2008 GMC YUKON ECU

Front Seats......................................................1-2
Manual Seats................................................1-2
Power Seats..................................................1-3
Manual Lumbar..............................................1-4
Power Lumbar...............................................1-4
Heated Seats.................................................1-5
Memory Seat, Mirrors, and Pedals....................1-6
Reclining Seatbacks........................................1-8
Head Restraints............................................1-10
Center Seat.................................................1-11
Rear Seats.....................................................1-11
Heated Seats...............................................1-11
60/40 Split Bench Seat (Second Row).............1-12
Bucket Seats (Second Row)...........................1-18
Third Row Seat............................................1-25
Safety Belts...................................................1-30
Safety Belts: They Are for Everyone................1-30
How to Wear Safety Belts Properly.................1-35
Lap-Shoulder Belt.........................................1-43
Safety Belt Use During Pregnancy..................1-49
Lap Belt......................................................1-49
Safety Belt Extender.....................................1-50
Child Restraints.............................................1-51
Older Children..............................................1-51
Infants and Young Children............................1-54
Child Restraint Systems.................................1-57Where to Put the Restraint.............................1-60
Lower Anchors and Tethers for
Children (LATCH)......................................1-61
Securing a Child Restraint in a Rear Seat
Position...................................................1-69
Securing a Child Restraint in the Center
Front Seat Position....................................1-71
Securing a Child Restraint in the Right
Front Seat Position....................................1-72
Airbag System...............................................1-76
Where Are the Airbags?
................................1-78
When Should an Airbag Inate?.....................1-81
What Makes an Airbag Inate?.......................1-83
How Does an Airbag Restrain?.......................1-83
What Will You See After an Airbag Inates?.....1-84
Passenger Sensing System............................1-85
Servicing Your Airbag-Equipped Vehicle...........1-90
Adding Equipment to Your Airbag-Equipped
Vehicle....................................................1-90
Restraint System Check..................................1-92
Checking the Restraint Systems......................1-92
Replacing Restraint System Parts
After a Crash............................................1-93
Section 1 Seats and Restraint Systems
1-1

{CAUTION:
A seat that is not locked into place properly
can move around in a collision or sudden stop.
People in the vehicle could be injured. Be sure
to lock the seat into place properly when
installing it.
4. Push and pull on the seat to make sure it is locked
into place. The seatback cannot be raised to the
upright position unless the seat is secured to
the oor.
5. Pull up on the seatback until it locks into the upright
position.
{CAUTION:
If the 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 seatback to be sure it is
locked.6. Push and pull on the seatback to make sure it is
locked.
{CAUTION:
A safety 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 safety belts are properly
routed and attached, and are not twisted.
7. Make sure the safety belts are returned to the
original position over the seatbacks.
1-29

Lap-Shoulder Belt
All seating positions in your vehicle have a lap-shoulder
except for the center front passenger position, if your
vehicle has one, which has a lap belt. SeeLap Belt on
page 1-49for more information.
Here is how to wear a lap-shoulder belt properly.
1. Adjust the seat, if the seat is adjustable, so you can
sit up straight. To see how, see “Seats” in the
Index.
2. Pick up the latch plate and pull the belt across you.
Do not let it get twisted.
The lap-shoulder belt may lock if you pull the belt
across you very quickly. If this happens, let the belt
go back slightly to unlock it. Then pull the belt
across you more slowly.
If you ever pull the shoulder portion of a passenger
belt out all the way, you may engage the child
restraint locking feature. If this happens, just let the
belt go back all the way and start again.
Engaging the child restraint locking feature may
affect the passenger sensing system. See
Passenger Sensing System on page 1-85.3. Push the latch plate into the buckle until it clicks. If
you nd 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, seeSafety Belt
Extender on page 1-50.
Make sure the release button on the buckle is
positioned so you would be able to unbuckle the
safety belt quickly if necessary.
1-43

To make the belt shorter, pull its free end as shown
until the belt is snug.
If the belt is not long enough, seeSafety Belt Extender
on page 1-50.
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 nd 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/retailer 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 t. 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.
1-50

Infants and Young Children
Everyone in a vehicle needs protection! This includes
infants and all other children. Neither the distance
traveled nor the age and size of the traveler changes
the need, for everyone, to use safety restraints. In fact,
the law in every state in the United States and in
every Canadian province says children up to some age
must be restrained while in a vehicle.
{CAUTION:
Children can be seriously injured or strangled if
a shoulder belt is wrapped around their neck
and the safety belt continues to tighten. Never
leave children unattended in a vehicle and never
allow children to play with the safety belts.
Every time infants and young children ride in vehicles,
they should have the protection provided by appropriate
restraints. Children who are not restrained properly
can strike other people, or can be thrown out of
the vehicle. In addition, young children should not use
the vehicle’s adult safety belts alone; they need to use a
child restraint.
{CAUTION:
People should never hold an infant in their
arms while riding in a vehicle. An infant does
not weigh much — until a crash. During a
crash an infant will become so heavy it is not
possible to hold it. For example, in a crash at
only 25 mph (40 km/h), a 12 lb (5.5 kg) infant
will suddenly become a 240 lb (110 kg) force
on a person’s arms. An infant should be
secured in an appropriate restraint.
1-54

Q:What are the different types of add-on child
restraints?
A:Add-on child restraints, which are purchased by the
vehicle’s owner, are available in four basic types.
Selection of a particular restraint should take
into consideration not only the child’s weight, height,
and age but also whether or not the restraint will
be compatible with the motor vehicle in which it will
be used.
For most basic types of child restraints, there are
many different models available. When purchasing a
child restraint, be sure it is designed to be used
in a motor vehicle. If it is, the restraint will have a
label saying that it meets federal motor vehicle
safety standards.
The restraint manufacturer’s instructions that come
with the restraint state the weight and height
limitations for a particular child restraint. In addition,
there are many kinds of restraints available for
children with special needs.
{CAUTION:
Newborn infants need complete support,
including support for the head and neck. This
is necessary because a newborn infant’s neck
is weak and its head weighs so much
compared with the rest of its body. In a crash,
an infant in a rear-facing seat settles into the
restraint, so the crash forces can be
distributed across the strongest part of an
infant’s body, the back and shoulders. Infants
should always be secured in appropriate infant
restraints.
1-56

{CAUTION:
The body structure of a young child is quite
unlike that of an adult or older child, for whom
the safety belts are designed. A young child’s
hip bones are still so small that the vehicle’s
regular safety belt may not remain low on the
hip bones, as it should. Instead, it may settle
up around the child’s abdomen. In a crash, the
belt would apply force on a body area that is
unprotected by any bony structure. This alone
could cause serious or fatal injuries. Young
children should always be secured in
appropriate child restraints.
Child Restraint Systems
A rear-facing infant
seat (A) provides restraint
with the seating surface
against the back of
the infant.
The harness system holds the infant in place and, in a
crash, acts to keep the infant positioned in the restraint.
A forward-facing child
seat (B) provides restraint
for the child’s body
with the harness.
1-57

A booster seat (C-D) is a child restraint designed to
improve the t of the vehicle’s safety belt system.
A booster seat can also help a child to see out the
window.
Securing an Add-On Child Restraint in
the Vehicle
{CAUTION:
A child can be seriously injured or killed in a
crash if the child restraint is not properly
secured in the vehicle. Make sure the child
restraint is properly installed in the vehicle
using the vehicle’s safety belt or LATCH
system, following the instructions that came
with that restraint, and also the instructions in
this manual.
To help reduce the chance of injury, the child restraint
must be secured in the vehicle. Child restraint systems
must be secured in vehicle seats by lap belts or the
lap belt portion of a lap-shoulder belt, or by the LATCH
system. SeeLower Anchors and Tethers for Children
(LATCH) on page 1-61for more information. A child can
be endangered in a crash if the child restraint is not
properly secured in the vehicle.
1-58