Reasons for car immobilizer repairs include faulty sensors, BSI Units, actuators, engine ECU or immobilizer ECU. Additionally, immobilizers can malfunction because the manufacturer-provided key fob loses coding or its transducer chip. Damage to the car's wiring may also warrant immobilizer repairs.
Several symptoms can indicate a problem with a vehicle's immobilizer. If the security alarm is not working and the doors do not lock with the key fob, the immobilizer may be malfunctioning. While the vehicle may start, it often stops immediately. Finally, the vehicle may not start at all, and a dashboard light indicating problems with the immobilizer points directly to the problem.
The immobilizer system is made up of a radio frequency identification key, radio frequency identification reader, and coding housed in the ECU. When working correctly, the key sends signals to the reader when inserted in the ignition, which then travels to the ECU, which determines if the key has the correct code to start the vehicle. Each part must be coded identically in order for the vehicle to start. Immobilizer system repairs are completed by first determining the malfunctioning component and then recoding the system so it functions with the replacement component.
Immobilizer systems help lower incidents of vehicle theft, as they require similarly coded keys to start the vehicle and are not as easy to hotwire. While vehicle theft does still occur, it is usually the result of directly towing the vehicle or stealing the keys in order to drive it away.