Alarm and door lock malfunction 1996 Camaro z28 LT1

You need to visit an auto electrician, an alarm installer or an auto locksmith. The key fob needs re-pairing to the locking system.

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To arm content theft alarm.
1. Open the door.
2. Lock the door with the power door lock switch or
the remote keyless entry transmitter. The
SECURITY light should flash.
3. Close all doors. The SECURITY light should go off
after approximately 30 seconds. The alarm is not
armed until the SECURITY light goes off.

If a locked door is opened without the key or the remote keyless entry transmitter, the alarm will go off. The headlamps and parking lamps will flash for two minutes, and the horn will sound for 30 seconds, then will turn off to save the battery power.

Door Key Switch
The BCM monitors the door key switches in order to disarm the CTD system. When the lock cylinder turns in order to unlock the door, the switch grounds the disarm input to the BCM.
The key lock input to the BCM is probably missing , BCM doesn't see it . So it think's your breaking into the vehicle. Did you try the passenger door to see if it will disable the alarm .
The BCM - body control module ! Electronic -computer !
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Content Theft Deterrent (CTD) Does Not Disarm with Key Lock

The factory service repair manual has a 23 step diagnostic procedure . An you would need a factory scan tool to find the correct fix.
Turn ON the ignition with the engine OFF.
With a scan tool, observe the door key switch parameter in the Body Control Module (BCM) security data list.
Does the scan tool display INACTIVE?

Locking the Vehicle Without Arming the System
Use one of the following procedures in order to lock the vehicle without arming the system:
• Procedure A -- Lock the vehicle using the manual door lock knobs. Close all the doors.
• Procedure B -- Close all the doors. Use the key or the power door lock switch in order to lock the door. The doors must be closed prior to locking the doors for this procedure.
Disarming the System
In the arm initiated mode, the following conditions are true:
• The security telltale is ON.
• The doors are open.
In order to disarm a system in the arm initiated mode, perform one of the following procedures:
• Press the power door lock switch to the UNLOCK position.
• Press the door unlock button on the key fob.
In order to disarm a system in the arm delay or the armed mode, perform one of the following procedures:
• Use the key in order to unlock one of the doors.
• Press the door unlock button on the key fob.
Deactivating the Alarm
In the alarm mode, the following conditions are true:
• The horns sound intermittently.
• The headlights and the park lamps are flashing.
In order to deactivate a system in the alarm mode, perform one of the following procedures:
• Use the key in order to unlock one of the doors.
• Press the door unlock button on the key fob.
• If the vehicle control module (VCM)/powertrain control module (PCM) receives a valid Passlock™ ignition key rotation.

Check to see if your vehicle honks when you press the "lock" button on your key fob. Press the "lock" button multiple times in a row. Many devices won't beep unless you double-tap the button after locking. If the horn doesn't honk, but the lights flash, your chirp feature is probably disabled.

Use your keyless fob and ignition key to enable the audible chirp. The process varies considerably on different makes and models. You must usually consult your owner's manual, a dealership or the alarm manufacturer for the correct process.

it sounds like security start relay malfunction ,check and or change out relay.

I would start by replacing the FOB. Sounds to like the electronics inside it are bad. The only reason the horns would go off is if you hit the panic button. There is a slight chance the receiver is bad. But Fobs are cheaper to replace than the receivers. If you have two FOBs and they both react the same, then replace the receiver. Or just ditch the system. The keys (in the door locks) should still activate the alarm system.

hold the lock and unlck buttons simutaneously on the fob until you hear the the horn beep.this should do it!you may have inadvertantly changed the modes by accindentally doing the same...kinda like **** dialing your cell phone! if this doesnt do it may have blown fuse or horn for security system may have failed.you did say doors lock but horn doesnt sound right?

If you lock your doors with the remote, you have to use the remote to unlock them or it set off the alarm. I don't know why the manufacturers designed it that way(kind of stupid)but it's programmed into the on board computer. You can't disable the alarm without creating a worse problem somewhere else.

My 4Runner did the same thing. What I did was just put a new battery in hook it up and let it honk. Put the key in the ignition and start it and it should stop. It is in alarm mode.