What does it mean if the security light stays on after trying to start the vehicle?

If the engine does not start and the security light stays on, there is a problem with the immobilizer system. Turn the ignition off and try again, or try using another transmitter or placing the transmitter in the transmitter pocket located in the center console. If the ignition mode will not change with another transmitter, the vehicle needs service; if it does change modes, the first transmitter may be faulty and should be replaced and programmed at a dealership. (Page 30)