Vehicle Theft System Light Explained

Theft / Security Light

The security system on todays cars and trucks prevents the vehicle from being stolen. There are many variations of the system going back to the early 1990's.

This warning could be on when the engine is running, indicating a fault has been detected in the system. If left un repaired, there is a good possibility that the car will eventually not start.

There are several different possibilities for the cause of the warning, depending on the make / model / year of the vehicle. Anything from a bad ignition cylinder wire, to a bad cylinder to a dad Body Control Module (BCM).

After market (non-factory) alarm and remote start systems can cause havoc with the factory theft system, causing this warning light, or a no start.




1997 Olds regency security light blinks and car wont start.
 ANSWER: Possibly the common problem of the wires are broke on the back side of the Passkey ignition key cylinder, so the theft system cannot read the key.

i have a 1999 Olds Alero and it runs fine i can park it and walk in to the store and come back out to start it and it wont start the security light is on we can some times let it sit for a little while and it might start.
 Many articles on this website for this problem. Just do a search.

My 97 pontiac Bonneville security light is on and the car wont crank how can i get my car to crank
 Possibly the common problem of the wires are broke on the back side of the Passkey ignition key cylinder, so the theft system cannot read the key.

I started up my car and the security light was on, drove a few miles then parked and turned car off. Started it back up and the light was off. I do have an issue with one of my car locks, its stuck and wont lock. What may the Security light mean ??
 The theft system saw a problem, and you are lucky the car started that next time. Usually they don't. Sounds like a problem with a bad Passlock Sensor Cylinder. A scan of the codes would be needed to confirm this.

I have an 2002 Olds Aurora 3.5 V6 and have been having trouble with the security system. It seems to happen after a heavy rain or running it through the car wash. The dashboard lights flash, the DIC screen flashes service stability system, security system fault, air bag problem. The traction control goes to the off position and won't go back on, the engine temp gauge and the gas tank gauge indicator goes to zero, etc. All kinds of crazy stuff. Yesterday, the security light came on. I parked the car and shut the engine off. When I came back out from a store I visited the car would not start. I called Triple A and they came out quickly but at the time of their arrival, the car started. They ran a diagnostic on it and everything else was fine, battery etc. However, when I drove it the security system went crazy again but the car still ran. Any comments or suggestions about what is going on with this situation?
 You have many more problems with your car than just the security system. This is just one of the problems. You have an electrical issue that is effecting many different systems. With what you describe, i would suspect a loose connection or bad ground getting wet, or a bad ignition switch.

i have a 2000 chevy malibu alarm started going off lights flashing horn honking car still starts theft system light does not say on but the little red light above radio flashes and head lights flash and horn honks can not figure out how to make the stupid peice of crap stop doing that i do not have remote or stock radio help me PLEASE
 Possible bad body control module. This control the alarm and lights, among other things.

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