GMC SIERRA 2018 Repair Manual

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
60 Seats and Restraints
Power Seat Adjustment
To adjust a power seat, if equipped:
.Move the seat forward or
rearward by sliding the control
forward or rearward.
. If equipped, raise or lower the
front part of the seat cushion by
moving the front of the control
up or down.
. If equipped, raise or lower the
seat by moving the rear of the
control up or down.
To adjust the seatback, see
Reclining Seatbacks 061. To adjust the lumbar support, see
Lumbar Adjustment
060.
Some vehicles are equipped with a
feature that activates a vibrating
pulse alert in the driver seat to help
the driver avoid crashes. See Driver
Assistance Systems 0288.
Lumbar Adjustment
Manual Lumbar
If equipped, move the lever up or
down repeatedly to increase or
decrease lumbar support.
Power Lumbar
To adjust the power lumbar support,
if equipped:
.
Press and hold the control
forward to increase or rearward
to decrease upper and lower
lumbar support at the same time.
. If equipped, press and hold the
control up to increase upper
lumbar support and decrease
lower lumbar support.
Press and hold the control down
to increase lower lumbar support
and decrease upper lumbar
support.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Seats and Restraints 61
Reclining Seatbacks
{Warning
Sitting in a reclined position when
the vehicle is in motion can be
dangerous. Even when buckled
up, the seat belts cannot do
their job.
The shoulder belt will not be
against your body. Instead, it will
be in front of you. In a crash, you
could go into it, receiving neck or
other injuries.
The lap belt could go up over
your abdomen. The belt forces
would be there, not at your pelvic
bones. This could cause serious
internal injuries.
For proper protection when the
vehicle is in motion, have the
seatback upright. Then sit well
back in the seat and wear the
seat belt properly.
Do not have a seatback reclined if
the vehicle is moving.
Manual Reclining Seatbacks
{Warning
If either seatback is not locked, it
could move forward in a sudden
stop or crash. That could cause
injury to the person sitting there.
Always push and pull on the
seatbacks to be sure they are
locked.
To adjust a manual seatback:1. Lift the lever. The seatback will automatically
fold forward.
2. To recline, move the seatback rearward to the desired
position, then release the lever
to lock the seatback in place.
3. Push and pull on the seatback to make sure it is locked.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
62 Seats and Restraints
To return the seatback to the upright
position:1. Lift the lever fully without applying pressure to the
seatback, and the seatback will
return to the upright position.
2. Push and pull on the seatback to make sure it is locked.
Power Reclining Seatbacks
To recline a power seatback,
if equipped:
.Tilt the top of the control
rearward to recline. .
Tilt the top of the control forward
to raise.
Memory Seats
Crew/Double Cab Shown, Other
Models Similar
If equipped, memory seats allow two
drivers to store and recall their
unique seat positions for driving the
vehicle, and a shared exit position
for getting out of the vehicle. Other
feature positions may also be set,
such as power mirrors, power
steering wheel, and adjustable
pedals, if equipped. Memory positions are linked to RKE
transmitter 1 or 2 for automatic
memory recalls.
Before storing, adjust all available
memory feature positions. Turn the
ignition on and then press and
release SET; a beep will sound.
Then immediately press and hold 1,
2, or
B(Exit) on the driver door
until two beeps sound. To manually
recall these positions, press and
hold 1, 2, or
Buntil the saved
position is reached.
The vehicle identifies the current
driver ’s RKE transmitter number
(1–8). See Remote Keyless Entry
(RKE) System Operation 037. Only
RKE transmitters 1 and 2 can be
used for automatic memory recalls.
A Driver Information Center (DIC)
welcome message indicating the
transmitter number may display for
the first few ignition cycles following
a transmitter change. For Auto
Memory Recall to work properly,
save the positions to the memory
button (1 or 2) matching the RKE
transmitter number displayed in the

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Seats and Restraints 63
DIC welcome message. Carry the
linked RKE transmitter when
entering the vehicle.
Vehicle Personalization Settings
.To have the Auto Memory Recall
movement begin when the
vehicle is started, select the
Settings menu, then Vehicle,
then Comfort and Convenience,
and then Auto Memory Recall.
Select On or Off. See “Auto
Memory Recall” later in this
section.
. To begin Easy Exit Recall
movement when the ignition is
turned off and the driver door is
opened, or when the ignition is
turned off with the driver door
already opened, select the
Settings menu, then Vehicle,
then Comfort and Convenience,
and then Easy Exit Options.
Select On or Off. See “Easy Exit
Recall” later in this section.
. See Vehicle Personalization
0 165 for additional setting
information. Identifying Driver Number
To identify the driver number:
1. Start the vehicle with the other key or RKE transmitter. The
DIC should display the driver
number; 1 or 2. Turn the
ignition off and remove the key
or RKE transmitter from the
vehicle.
2. Start the vehicle with the initial key or RKE transmitter. The
DIC should display the other
driver number not shown in
step 1.
Saving Memory Positions
Read these instructions completely
before saving memory positions.
To save preferred driving positions
1 and 2: 1. Turn the ignition on or to ACC/ ACCESSORY.
A DIC welcome message may
be displayed indicating number
1 or 2 for memory recalls. 2. Adjust all available memory
features to the desired driving
position.
3. Press and release SET; a beep will sound.
4. Immediately press and hold the 1 or 2 memory button matching
the above DIC welcome
message until two beeps
sound.
If too much time passes
between releasing SET and
pressing 1, the memory
position will not be saved and
two beeps will not sound.
Repeat Steps 3 and 4.
1 or 2 corresponds to the driver
number. See “Identifying Driver
Number” in this section.
5. Repeat Steps 1–4 for a second driver using 1 or 2.
To save the position for
Band
easy exit features, repeat Steps 1–4
using
B. This stores the position
for getting out of the vehicle.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
64 Seats and Restraints
Save preferred memory feature
positions to both 1 and 2 if you are
the only driver.
Manually Recalling Memory
Positions
Press and hold 1, 2, or
Bto recall
the previously stored memory
positions.
To stop manual recall movement,
release 1, 2, or
B. Recall can also
be stopped by pressing a power
seat, SET, power mirror control,
power steering wheel control,
or adjustable pedal control,
if memory equipped. The driver or
passenger side mirror must be
selected.
Auto Memory Recall
The vehicle identifies the number of
the current driver ’s RKE transmitter
(1–8). See Remote Keyless Entry
(RKE) System Operation 037. If the
RKE transmitter is 1 or 2, and Auto
Memory Recall is programmed on in
vehicle personalization, the
positions saved to the same
memory button number 1 or 2 are automatically recalled when the
ignition is turned on, or turned from
off to ACC/ACCESSORY. RKE
transmitters 3–8 will not provide
automatic memory recalls.
To turn Auto Memory Recall on or
off, see "Vehicle Personalization
Settings" previously in this section
and
Vehicle Personalization 0165.
The transmission must be in
P (Park) to initiate Auto Memory
Recall. Auto Memory Recall will
complete if the vehicle is shifted out
of P (Park) prior to reaching the
stored memory position.
To stop Auto Memory Recall
movement, turn the ignition off or
press any of the following memory
controls:
. Power seat
. Memory SET, 1, 2, or
B
.Power mirror, with the driver or
passenger side mirror selected
. Power steering wheel,
if equipped
. Adjustable pedals, if equipped If the stored memory seat position
does not automatically recall or
recalls to the wrong positions, the
driver
’s RKE transmitter number
(1 or 2) may not match the memory
button number that positions were
saved to. Try storing the position to
the other memory button or try the
other RKE transmitter.
Easy Exit Recall
Easy Exit Recall is not linked to an
RKE transmitter. The position stored
to
Bis used for all drivers. To turn
Easy Exit Recall on or off, see
"Vehicle Personalization Settings"
previously in this section and
Vehicle Personalization 0165.
If turned on, the position saved to
Bis automatically recalled when
one of the following occurs:
. The vehicle is turned off and the
driver door is opened within a
short time.
. The vehicle is turned off with the
driver door open.

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Seats and Restraints 65
To stop Easy Exit Recall movement,
press any of the following memory
controls:
.Power seat
. Memory SET, 1, 2, or
B
.Power mirror, with the driver or
passenger side mirror selected
. Power steering wheel,
if equipped
. Adjustable pedals, if equipped
Obstructions
If something has blocked the driver
seat and/or power steering wheel
while recalling a memory position,
the recall may stop. Remove the
obstruction and try the recall again.
If the memory position still does not
recall, see your dealer for service.
Heated and Ventilated
Front Seats
{Warning
If temperature change or pain to
the skin cannot be felt, the seat
heater may cause burns. To
reduce the risk of burns, use care
when using the seat heater,
especially for long periods of
time. Do not place anything on
the seat that insulates against
heat, such as a blanket, cushion,
cover, or similar item. This may
cause the seat heater to
overheat. An overheated seat
heater may cause a burn or may
damage the seat.
Heated and Ventilated Seat
Buttons Shown, Heated Seat Buttons Similar
If equipped, the buttons are on the
center stack. To operate, the engine
must be running.
Press
Ito heat the driver or
passenger seatback only.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
66 Seats and Restraints
PressJto heat the driver or
passenger seat cushion and
seatback.
Press
Cto ventilate the driver or
passenger seat.
The indicator light on the button
comes on when this feature is on.
Press the button once for the
highest setting. With each press of
the button, the seat will change to
the next lower setting, and then to
the off setting. The indicator lights
next to the buttons indicate three for
the highest setting and one for the
lowest. If the heated seats are on
high for an extended time, their level
may automatically be lowered. Remote Start Auto Heated and
Ventilated Seats
During a remote start, the heated or
ventilated seats can be turned on
automatically. When it is cold
outside, the heated seats turn on,
and when it is hot outside the
ventilated seats turn on. The heated
or ventilated seats are canceled
when the ignition is turned on. Press
the heated or ventilated seat button
to use the heated or ventilated seats
after the vehicle is started.
The heated or ventilated seat
indicator lights do not turn on during
a remote start.
The temperature performance of an
unoccupied seat may be reduced.
This is normal.
The heated or ventilated seats will
not turn on during a remote start
unless they are enabled in the
vehicle personalization menu.
See
Remote Vehicle Start 039 and
Vehicle Personalization 0165.
Rear Seats
Rear Seats (Double Cab
Full Bench)
Rear Seat Reminder (Full
Bench Only)
If equipped, the message REAR
SEAT REMINDER LOOK IN REAR
SEAT displays under certain
conditions indicating there may be
an item or passenger in the rear
seat. Check before exiting the
vehicle.
This feature will activate when a
second row door is opened while
the vehicle is on or up to 10 minutes
before the vehicle is turned on.
There will be an alert when the
vehicle is turned off. The alert does
not directly detect objects in the rear
seat; instead, under certain
conditions, it detects when a rear
door is opened and closed,
indicating that there may be
something in the rear seat.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Seats and Restraints 67
The feature is active only once each
time the vehicle is turned on and off,
and will require reactivation by
opening and closing the second row
doors. There may be an alert even
when there is nothing in the rear
seat; for example, if a child entered
the vehicle through the rear door
and left the vehicle without the
vehicle being shut off.
The feature can be turned on or off.
SeeVehicle Personalization 0165.
Folding the Rear Seat
Caution
Folding a rear seat with the seat
belts still fastened may cause
damage to the seat or the seat
belts. Always unbuckle the seat
belts and return them to their
normal stowed position before
folding a rear seat.
To fold the seat:1. Pull up on the front of the seat cushion while pulling down on
the release strap loop under
the seat cushion.
2. Pull the seat cushion up until it latches with the seatback.
3. Pull forward on the seat cushion to make sure it is
locked in place. To unfold the seat:
1. Push the seat cushion rearward while pulling the
release strap loop under the
seat cushion. Pull the seat
cushion down until it latches.
2. Pull up on the seat cushion to make sure it is locked in place.
Make sure the seat belts are
not twisted or caught in the
seat cushion.
{Warning
A seat belt that is improperly
routed, not properly attached,
or twisted will not provide the
protection needed in a crash. The
person wearing the belt could be
seriously injured. After raising the
rear seatback, always check to be
sure that the seat belts are
properly routed and attached, and
are not twisted.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
68 Seats and Restraints
Rear Seats (Split Bench)
Folding the Rear Seat
Either side of the rear seat can be
folded for added cargo space.
Caution
Folding a rear seat with the seat
belts still fastened may cause
damage to the seat or the seat
belts. Always unbuckle the seat
belts and return them to their
normal stowed position before
folding a rear seat.
Make sure that nothing is on the
seat cushion.
To fold the seat, slowly pull the seat
cushion up.
To return the seat to the normal
seating position, slowly pull the seat
cushion down.
Make sure the seat belts are not
twisted or caught in the seat
cushion.
{Warning
A seat belt that is improperly
routed, not properly attached,
or twisted will not provide the
protection needed in a crash. The
person wearing the belt could be
seriously injured. After raising the
rear seatback, always check to be
sure that the seat belts are
properly routed and attached, and
are not twisted.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Seats and Restraints 69
Seat Belts
This section describes how to use
seat belts properly, and some things
not to do.
{Warning
Do not let anyone ride where a
seat belt cannot be worn properly.
In a crash, if you or your
passenger(s) are not wearing
seat belts, injuries can be much
worse than if you are wearing
seat belts. You can be seriously
injured or killed by hitting things
inside the vehicle harder or by
being ejected from the vehicle. In
addition, anyone who is not
buckled up can strike other
passengers in the vehicle.
It is extremely dangerous to ride
in a cargo area, inside or outside
of a vehicle. In a collision,
passengers riding in these areas
are more likely to be seriously
injured or killed. Do not allow(Continued)
Warning (Continued)
passengers to ride in any area of
the vehicle that is not equipped
with seats and seat belts.
Always wear a seat belt, and
check that all passenger(s) are
restrained properly too.
This vehicle has indicators as a
reminder to buckle the seat belts.
See Seat Belt Reminders 0146.
Seat Belt Assurance System
This vehicle may have the Seat Belt
Assurance System, which prevents
the vehicle from shifting out of
P (Park). A message displays in the
Driver Information Center (DIC)
indicating the shift lever is locked
when the brake pedal is applied and
the seat belts for either the driver or
front outboard passenger are not
buckled. The vehicle will not shift
out of P (Park). Buckle the seat
belts to unlock the shift lever. If the front passenger seat is unoccupied,
only the driver seat belt must be
buckled to unlock the shift lever.
This system may not allow the
vehicle to shift out of P (Park) if an
object
—such as a briefcase,
handbag, grocery bag, laptop,
or other electronic device —is on
the front outboard passenger seat.
If this happens, remove the object
from the seat or buckle the
seat belt.
If the driver or front outboard
passenger unbuckles their seat belt
while driving, the seat belt reminder
chime and light(s) will come on. See
Seat Belt Reminders 0146.
The Seat Belt Assurance System
will time out 30 seconds after the
brake pedal is initially pressed.
A message displays in the DIC
indicating the shift lever is unlocked
allowing the vehicle to be shifted out
of P (Park). See “Seat Belts”and
“Child Restraints” in the Index for
information about the importance of
proper restraint use.