My security light is blinking and my car wont start. I don't have my owners manual to fix the security problem, what do i do?

U can try a security reset of the system which is called the VATS Passkey anti-theft system, if this doesn't work u are stuck,the car must go to the dealer to have the system tested to see what is causing the problem, the most common is the key code sensor has failed or is giving an erratic signal to the VATS module, if u have a 2nd spare key try that as well. You don't say year, the rest procedure only works for 1999 and up Passkey systems.

PASSKEY LOCKOUT RESET ALL GM CARS 1999 AND UP
1) Put the key in the ignition and turn to the "ON" position. Leave it that way for 10 minutes. After 10 minutes turn the key and take it out. Repeat this process (2) more times (3 times, 30 minutes total) This should reset the PASSKEY system to recognize your key.