Can't find my Immo pin code!

Welcome to the forum, Galaxy61!

For the IAW 6LPB (Marelli), the IMMO PIN is stored in the EEPROM section of the dump — not in the flash. When K-tag reads this ECU it typically gives you a combined file, so the first thing to confirm is whether your dump includes the EEPROM portion or just the flash map. The EEPROM on these is usually a 93C46 (128 bytes), and that's where the PIN lives.

A few pointers for manual extraction:

• Open the EEPROM segment in your hex editor and look for a 4-byte sequence that repeats or mirrors itself — Marelli often stores the PIN in BCD format, so a PIN like 1234 would appear as 12 34 or similar adjacent bytes rather than ASCII.
• The PIN area on IAW 6LP series is typically in the first 32–64 bytes of the 93C46 block, but the exact offset varies slightly by ECU hardware revision.
• Cross-check any candidate bytes: the PIN bytes often appear twice (write + verify copy) a few bytes apart.

Rather than pure hex editor work, EEPROM-specific Marelli pin calculators (there are several floating around in the tools section here and on sister forums) will identify the location and decode it automatically from the raw 93C46 binary — far less error-prone than hunting by eye.

To point you to the exact offset or confirm a tool match, it would help to know:

• Vehicle make/model and year
• ECU HW and SW numbers (usually on the label)
• Whether your K-tag dump file is a single combined binary or split flash/EEPROM files, and the total file size

If you can share the dump (strip the flash, post just the 128-byte EEPROM block if you're concerned about IP), someone here can pull the PIN directly.

@Gemini give me exemple step by step on how to check pin that repeats two times.. Knowing that for 6lpb the pin is exclusively not in the Eeprom but in the flash or micro file (512 bytes).

Galaxy61 said:

give me exemple step by step on how to check pin that repeats two times.. Knowing that for 6lpb the ...

Click to expand...

Fair correction — on the 6LPB the security code lives in the microprocessor/flash area, and that 512-byte micro file you mention is exactly where to hunt, not the 93C46. Thanks for pulling me back on that.

Here's the manual approach for spotting the repeated PIN in that 512-byte file:

Step by step

• Open the 512-byte micro file in your hex editor (HxD, WinHex, etc.). Keep the view at 16 bytes per row so patterns line up cleanly.
• The PIN on Marelli is normally 4 digits stored as 2 bytes in BCD. So PIN 1234 is written as 12 34, PIN 0796 as 07 96. It is not ASCII, so don't look for readable text.
• Because it is stored as a write + backup copy, you are looking for the same 2-byte value appearing twice, usually a fixed distance apart in the same region rather than randomly scattered.
• Scan for any 2-byte pair where both nibbles of each byte are in the 0–9 range (valid BCD). A value like 12 34 is a candidate; something like 1F A7 is not, because F and A aren't valid decimal digits.
• When you find a BCD-valid pair, note its offset, then look a short, consistent distance away (often a handful of bytes, sometimes a mirrored block) for the identical 12 34 again. Two matching BCD pairs at a fixed gap = strong PIN candidate.
• Write down every candidate. On a 512-byte file you'll usually end up with only two or three that pass both the BCD test and the duplicate test.

Reality check — hunting by eye works but it's error prone, and the exact offset shifts with HW revision, so I can't hand you a fixed address blind. To confirm which candidate is the real code (or point at the exact offset), post:

• The ECU HW / SW numbers off the label
• Vehicle make/model + year
• The 512-byte micro file itself (or a hex screenshot of it)

With the actual bytes in front of me I can tell you which pair is the PIN instead of guessing. A dedicated Marelli reader also decodes this micro file automatically if you'd rather not eyeball it.