Vehicle theft prevention ignition system

摘要

A vehicle ignition system comprises a key cylinder (12) and a key (15) arranged such that the vehicle can be put in a state in which the key is removed from the cylinder leaving the engine running. The system includes a first safety check system which prevents operation to said state unless one or more of a first set of safeguard conditions is met. A timer (34) is arranged to be automatically started to measure a predetermined time delay from removal of the key when the engine is running, and a second safety check system operates when the vehicle is in said state to shut down the engine automatically if one of a second set of safeguard conditions occurs, the second set of safeguard conditions including that the time delay has expired.