When I bought my 99 Camaro the security light was on. The car has an aftermarket radio, speakers and amp. (I assumed this is why the security light is on). Whenever I lock the car the horn beeps like normal, then about eight seconds later it honks twice like the alarm is going off. When the car is locked at my house it will do this a couple times throughout the night(randomly), It only does it when the car is locked. Any ideas?

 

Mine will do this too, but not every time i lock it just sometimes, even if i relock it, it still will do it. I always have to manually lock the doors then the next time i go somewhere and lock it i use the key fob and it works. Not sure what the reason is but you could try that.

 

When I manually lock the doors as soon as I close the door after about 8 seconds it will alarm off for two honks just as if I locked it with the remote

 

the reason is the wire connections of radio...i had the same issue with my previous 96 RS i had a kenwood on then the security was on i tried evey single wire it just didnt go off! and sometimes the car just wont start i drove the car with the security light for a year lol no problems then...try to figure the radio connections out...

 

There are two security systems on F-bodies (one standard and the other optional) and neither one is even remotely related to the radio. Both are controlled by the Body Control Module (BCM).

First, you have the Vehicle Anti-Theft System (VATS) which is the system that checks for the correct ignition key by measuring the resistance in the pellet on the key. It is designed to prevent the car from starting or running if the correct key isn't used by disabling the starter relay and turning off the fuel pump. It controls the SECURITY light in the instrument cluster. If the light is on, it is reading an incorrect resistance. If the light is flashing, it is unable to read any resistance (key pellet is missing or damaged).

Second, the optional Content Theft Deterrent (CTD) system is a basic alarm system. It flashes the lights and honks the horn if a door is opened or the car is struck while it's armed. It controls the red LED mounted on top of the dash to the right of the defroster vent.

(There is a third "security" system in the factory radio called TheftLock. If activated, it is supposed to prevent the radio from working if removed from the car. It is completely self-contained in the radio and is not connected to the rest of the car in any way.)

If your SECURITY light is on but the car still starts then you have one of two situations. It could be the system is reading the resistance in the key pellet and that the reading is close but not within the tolerance of the system. This is usually caused by dirt and grime build-up on the pellet contacts or on the contacts inside the ignition cylinder. Cleaning the key with rubbing alcohol and a pencil eraser, then cleaning the cylinder with spray electronic contact cleaner (available at Radio Shack) will often solve the problem. It also might be caused by worn contacts on the key or in the cylinder in which case you should get a new key or cylinder before it gets so worn that the VATS will prevent starting the car.

The other possibility is the the VATS has been bypassed the wrong way. The VATS can be bypassed using inline resistors to make the system think the correct key is always present. But some people bypass it by programming the PCM to ignore the fuel enable signal from the BCM and by grounding the starter relay coil lead. This allows the car to start but the SECURITY light will be always on.

The horn honking is usually caused by a bad shock sensor. It is located under the trim in the right quarter panel on the wheelwell in front of the spare tire. Unplug it and see if the problem goes away. Then you can decide if yu want to replace it or just leave it disconnected. You can also program the alarm system off using the instructions in your owner's manual or posted here.

 

mmmm then i guess am wrong...but when i changed my radio it came on and when i remove the radio fuse it goes off...

 

The RADIO fuse also provides power to the BCM so removing it would cause the BCM to stop lighting the SECURITY light.

 

I followed the instructions to program the alarm off and the car still does the same thing.

I unplugged the shock sensor and it fixed it, the doors lock but now the alarm dosent go off. Thanks for the help