It does not sound like a security problem. Must of the time the motor starts then the computer turn it off. You are not turning over the motor like a low or bad battery. Ken
Your vehicle is equipped with the Passlock® theft-deterrent system.
Passlock® is a passive theft-deterrent system. Passlock® enables fuel if the ignition lock cylinder is turned with a valid key. If a correct key is not used or the ignition lock cylinder is tampered with, fuel is disabled.
During normal operation, the security light will go off approximately three seconds after the key is turned to the RUN ignition position following an engine start.
If the engine stalls and the security light flashes, wait until the light stops flashing before trying to restart the engine. Remember to release the key from START as soon as the engine starts.
If the engine is running and the security light comes on, you will be able to restart the engine if you turn the engine off. However, your Passlock system is not working properly and must be serviced by your retailer. Your vehicle is not protected by Passlock at this time. You may also want to check the fuses,