GMC 2006 Sierra - Manual (Page 107)

Rear Door Security Locks
(Crew Cab)
With this feature, you can lock the rear side doors so that
they cannot be opened from the inside by passengers.
This feature is located
on the inside edge of
the rear doors.
To use one of the locks do the following:
1. Open one of the rear doors.
2. To engage the rear door security lock, move the
lever forward.
3. To disengage the lock, move the lever rearward.
4. Close the door.
5. Do the same thing to the other rear door.
The rear doors of your vehicle cannot be opened from
the inside when this feature is in use. If you want to
open the rear door while the security lock is engaged,
unlock the door and open the door from the outside.
Lockout Protection
This feature protects you from locking your key in
the vehicle when the key is in the ignition and a door
is open.
If the power lock switch is pressed when a door is open
and the key is in the ignition, all of the doors will lock and
then the driver’s door will unlock.
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