As soon as the vehicle tracking system suspects your vehicle has been stolen it will report it to the 24 hour monitoring service and you will be informed. If the vehicle hasn’t been stolen you can tell this to the monitoring system and it will go back to monitoring. however if the vehicle has been stolen then it will be reported to the police and the engine of the car will be cut out (turned off) as soon as the car becomes stationery.
Once the vehicle tracking system has cut off the engine it cannot be restarted by the thief. So your car can no longer be driven, minimising damage to it and making it very likely that you will receive it back in good condition.