The solution is to buy a new unit.
Use our structured guide to diagnose, reset, and repair your car’s immobilizer system hardware and software issues.
Can it stop engine from starting
Immobilizer problems can look like a dead battery, a bad starter, or a key fob issue, but the root cause is often a communication failure between the key, antenna, and vehicle security module.
If your bmw won't start but still has electrical power, this guide covers 12 troubleshooting tips from battery issues to faulty alternators to get your car started again.
If the key is not the correct one, this system blocks different actions to prevent the car from starting.
Immobilizer problems can be frustrating, but with the right knowledge and tools, you can fix the issue and get back on the road
Remember to diagnose the problem correctly, follow the step.
With the bmw 335i’s direct‑injection turbo engine, fuel pressure and sensor data are especially critical
The list below covers the most likely causes when your bmw 335i cranks but fails.