KermaTDI Immobilizer Delete for VW and Audi (Bosch ECU)

Immobilizer Delete for VW and Audi (Bosch ECU)

Please note: some Siemens and Continental/SIMOS ECUs are not supported. Contact us for availability if your ECU is not Bosch, before ordering.

KermaTDI offers an immobilizer defeat service for VW and Audi (VAG) vehicles. This requires sending your ECU to our service center (a different address than our Colorado shop, sent to you in your order confirmation email). Most ECUs run $159, though some may require an extra charge. Cloning service is also available on most models.

What is an immobilizer?

Most VW and Audi cars since about model year 2000 include a factory anti-theft system called an immobilizer, or "immo" for short. When working properly, it allows the engine to run only when the correct key starts the car. A malfunctioning immobilizer makes the car undriveable: the engine starts, then shuts off within a second or two, with the "car and key" symbol lit on the dash.

An immobilizer delete reprograms the ECU to ignore the immobilizer input entirely. The car then runs independent of the immobilizer, even if the immobilizer hardware itself is defective.

How it actually works:

1. Shortly after the engine starts, the ECU asks the immobilizer module (located in the instrument cluster) for an "ok" to keep running.
2. The instrument cluster checks for the transponder chip in your ignition key, through an antenna in the steering column.
3. If the key's signal is detected, the cluster tells the ECU to keep running.
4. If not, the cluster tells the ECU to shut off, lights the "car and key" symbol, and stores a fault code.

With the delete installed, the ECU no longer asks the instrument cluster anything, so the car starts and stays running regardless of the immobilizer's condition.

Other reasons owners request this service:

• Lost or additional keys that trigger the immobilizer, avoiding an expensive or inconvenient dealer reprogram
• Installing an aftermarket remote start, which the stock immobilizer normally blocks
• Replacing a failed ECU with a less expensive used unit. We can duplicate your existing ECU's data to the replacement if needed

Important: not all no-start problems are immobilizer related. If the car doesn't start and run at all, it's not the immobilizer. If it runs for a few minutes then stalls while driving, or runs rough and misses, it's not the immobilizer either, and a delete won't fix a dead battery, empty tank, or unrelated mechanical issue.

Audi A4 Quattro owners (2003-2007): if your ECU part number starts with 8E0, deleting the immo will get the car running again, but the horn will honk and side markers will flash for 4 minutes afterward due to a factory alarm quirk unique to these cars. We can't override that factory alarm behavior with an immo delete, but we can retrieve your pin code for a nominal charge if you need to adapt a new ECU or keys. Contact us for details.

After purchase, you'll receive shipping instructions and the service center address by email.

FAQ

How can I tell if I have an immobilizer problem?
If your car starts and runs but shuts off immediately with the "car and key" symbol lit on the dash, you likely have a faulty immobilizer. Look for fault code P1570 or 17978 ("Engine start blocked by immobilizer") when scanned with an OBD reader.

My car won't start at all. Is that the immobilizer?
No. If the car doesn't start and run at all, it's not immobilizer related. The same is true if it runs then stalls after a few minutes, or runs rough and misses. Those point to other mechanical or electrical issues, and an immo delete won't resolve them.

Will deleting the immobilizer stop the dashboard light from flashing?
Not always. The immo delete separates the ECU from the immobilizer's input, so the engine runs regardless. But if the flashing is caused by a broken antenna or transponder chip, the instrument cluster may keep flashing since that function lives in the cluster, not the ECU. At that point, the light is cosmetic only. Some owners simply remove the dash bulb.

Does this work on all VW and Audi ECUs?
Most Bosch ECUs are supported. Some Siemens and Continental/SIMOS ECUs are not. Contact us before ordering if you're not sure which ECU your car uses.

How does shipping work for this service?
After you order, we email you the service center address (different from our Colorado shop) along with instructions. You remove your ECU, ship it in, and we return it once the delete is complete. Keep your own shipping records for tracking.