GMC Sierra 2018 Owner's Manual page 44

the lights will flash to indicate
pre-alarm. If the vehicle is not
started, or the door is not unlocked
by pressing on the RKE
transmitter during the 10-second
pre-alarm, the alarm will be
activated.
The alarm will also be activated if a
passenger door, the tailgate, or the
hood is opened without first
disarming the system. When the
alarm is activated, the turn signals
flash and the horn sounds for about
30 seconds. The alarm system will
then re-arm to monitor for the next
unauthorized event.
Disarming the Alarm System
To disarm the alarm system or turn
off the alarm if it has been activated:
Press on the RKE transmitter.
Start the vehicle.
To avoid setting off the alarm by
accident:
Lock the vehicle after all
occupants have exited.
Always unlock a door with the
RKE transmitter.
Unlocking the driver door with
the key will not disarm the
system or turn off the alarm.
How to Detect a Tamper
Condition
If is pressed on the RKE
transmitter and the horn chirps three
times, an alarm occurred previously
while the alarm system was armed.
If the alarm has been activated, a
message will appear on the DIC.
Inclination Sensor and
Intrusion Sensor
In addition to the standard
theft-deterrent system features, this
system may also have an,
inclination sensor and intrusion
sensor.
The inclination sensor can set off
the alarm if it senses movement of
the vehicle, such as a change in
vehicle orientation.
Keys, Doors, and Windows
The intrusion sensor monitors the
vehicle interior, and can activate the
alarm if it senses unauthorized entry
into the vehicle s interior. Do not
allow passengers or pets to remain
in the vehicle when the intrusion
sensor is activated.
Before arming the theft-deterrent
system and activating the intrusion
sensor:
Make sure all doors and
windows are completely closed.
Secure any loose items such as
sunshades.
Make sure there are no
obstructions blocking the
sensors in the front overhead
console.
Close DVD screens, if equipped,
before leaving the vehicle.
43