2006 GMC Sierra 1500 Pickup Owner's Manual - Page 114

The horn may chirp for 10 seconds before the alarm goes off if the theft-deterrent system is activated using the remote keyless entry transmitter and the driver's door is opened. If this occurs, you can turn off the alarm by pressing unlock on the remote keyless entry transmitter or by placing the key in the ignition and turning it to START. Here is how to avoid setting off the alarm by accident: Testing the Alarm The alarm can be tested by following these steps: 1. From inside the vehicle, activate the system by locking the doors with the remote keyless entry transmitter. 2. Wait for the security light to go out. 3. Unlock the door with the manual door lock and open the door. This should set off the alarm. 4. Turn off the alarm by pressing unlock on the remote keyless entry transmitter or by placing the key in the ignition and turning it to START. If the alarm does not sound when it should, but the vehicle's headlamps flash, check to see if the horn works. The horn fuse may be blown. To replace the fuse, see Instrument Panel Fuse Block on page 5-124 and Underhood Fuse Block on page 5-127. If the alarm does not sound or the vehicle's headlamps do not flash, see your dealer for service. • If you do not want to activate the theft-deterrent system, the vehicle should be locked with the door key after the doors are closed. • Always unlock a door with the remote keyless entry transmitter. If you set off the alarm by accident, turn off the alarm by pressing unlock on the remote keyless entry transmitter or by placing the key in the ignition and turning it to START. 2-20