2011 Toyota Matrix Owners Manual - Page 89

1-6. Theft deterrent system Engine immobilizer system The vehicle's keys have built-in transponder chips that prevent the engine from starting if the key has not been previously registered in the vehicle's on-board computer. Never leave the keys inside the vehicle when you leave the vehicle. The indicator light flashes after the key has been removed from the engine switch to indicate that the system is operating. The indicator light stops flashing after the registered key has been inserted into the engine switch to indicate that the system has been canceled.