GMC 2009 Sierra - Manual (Page 95)

If a locked door is opened without using the RKE
transmitter, a ten second pre-alarm will occur. The horn
will chirp and the lights will flash. If the key is not
placed in the ignition and turned to START or the door
is not unlocked by pressing the unlock button on the
RKE transmitter during the ten second pre-alarm,
the alarm will go off. Your vehicle’s headlamps will flash
and the horn will sound for about two minutes, then
will turn off to save the battery power.
The theft-deterrent system will not activate if the doors
are locked with the vehicle’s key or the manual door lock.
It activates only if you use the power door lock switch with
the door open or the RKE transmitter. You should also
remember that you can start your vehicle with the correct
ignition key if the alarm has been set off.
To avoid setting off the alarm by accident:
• 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 RKE transmitter.
Unlocking a door any other way will set off the alarm
if the system has been armed.
If you set off the alarm by accident, press unlock on the
RKE transmitter or place the key in the ignition and
turn it to START to turn it off.
Testing the Alarm
To test the alarm:
1. From inside the vehicle, lower the driver’s window
and open the driver’s door.
2. Activate the system by locking the doors with the
RKE transmitter.
3. Get out of the vehicle, close the door and wait for
the security light to go out.
4. Then reach in through the window, unlock the door
with the manual door lock and open the door. This
should set off the alarm.
If the alarm does not sound when it should but the
headlamps flash, check to see if the horn works. The
horn fuse may be blown. To replace the fuse, see Fuses
and Circuit Breakers on page 5-108.
If the alarm does not sound or the headlamps do not
flash, see your dealer/retailer for service.
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