You need to provide more details before anyone can help. Please share:
Full ECU part number (you mention 028 906 021 GL — is that the exact number from the ECU label?)
ECU type/brand (e.g., Bosch EDC15, Simos, etc.)
Vehicle model, engine code, and year
What tool did you use to read the EEPROM (e.g., VVDI Prog, Orange5, UPA, TNM, etc.)?
Is this a separate EEPROM chip read, or a full flash read?
Can you upload the file you already have so we can take a look?
With the part number 028 906 021 GL this looks like a VW/Seat/Skoda with a diesel engine (likely 1.9 TDI) running a Bosch EDC15 ECU. If that's the case, the IMMO data is stored in the external EEPROM (usually a 93C86 or 24C02 chip).
To disable IMMO in the EEPROM, the exact content of your EEPROM dump is needed — a generic "ori" file from another ECU won't work because the EEPROM contains data specific to your unit (coding, adaptation values, etc.).
Please upload your EEPROM read and confirm the details above.
If your EEPROM chip is empty (erased/blank), then you need a virgin/clean EEPROM file specifically for 028 906 021 GL to get the ECU running again.
Before anyone can help, please confirm:
What is the Bosch number on the ECU label? (e.g., 0 281 010 xxx)
What is the EEPROM chip type? (e.g., 93C86, 24C02, 95040, etc.)
What vehicle, engine code, and year?
What tool are you using to read/write the EEPROM?
Is the flash (main IC) still intact, or is that also empty?
This is important because:
The EEPROM content must match the flash/software version in the main processor. A mismatched EEPROM will not work.
If the flash is also empty, you'll need both flash + EEPROM files that match each other.
A virgin EEPROM with IMMO off means the ECU will start the engine without any key synchronization — but it must correspond to the correct Bosch HW/SW number.
Please check the full ECU label and share all the numbers you can find on it.
OK so both the flash and the EEPROM are empty — you essentially need a full ECU recovery. Here's what you need to know:
Your ECU details:
VW Part: 028 906 021 GL
Bosch: 0 281 001 655/656
ECU type: Bosch EDC15V
EEPROM: 24C02
Engine: 1.9 TDI AFN 110hp
Vehicle: VW Passat B5
What you need:
Flash file — the main firmware for the flash IC (usually 29F400 or similar). This must match the Bosch number 0 281 001 655 or 656.
EEPROM file — a matching 24C02 dump (256 bytes) for that software version, ideally virgin with IMMO off.
Important:
Flash and EEPROM must match each other. You cannot use a random EEPROM with a different flash version — the ECU will not work.
The Bosch number ending 655 vs 656 matters — check your label carefully and confirm which one it is exactly.
What is the main flash IC chip type? (Check the marking on the chip — e.g., AM29F400, MBM29F400, etc.)
Your options:
Find a donor file set — someone with the same ECU (same Bosch number, same VW part number) who can share a full flash + EEPROM pair. Then раtсh IMMO off in the EEPROM.
Buy a working used ECU with the same part number, read both flash and EEPROM from it, then clone to your unit and disable IMMO.
Send the ECU to a specialist who has a file database for EDC15V — they can reprogram both chips and disable IMMO.
Please confirm the exact Bosch number (655 or 656) and the flash chip type, and I'll try to help further.
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.