Immobilizer; Immobilizer Operation - GMC Sierra 2018 Owner's Manual

44 Keys, Doors, and Windows
Inclination and Intrusion
Sensors Disable Switch
It is recommended that the intrusion
and inclination sensors be
deactivated if pets are left in the
vehicle or if the vehicle is being
transported.
With the vehicle turned off, press
in the front overhead console.
The indicator light will come on
momentarily, indicating that these
sensors have been disabled for the
next alarm system arming cycle.

Immobilizer

See Radio Frequency Statement
0 459.

Immobilizer Operation

This vehicle has a passive
theft-deterrent system.
The system does not have to be
manually armed or disarmed.
The vehicle is automatically
immobilized when the vehicle is
turned off.
The system is automatically
disarmed when the ignition is turned
from off to on.
The security light, in the instrument
cluster, comes on if there is a
problem with arming or disarming
the theft-deterrent system.
When trying to start the vehicle, the
security light comes on briefly when
the ignition is turned on.
If the engine does not start and the
security light stays on, there is a
problem with the system. Turn the
ignition off and try again.
If the engine still does not start, and
the key appears to be undamaged,
try another ignition key. It may be
necessary to check the fuse. See
Fuses and Circuit Breakers 0 367.
If the engine still does not start with
the other key, the vehicle needs
service. If the vehicle does start, the
first key may be faulty. See your
dealer.
It is possible for the immobilizer
system to learn new or replacement
keys. Up to eight keys can be
programmed for the vehicle. To
program additional keys, see Keys
0 32. To program additional
transmitters, see your dealer.
Do not leave the key or device that
disarms or deactivates the vehicle
theft system in the vehicle.