicle's VIN, IMMO ID and the other vehicle-specific data.

So the BVX → BLX ECU swap is now successfully completed, including immobilizer adaptation.

Your analysis of the EEPROM data and the PINs saved me a lot of time and probably a lot of frustration. I really appreciate your help!

I'd also like to buy you a coffee via PayPal as a small thank-you.
If you're okay with that, please send me a PM with your PayPal details.

Thanks again, Edber — great job and great help!

Best regards
________________________________________
View attachment 8916

Click to expand...

1. Engine swap: BVX → BLX​#

2. Reading both ECU EEPROMs​#

• original BVX ECU EEPROM – read twice and verified
• donor BLX ECU EEPROM – read twice and verified

3. Comparing the EEPROMs​#

4. Help from Edber​#

5. Adapting the BLX ECU with VCDS​#

6. Result​#

• Engine ECU communicating normally
• Vehicle VIN correctly stored in the BLX ECU
• Immobilizer adaptation successful
• No immobilizer fault preventing starting
• ABS/ESP OK
• Gateway OK
• Haldex/4Motion OK
• Airbag OK
• Instrument cluster OK
• Central electrics OK

7. Final result​#

egon.olsen said:

Hi everyone,

I would like to share my experience with my 2007 Skoda Octavia 1Z Scout 2.0 FSI 4x4, as it may be useful for anyone facing a similar engine/ECU swap.

1. Engine swap: BVX → BLX​

My original engine was a 2.0 FSI BVX.

After the original engine developed serious problems, I obtained a BLX donor engine and decided to install it in my Octavia.

The engine swap was carried out from the top, without removing the transmission.

I installed the BLX engine together with the relevant BLX engine wiring and sensors. The BLX intake manifold was also used.

The original BVX ECU remained in the car initially.

The car started and ran with the original ECU, but when I installed the donor BLX ECU, the engine would start and immediately shut down because of the immobilizer.

So the next problem was: How to adapt the donor ECU correctly to my car?

2. Reading both ECU EEPROMs​

I decided to investigate the two ECUs before doing anything further. I removed both ECUs and opened them.

For reading the EEPROM, I used a CH341B programmer.
Before using it, I modified the CH341B to operate at 5 V, following this guide:
https://www.youtube.com/watch?v=hPKckby54uA

I then used IMSProg under Linux to read the EEPROM.
For safety, I did two separate reads of each EEPROM and compared the resulting files to make sure the reads were identical.
I also checked the checksums in IMSProg.

So I ended up with:

• original BVX ECU EEPROM – read twice and verified
• donor BLX ECU EEPROM – read twice and verified

I kept the original dump files untouched as backups.

3. Comparing the EEPROMs​

I compared the two dumps byte by byte.
There were obviously differences between the two ECUs, including vehicle-specific information.
Among other things, I could identify the different VINs and immobilizer IDs:

Original BVX ECU:
VIN: TMBKD61Z278028620
IMMO ID: SKZ7Z0G4049221

Donor BLX ECU:
VIN: TMBKD61Z668057200
IMMO ID: SKZ7Z0E3077195

At this point I posted the EEPROM dumps on the forum and asked for help identifying the relevant immobilizer information and the correct way to adapt the donor ECU.

4. Help from Edber​

A big thank you to Edber, who analyzed the EEPROM data and provided the relevant immobilizer information for both ECUs.
He also suggested trying the proper ECU adaptation procedure rather than immediately modifying the donor ECU.

This turned out to be the right approach.

5. Adapting the BLX ECU with VCDS​

Before doing the adaptation, I put the original BVX ECU back into the car and made a complete VCDS Auto-Scan.
I saved the complete scan and the original ECU information/codings as a backup.

Then I installed the BLX ECU. Using VCDS, I performed the immobilizer adaptation using the PINs provided from the EEPROM analysis and then carried out the adaptation via Channel 50.

After the adaptation, the BLX ECU successfully accepted the vehicle information.

Most importantly: The engine started and continued running normally. Above all, the fan control is now set correctly. The BVX ran at 90°C, and the BLX has an operating temperature of 105°C!

The BLX ECU now shows my vehicle's VIN and the vehicle's immobilizer data instead of the donor vehicle's information.

6. Result​

After the adaptation I took the car on a long test drive.

I then performed another complete VCDS Auto-Scan.
The result was very encouraging:

• Engine ECU communicating normally
• Vehicle VIN correctly stored in the BLX ECU
• Immobilizer adaptation successful
• No immobilizer fault preventing starting
• ABS/ESP OK
• Gateway OK
• Haldex/4Motion OK
• Airbag OK
• Instrument cluster OK
• Central electrics OK

7. Final result​

So the final setup is now:
Octavia 1Z Scout 2.0 FSI 4x4
Original engine: BVX
Replacement engine: BLX
Original ECU: BVX
Replacement ECU: BLX
BLX ECU successfully adapted to the vehicle using VCDS

A huge THANK YOU to Edber for analyzing the EEPROM data and pointing me in the right direction. Without his help, this would have taken considerably longer.

Best regards
________________________________________
View attachment 8928View attachment 8929View attachment 8933View attachment 8932

Click to expand...