Testing The Alarm - GMC 2002 Sonoma Owner's Manual

If a door is opened without the key or the remote
keyless entry transmitter, the alarm will go off.
Your vehicle's headlamps will flash and the horn will
sound for 110 seconds, then will turn off to save the
battery power.
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Remember, the theft deterrent system won't activate if
you lock the doors with a key or use the manual door
lock. It activates only if you use a power door lock
switch with the door open, or with the remote keyless
entry transmitter. You should also remember that you
can start your vehicle with the correct ignition key if the
alarm has been set off.
Here's how to avoid setting off the alarm by accident:
D
If you don't want to activate the theft
system, the vehicle should be locked with the door
key after the doors are closed.
D
Always unlock a door with a key, or use the remote
keyless entry transmitter. Unlocking a door any other
way will set off the alarm.
If you set off the alarm by accident, unlock any door
with the key. You can also turn off the alarm by pressing
UNLOCK on the remote keyless entry transmitter. The
alarm won't stop if you try to unlock a door any
other way.

Testing the Alarm

The alarm can be tested by following these steps:
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
power door lock switch while the door is open, or
with the remote keyless entry 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.
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deterrent
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 "Fuses and Circuit Breakers" in the Index.
If the alarm does not sound or the vehicle's headlamps
do not flash, the vehicle should be serviced by an
authorized service center.
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