2008 GMC SIERRA Owner's Manual

Rear Doors
Extended Cab
Your vehicle may have a rear access door(s) that allows
easier access to the rear area of the extended cab.
To open a rear access
door from the outside, rst
open the front door.
Then, use the handle
located on the front edge
of the rear access door
to open it.
You must fully close a rear access door before you can
close the front door.To open a rear access
door from the inside, the
front door must be opened
rst. Then, use the
handle located on the
inside of the rear access
door to open.
Crew Cabs
If your vehicle is a crew cab, you can open your doors
from the inside or outside. Your vehicle may also
have a feature which prevents children from opening the
rear doors. SeeRear Door Security Locks on page 2-11
for more information.
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Tailgate
{CAUTION:
It is extremely dangerous to ride on the
tailgate, even when the vehicle is operated at
low speeds. People riding on the tailgate can
easily lose their balance and fall in response to
vehicle maneuvers. Falling from a moving
vehicle may result in serious injuries or death.
Do not allow people to ride on the tailgate. Be
sure everyone in your vehicle is in a seat and
using a safety belt properly.
On vehicles with a lock on the tailgate, use the key to
lock or unlock the tailgate.
Open the tailgate by lifting up on its handle while pulling
the tailgate toward you.
To shut the tailgate, rmly push it upward until it
latches.
After you put the tailgate back up, pull it back towards
you to be sure it latches securely.
Tailgate Removal
The tailgate can be removed to allow for different loading
situations. Although the tailgate can be removed without
assistance, you may want someone to assist you with the
removal to avoid possible damage to the vehicle.
To remove the tailgate, do the following:
1. Raise the tailgate
slightly and release
both retaining
cable clips. To release
the retaining cable
clips, lift the cable so it
points straight out.
Lift the clip over
the bolt, and push the
cable forward then
rotate down.
2. With the tailgate about halfway open, lift the right
edge of the tailgate from the lower pivot.
On vehicles with the tailgate assist feature, raise
the tailgate nearly all the way to the closed position
prior to removing the left edge.
3. Move the tailgate to the right to release the left edge.
Reverse this procedure to reinstall the tailgate. Make
sure the tailgate is secure.
2-14

Windows
{CAUTION:
Leaving children, helpless adults, or pets in a
vehicle with the windows closed is dangerous.
They can be overcome by the extreme heat
and suffer permanent injuries or even death
from heat stroke. Never leave a child, a
helpless adult, or a pet alone in a vehicle,
especially with the windows closed in warm or
hot weather.
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Manual Windows
Turn the hand crank on each door to manually raise or
lower the manual windows.
Power Windows
{CAUTION:
Leaving children, helpless adults, or pets in a
vehicle with the windows closed is dangerous.
They can be overcome from extreme heat in
warm or hot weather and suffer permanent
injuries or even death from heat stroke.
Leaving children in a vehicle with the ignition
key is dangerous for many reasons, children
or others could be badly injured or even killed.
They could operate the power windows or
other controls or even make the vehicle move.
The windows will function with the keys in the
ignition and they could be seriously injured or
CAUTION: (Continued)
CAUTION: (Continued)
killed if caught in the path of a closing window.
Do not leave keys in a vehicle with children.
When there are children in the rear seat use the
window lockout button to prevent unintentional
operation of the windows.
If your vehicle has power windows, the controls are
located on each of the side doors in the front and rear
for crew cab and extended cab models.Crew Cab shown
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The driver’s door has a switch for the passenger’s and
rear windows as well. Your power windows will work
when the ignition has been turned to ACCESSORY or
RUN or when Retained Accessory Power (RAP) is active.
SeeRetained Accessory Power (RAP) on page 2-23.
Press the switch down to lower the window, and pull up
the front of the switch to raise the window.
Express Down Windows
Vehicles with the express down feature allow the driver
and front passenger windows to be lowered without
holding the switch. Press down fully on the window
switch, then release, to activate the express down mode.
The express down mode can be canceled at any time
by pulling up on the switch. To open the window
partway, press the switch to the rst depression position,
until the window is at the desired position.
Window Lockout
o
(Window Lockout):If your crew cab or extended
cab vehicle has power windows, the driver’s door power
window switch has a lockout feature. The lockout switch
is located in front of the window switches. This feature
prevents the rear and passenger’s windows from
operating, except from the driver’s position. Press the
switch to engage or disengage the lockout feature. An
indicator light on the switch will come on when the lockout
feature is engaged, and will go off when disengaged.
Power Sliding Rear Window
On vehicles with a power
sliding rear window, the
switch is located in
the overhead console.
The power sliding rear window works when the ignition
has been turned to ACC/ACCESSORY, ON/RUN, or
when Retained Accessory Power (RAP) is active.
SeeRetained Accessory Power (RAP) on page 2-23for
more information.
The power sliding rear window cannot be operated
manually.
T:Press to open the window.
S:Press to close the window.
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Sun Visors
Pull the sun visor down to block glare. Swing the sun
visor to the side to cover the side window.
The passenger’s side sun visor may have a vanity
mirror.
Theft-Deterrent Systems
Vehicle theft is big business, especially in some cities.
Although your vehicle has a number of theft-deterrent
features, we know that nothing we put on it can make it
impossible to steal.
Content Theft-Deterrent
Your vehicle may have a content theft-deterrent alarm
system.
This is the security light.To arm the theft-deterrent system:
1. Open the door.
2. Lock the door with the Remote Keyless Entry (RKE)
transmitter. The security light should come on and
ash.
If the delayed locking feature is active, the alarm
will not be activated until all doors are closed
and the security light goes off.
3. Close all doors. The security light will stop ashing
and go off after approximately 30 seconds. The
content theft deterrent alarm is not armed until the
security light goes off.
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 ash. 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 ash
and the horn will sound for about two minutes, then
will turn off to save the battery power.
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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 ash, check to see if the horn works. The
horn fuse may be blown. To replace the fuse, seeFuses
and Circuit Breakers on page 5-123.
If the alarm does not sound or the headlamps do not
ash, see your dealer/retailer for service.
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PASS-Key®III+
The PASS-Key®III+ system operates on a radio
frequency subject to Federal Communications
Commission (FCC) Rules and with Industry Canada.
This device complies with Part 15 of the FCC Rules.
Operation is subject to the following two conditions:
1. This device may not cause harmful interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation.
This device complies with RSS-210 of Industry Canada.
Operation is subject to the following two conditions:
1. This device may not cause interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
Changes or modications to this system by other than
an authorized service facility could void authorization to
use this equipment.
PASS-Key
®III+ uses a radio frequency transponder in
the key that matches a decoder in your vehicle.
PASS-Key®III+ Operation
Your vehicle has PASS-Key®III+ (Personalized
Automotive Security System) theft-deterrent system.
PASS-Key
®III+ is a passive theft-deterrent system.
The system is automatically armed when the key
is removed from the ignition.
The system is automatically disarmed when the key is
turned to ON/RUN, ACC/ACCESSORY or START
from the LOCK/OFF position.
You do not have to manually arm or disarm the system.
The security light will come on if there is a problem
with arming or disarming the theft-deterrent system.
When the PASS-Key
®III+ system senses that someone
is using the wrong key, it prevents the vehicle from
starting. Anyone using a trial-and-error method to start
the vehicle will be discouraged because of the high
number of electrical key codes.
If the engine does not start and the security light on the
instrument panel cluster comes on when trying to
start the vehicle, there may be a problem with your
theft-deterrent system. Turn the ignition off and try again.
2-20