2012 GMC YUKON ECU

Black plate (16,1)GMC Yukon/Yukon XL Owner Manual - 2012
2-16 Keys, Doors, and Windows
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 the theft-deterrent
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. At this time,
you may also want to check the
fuse. SeeFuses and Circuit
Breakers on page 10‑40. 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 who
can service the PASS-Key III+ to
have a new key made.
It is possible for the PASS-Key III+
decoder to learn the transponder
value of a new or replacement key.
Up to 10 keys may be programmed
for the vehicle. The following procedure is for programming
additional keys only. If all the
currently programmed keys are lost
or do not operate, you must see
your dealer or a locksmith who can
service PASS-Key III+ to have keys
made and programmed to the
system.
See your dealer or a locksmith who
can service PASS-Key III+ to get a
new key blank cut exactly as the
ignition key that operates the
system.
To program the new additional key:
1. Verify that the new key has a
1
stamped on it.
2. Insert the original, already programmed key in the ignition
and start the engine. If the
engine will not start, see your
dealer for service.
3. After the engine has started, turn the key to LOCK/OFF, and
remove the key. 4. Insert the new key to be
programmed and turn it to the
ON/RUN position within
five seconds of turning the
ignition to the LOCK/OFF
position in Step 3.
The security light will turn off
once the key has been
programmed.
5. Repeat Steps 1 through 4 if additional keys are to be
programmed.
If you lose or damage your
PASS-Key III+ key, see your dealer
or a locksmith who can service
PASS-Key III+ to have a new
key made.
Do not leave the key or device that
disarms or deactivates the
theft-deterrent system in the vehicle.

Black plate (1,1)GMC Yukon/Yukon XL Owner Manual - 2012
Seats and Restraints 3-1
Seats and
Restraints
Head Restraints
Head Restraints . . . . . . . . . . . . . . . 3-2
Front Seats
Seat Adjustment . . . . . . . . . . . . . . 3-3
Center Seat . . . . . . . . . . . . . . . . . . . 3-4
Power Seat Adjustment . . . . . . . 3-4
Lumbar Adjustment . . . . . . . . . . . 3-4
Reclining Seatbacks . . . . . . . . . . 3-5
Memory Seats . . . . . . . . . . . . . . . . 3-7
Heated and Ventilated FrontSeats . . . . . . . . . . . . . . . . . . . . . . . . 3-9
Rear Seats
Heated Rear Seats . . . . . . . . . . 3-10
Second Row Seats . . . . . . . . . . 3-11
Third Row Seats . . . . . . . . . . . . . 3-16
Safety Belts
Safety Belts . . . . . . . . . . . . . . . . . . 3-20
How to Wear Safety BeltsProperly . . . . . . . . . . . . . . . . . . . . 3-21
Lap-Shoulder Belt . . . . . . . . . . . 3-22 Safety Belt Use During
Pregnancy . . . . . . . . . . . . . . . . . . 3-27
Lap Belt . . . . . . . . . . . . . . . . . . . . . 3-28
Safety Belt Extender . . . . . . . . . 3-28
Safety System Check . . . . . . . . 3-29
Safety Belt Care . . . . . . . . . . . . . 3-29
Replacing Safety Belt System Parts after a Crash . . . . . . . . . 3-29
Airbag System
Airbag System . . . . . . . . . . . . . . . 3-30
Where Are the Airbags? . . . . . 3-32
When Should an AirbagInflate? . . . . . . . . . . . . . . . . . . . . . 3-34
What Makes an Airbag Inflate? . . . . . . . . . . . . . . . . . . . . . 3-35
How Does an Airbag
Restrain? . . . . . . . . . . . . . . . . . . . 3-36
What Will You See after an Airbag Inflates? . . . . . . . . . . . . 3-36
Passenger Sensing System . . . . . . . . . . . . . . . . . . . . . 3-38
Servicing the Airbag-Equipped Vehicle . . . . . . . . . . . . . . . . . . . . . 3-42 Adding Equipment to the
Airbag-Equipped Vehicle . . . 3-42
Airbag System Check . . . . . . . . 3-44
Replacing Airbag System Parts after a Crash . . . . . . . . . 3-44
Child Restraints
Older Children . . . . . . . . . . . . . . . 3-45
Infants and Young
Children . . . . . . . . . . . . . . . . . . . . 3-47
Child Restraint Systems . . . . . 3-50
Where to Put the Restraint . . . 3-51
Lower Anchors and Tethers for Children (LATCH
System) . . . . . . . . . . . . . . . . . . . . 3-53
Replacing LATCH System Parts After a Crash . . . . . . . . . 3-60
Securing Child Restraints (Rear Seat Position) . . . . . . . . 3-60
Securing Child Restraints (Center Front Seat
Position) . . . . . . . . . . . . . . . . . . . 3-63
Securing Child Restraints (Right Front Seat
Position) . . . . . . . . . . . . . . . . . . . 3-63

Black plate (24,1)GMC Yukon/Yukon XL Owner Manual - 2012
3-24 Seats and Restraints
3. Push the latch plate into thebuckle until it clicks. If you find
that the latch plate will not go
fully into the buckle, see if you
are using the correct buckle.
Pull up on the latch plate to
make sure it is secure. If the belt
is not long enough, see Safety
Belt Extender on page 3‑28.
Position the release button on
the buckle so that the safety belt
could be quickly unbuckled if
necessary. 4. If equipped with a shoulder belt
height adjuster, move it to the
height that is right for you. See
“Shoulder Belt Height Adjuster”
in this section for instructions on
use and important safety
information.
5. To make the lap part tight, pull
up on the shoulder belt.
It may be necessary to pull
stitching on the safety belt
through the latch plate to fully
tighten the lap belt on smaller
occupants. To unlatch the belt, push the button
on the buckle. The belt should
return to its stowed position.
Before a door is closed, be sure the
safety belt is out of the way. If a
door is slammed against a safety
belt, damage can occur to both the
belt and the vehicle.
Shoulder Belt Height Adjuster
The vehicle has a shoulder belt
height adjuster for the driver and
right front passenger positions.
Adjust the height so the shoulder
portion of the belt is on the shoulder
and not falling off of it. The belt
should be close to, but not
contacting, the neck. Improper
shoulder belt height adjustment
could reduce the effectiveness of
the safety belt in a crash. See
How
to Wear Safety Belts Properly on
page 3‑21.

Black plate (28,1)GMC Yukon/Yukon XL Owner Manual - 2012
3-28 Seats and Restraints
Lap Belt
This part is only for the lap belt. To
learn how to wear a lap-shoulder
belt, seeLap-Shoulder Belt on
page 3‑22.
The vehicle may have a center
seating position. When you sit in the
center front seating position, you
have a lap safety belt, which has no
retractor.
To make the belt longer, tilt the latch
plate and pull it along the belt. Buckle, position and release it the
same way as the lap part of a
lap-shoulder belt.
To make the belt shorter, pull its free
end as shown until the belt is snug.
If the belt is not long enough, see
Safety Belt Extender on page 3‑28.
Make sure the release button on the
buckle is positioned so you would
be able to unbuckle the safety belt
quickly if necessary.
If you find that the latch plate will
not go fully into the buckle, see if
you are using the correct buckle. Be
sure that the latch plate clicks when
inserted into the buckle.
Safety Belt Extender
If the vehicle's safety belt will fasten
around you, you should use it.
But if a safety belt is not long
enough, your dealer will order you
an extender. When you go in to
order it, take the heaviest coat you
will wear, so the extender will be
long enough for you. To help avoid
personal injury, do not let someone
else use it, and use it only for the
seat it is made to fit. The extender
has been designed for adults. Never
use it for securing child seats. To
wear it, attach it to the regular safety
belt. For more information, see the
instruction sheet that comes with
the extender.

Black plate (31,1)GMC Yukon/Yukon XL Owner Manual - 2012
Seats and Restraints 3-31
{WARNING
Because airbags inflate with great
force and faster than the blink of
an eye, anyone who is up
against, or very close to any
airbag when it inflates can be
seriously injured or killed. Do not
sit unnecessarily close to any
airbag, as you would be if sitting
on the edge of the seat or leaning
forward. Safety belts help keep
you in position before and during
a crash. Always wear a safety
belt, even with airbags. The driver
should sit as far back as possible
while still maintaining control of
the vehicle.
Occupants should not lean on or
sleep against the door or side
windows in seating positions with
seat-mounted side impact airbags
and/or roof-rail airbags.
{WARNING
Children who are up against,
or very close to, any airbag
when it inflates can be seriously
injured or killed. Airbags plus
lap-shoulder belts offer protection
for adults and older children, but
not for young children and infants.
Neither the vehicle safety belt
system nor its airbag system is
designed for them. Young
children and infants need the
protection that a child restraint
system can provide. Always
secure children properly in the
vehicle. To read how, seeOlder
Children on page 3‑45 orInfants
and Young Children on
page 3‑47.
There is an airbag readiness light
on the instrument panel cluster,
which shows the airbag symbol.
The system checks the airbag
electrical system for malfunctions.
The light tells you if there is an
electrical problem. See Airbag
Readiness Light on page 5‑18 for
more information.

Black plate (33,1)GMC Yukon/Yukon XL Owner Manual - 2012
Seats and Restraints 3-33
Driver Side Shown, PassengerSide Similar
The roof-rail airbags for the driver,
right front passenger, and second
row outboard passengers are in the
ceiling above the side windows.Driver Side Shown, Passenger Side Similar
If the vehicle has a third row
passenger seat, the roof-rail airbags
are located in the ceiling above the
rear windows for the outboard
passenger positions in the third row.
{WARNING
If something is between an
occupant and an airbag, the
airbag might not inflate properly
or it might force the object into
that person causing severe injury
or even death. The path of an
inflating airbag must be kept
clear. Do not put anything
between an occupant and an
airbag, and do not attach or put
anything on the steering wheel
hub or on or near any other
airbag covering.
Do not use seat accessories that
block the inflation path of a
seat-mounted side impact airbag.
Never secure anything to the roof
of a vehicle with roof-rail airbags
by routing a rope or tie‐down
through any door or window
opening. If you do, the path of an
inflating roof-rail airbag will be
blocked.

Black plate (38,1)GMC Yukon/Yukon XL Owner Manual - 2012
3-38 Seats and Restraints
Passenger Sensing
System
If the vehicle has the passenger
airbag status indicator pictured in
the following illustration, then the
vehicle has a passenger sensing
system for the right front passenger
position. The passenger airbag
status indicator, if equipped, is
visible on the overhead console
when the vehicle is started.
In addition, if the vehicle has a
passenger sensing system for the
right front passenger position, the
label on the vehicle's sun visors
refers to“ADVANCED AIRBAGS”.
United States
Canada
The words ON and OFF, or the
symbols for on and off, will be
visible during the system check.
If you are using remote start,
if equipped, to start the vehicle from
a distance, you may not see the
system check. When the system
check is complete, either the word
ON or OFF, or the symbol for on or
off, will be visible. See Passenger
Airbag Status Indicator on
page 5‑19.
The passenger sensing system will
turn off the right front passenger
frontal airbag under certain
conditions. The driver airbag,
seat‐mounted side impact airbags
(if equipped) and the roof-rail
airbags are not affected by the
passenger sensing system. The passenger sensing system
works with sensors that are part
of the right front passenger seat
and safety belt. The sensors are
designed to detect the presence of
a properly-seated occupant and
determine if the right front
passenger frontal airbag should be
enabled (may inflate) or not.
According to accident statistics,
children are safer when properly
secured in a rear seat in the correct
child restraint for their weight
and size.
We recommend that children be
secured in a rear seat, including:
an infant or a child riding in a
rear-facing child restraint; a child
riding in a forward-facing child seat;
an older child riding in a booster
seat; and children, who are large
enough, using safety belts.
A label on the sun visor says,
“Never put a rear-facing child seat in
the front.”
This is because the risk to
the rear-facing child is so great,
if the airbag deploys.

Black plate (39,1)GMC Yukon/Yukon XL Owner Manual - 2012
Seats and Restraints 3-39
{WARNING
A child in a rear-facing child
restraint can be seriously injured
or killed if the right front
passenger airbag inflates. This is
because the back of the
rear-facing child restraint would
be very close to the inflating
airbag. A child in a forward-facing
child restraint can be seriously
injured or killed if the right front
passenger airbag inflates and the
passenger seat is in a forward
position.
Even if the passenger sensing
system has turned off the right
front passenger frontal airbag, no
system is fail-safe. No one can
guarantee that an airbag will not
deploy under some unusual
circumstance, even though the
airbag is turned off.(Continued)
WARNING (Continued)
Secure rear-facing child
restraints in a rear seat, even if
the airbag is off. If you secure a
forward-facing child restraint in
the right front seat, always move
the front passenger seat as far
back as it will go. It is better to
secure the child restraint in a
rear seat.
The passenger sensing system is
designed to turn off the right front
passenger frontal airbag if:
.The right front passenger seat is
unoccupied.
.The system determines an infant
is present in a child restraint.
.A right front passenger takes
his/her weight off of the seat for
a period of time.
.There is a critical problem with
the airbag system or the
passenger sensing system.
When the passenger sensing
system has turned off the right front
passenger frontal airbag, the off
indicator will light and stay lit as a
reminder that the airbag is off. See
Passenger Airbag Status Indicator
on page 5‑19.
The passenger sensing system is
designed to turn on (may inflate) the
right front passenger frontal airbag
anytime the system senses that a
person of adult size is sitting
properly in the right front
passenger seat.
When the passenger sensing
system has allowed the airbag to be
enabled, the on indicator will light
and stay lit as a reminder that the
airbag is active.