Bosch ME7.5 Immo Off: VW, Audi, Seat and Skoda 1.8T and 2.0 Petrol ECU Guide

The Bosch ME7.5 (and its close relatives ME7.5.10, ME7.5.20 and ME7.5.30) is the engine ECU of the VAG 1.8T, 2.0 8v and some 1.6 petrol engines in the Golf IV, Bora, Passat B5, Audi A3 8L, A4 B5/B6, TT, Seat Leon 1M, Toledo, Skoda Octavia I and Superb I. It is also the favourite ECU for engine swaps into kit cars and older chassis, which makes ME7.5 immo off a permanent best-seller among our immo off files.

Immo 2 or Immo 3?

• Immo 2 (roughly 1998–2001): the immobilizer box sits in the instrument cluster; the ECU stores a code. A used ECU needs a login (SKC) adaptation or immo off.
• Immo 3 (2001 onward): cluster and ECU share the 14-digit immobilizer ID and a 7-digit login. Matching a used ECU requires the SKC of the cluster; without it, immo off or a virgin file is the only way.

Symptom in both cases: the engine starts and stalls after about one second, immo lamp flashing, fault 17978 / P1570 Engine start blocked by immobilizer.

Immo off or virgin?

Immo off is the right answer for swaps and for cars whose cluster is dead or replaced by an aftermarket dash. Virgin (immobilizer reset) is the cleaner answer for a road car with a working cluster: after writing, an adaptation with VCDS using the cluster SKC pairs the ECU normally and the immobilizer stays active for insurance and inspection purposes.

Reading and writing the ME7.5

1. OBD (K-line): Galletto 1260, MPPS, KESS V2 and BDM100-era tools read the full 512 kB / 1 MB flash. Keep the battery on a charger — the ME7.5 is unforgiving of voltage drops mid-write.
2. Bench: KTAG or Flex on the bench read the flash and the 95040/95080 EEPROM. The EEPROM is where the immo data lives, so bench reads give the full picture.
3. Note the Bosch number 0 261 20x xxx and the VAG part number 06A906032xx / 8D0907551x; the software version must match the file.

Write the file with the same tool. Checksums are corrected inside the file; if a tool insists on recalculating, allow it — the result is the same.

Common pitfalls

• ME7.5 files are not interchangeable between wideband and narrowband lambda versions or between manual and automatic gearbox variants.
• A cluster replaced without matching Immo 3 IDs will keep the lamp flashing even after immo off; that is cosmetic.
• After immo off, the engine can be started by anyone with a key blank — fit a hidden cut-off if the car goes back on the road.

Where to find your file

See the ME7.5 collection for immo off, virgin and original files, or browse by brand: VW, Audi, Seat, Skoda. Unlisted software numbers are handled through the file request form.