Ghost immobilisers made hidden security mainstream, here is how they actually work

A Ghost immobiliser connects to a vehicle’s CAN bus network and blocks the engine from starting until a personal disarm sequence is entered. That sequence is created using buttons already fitted to the car, such as steering wheel controls or window switches, so there is no separate fob and no visible keypad added to the dashboard.

Because the system does not transmit a radio signal and adds no visible components, it cannot be scanned for or spotted by inspecting the car. That is the whole idea behind the name: a layer of protection that stays invisible until it is needed.

This blocks the two most common modern theft methods head on. Relay attacks and key cloning both work by tricking the car into thinking a valid key is present. A Ghost style immobiliser does not care whether the key is genuine, cloned, or amplified, because it checks for a separate code that has nothing to do with the key at all.

A button sequence has to be entered correctly, in order, every time the car is started. In good conditions that becomes second nature. In a hurry, in the dark, or when a passenger is watching, it is one more thing that can go wrong before the engine will even turn over.

There is also the question of who else needs to know the sequence: a partner, an adult child, anyone who might occasionally need to drive the car. Sharing it means it now lives in more than one person’s memory, and changing it later means retraining everyone who uses it.