2009 GMC YUKON ECO mode

j(Lower Anchor): Seating
positions with two lower
anchors.
i(Top Tether Anchor):
Seating positions with
top tether anchors.
i(Top Tether Anchor):
Seating positions with top
tether anchors.
i(Top Tether Anchor):
Seating positions with top
tether anchors. There is
one top tether anchor that
can be used for either
the third row center
or driver side seating
position but not both at
the same time.
For models with a three passenger third row seat, see
the information following for installing a child restraint
with a top tether in the third row, if your vehicle has one.
Never install two top tethers using the same top
tether anchor.
For models with 60/40 second row seating, the rear
right side passenger and center seating positions have
exposed metal anchors located in the crease between
the seatback and the seat cushion.
For models with second row bucket seats, both rear
seating positions have exposed metal anchors located
in the crease between the seatback and the seat
cushion. Second Row — Bucket
Third Row — Two
Passenger
Third Row — Three
Passenger
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For models with bucket second row seating, the top
tether anchors are located at the bottom rear of the seat
cushion for each seating position in the second row.
Be sure to use an anchor located on the same side of
the vehicle as the seating position where the child
restraint will be placed.For models with 60/40 second row seating, the top
tether anchors are located at the bottom rear of the seat
cushion for each seating position in the second row.
Be sure to use an anchor located on the same side of
the vehicle as the seating position where the child
restraint will be placed. Second Row Seat — Bucket
Second Row Seat — 60/40
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What Makes an Airbag Inate?
In a deployment event, the sensing system sends an
electrical signal triggering a release of gas from the
inator. Gas from the inator lls the airbag causing the
bag to break out of the cover and deploy. The inator, the
airbag, and related hardware are all part of the airbag
module.
Frontal airbag modules are located inside the steering
wheel and instrument panel. For vehicles with roof-rail
airbags, there are airbag modules in the ceiling of the
vehicle, near the side windows that have occupant
seating positions.
How Does an Airbag Restrain?
In moderate to severe frontal or near frontal collisions,
even belted occupants can contact the steering wheel
or the instrument panel. In moderate to severe side
collisions, even belted occupants can contact the inside
of the vehicle.
Airbags supplement the protection provided by safety
belts. Frontal airbags distribute the force of the impact
more evenly over the occupant’s upper body, stopping
the occupant more gradually. Roof-rail airbags distribute
the force of the impact more evenly over the occupant’s
upper body.Rollover capable roof-rail airbags are designed to help
contain the head and chest of occupants in the outboard
seating positions in the rst, second, and third rows, if
equipped with a third row seat. The rollover capable
roof-rail airbags are designed to help reduce the risk of
full or partial ejection in rollover events, although no
system can prevent all such ejections.
But airbags would not help in many types of collisions,
primarily because the occupant’s motion is not toward
those airbags. SeeWhen Should an Airbag Inflate? on
page 1-86for more information.
Airbags should never be regarded as anything more
than a supplement to safety belts.
What Will You See After an Airbag
Inates?
After the frontal airbags inate, they quickly deate,
so quickly that some people may not even realize an
airbag inated. Roof-rail airbags may still be at least
partially inated for some time after they deploy. Some
components of the airbag module may be hot for several
minutes. For location of the airbag modules, seeWhat
Makes an Airbag Inflate? on page 1-88.
1-88

Retained Accessory Power (RAP)
The following vehicle accessories can be used for up to
10 minutes after the engine is turned off:
Audio System
Power Windows
OnStar®System (if equipped)
Sunroof (if equipped)
These features work when the key is in ON/RUN or
ACC/ACCESSORY. Once the key is turned from
ON/RUN to LOCK/OFF, the windows and sunroof
continue to work up to 10 minutes until any door
is opened. The radio continues to work for up to
10 minutes or until the driver door is opened.
Starting the Engine
If the vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
Move the shift lever to P (Park) or N (Neutral). The
engine will not start in any other position. To restart the
engine when the vehicle is are already moving, use
N (Neutral) only.
Notice:Do not try to shift to P (Park) if the vehicle
is moving. If you do, you could damage the
transmission. Shift to P (Park) only when the vehicle
is stopped.
Starting Procedure
1. With your foot off the accelerator pedal, turn the
ignition key to START. When the engine starts, let go
of the key. The idle speed will go down as the engine
gets warm. Do not race the engine immediately after
starting it. Operate the engine and transmission
gently to allow the oil to warm up and lubricate all
moving parts.
The vehicle has a Computer-Controlled Cranking
System. This feature assists in starting the engine
and protects components. If the ignition key is turned
to the START position, and then released when the
engine begins cranking, the engine will continue
cranking for a few seconds or until the vehicle starts.
If the engine does not start and the key is held in
START for many seconds, cranking will be stopped
after 15 seconds to prevent cranking motor damage.
To prevent gear damage, this system also prevents
cranking if the engine is already running. Engine
cranking can be stopped by turning the ignition
switch to the ACC/ACCESSORY or LOCK/OFF
position.
Notice:Cranking the engine for long periods of
time, by returning the key to the START position
immediately after cranking has ended, can overheat
and damage the cranking motor, and drain the
battery. Wait at least 15 seconds between each try,
to let the cranking motor cool down.
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Active Fuel Management™
Vehicles with V8 engines may have Active Fuel
Management™. This system allows the engine to
operate on either all or half of its cylinders, depending
on the driving conditions.
When less power is required, such as cruising at a
constant vehicle speed, the system will operate in the half
cylinder mode, allowing the vehicle to achieve better fuel
economy. When greater power demands are required,
such as accelerating from a stop, passing, or merging
onto a freeway, the system will maintain full-cylinder
operation.
If your vehicle has an Active Fuel Management™
indicator, seeDIC Operation and Displays (With DIC
Buttons) on page 3-52orDIC Operation and Displays
(Without DIC Buttons) on page 3-57for more information
on using this display.
Automatic Transmission Operation
If the vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
If the vehicle is has an automatic transmission, it has an
electronic shift position indicator within the instrument
panel cluster. This display comes on when the ignition
key is turned to the ON/RUN position.
There are several different positions for the shift lever.
Hydra-Matic
®4-Speed
Automatic Transmission
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This shift stabilization feature is designed to determine,
before making an upshift, if the engine is able to maintain
vehicle speed by analyzing things such as vehicle speed,
throttle position, and vehicle load. If the shift stabilization
feature determines that a current vehicle speed cannot be
maintained, the transmission does not upshift and instead
holds the current gear. In some cases, this could appear
to be a delayed shift, however the transmission is
operating normally.
The vehicle’s transmission uses adaptive shift controls.
Adaptive shift controls continually compares key shift
parameters to pre-programmed ideal shifts stored in the
transmissions computer. The transmission constantly
makes adjustments to improve vehicle performance
according to how the vehicle is being used, such as with
a heavy load or when the temperature changes. During
this adaptive shift control process, shifting might feel
different as the transmission determines the best
settings.
When temperatures are very cold, the Hydra-Matic
®
6-Speed transmission’s gear shifting could be delayed
providing more stable shifts until the engine warms
up. Shifts could be more noticeable with a cold
transmission. This difference in shifting is normal.M (Manual Mode):This position is available on
vehicles with the Hydra-Matic
®6-Speed transmission.
It lets drivers select the range of gears appropriate
for current driving conditions. If the vehicle has
this feature, see Range Select Mode (Hydra-Matic
®
6-Speed transmission) later in this section.
3 (Third):This position is also used for normal driving.
It reduces vehicle speed more than D (Drive) without
using the brakes. You might choose 3 (Third) instead of
D (Drive) when driving on hilly, winding roads, when
towing a trailer, so there is less shifting between gears
and when going down a steep hill.
2 (Second):This position reduces vehicle speed even
more than 3 (Third) without using the brakes. You can
use 2 (Second) on hills. It can help control vehicle speed
as you go down steep mountain roads, but then you
would also want to use the brakes off and on.
If you manually select 2 (Second) in an automatic
transmission, the transmission will start in second gear.
You can use this feature for reducing the speed of the
rear wheels when you are trying to start the vehicle from
a stop on slippery road surfaces.
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1 (First):For the Hydra-Matic®4-Speed transmission
this position reduces vehicle speed even more than
2 (Second) without using the brakes. You can use it on
very steep hills, or in deep snow or mud. If the shift
lever is put in 1 (First) while the vehicle is moving
forward, the transmission does not shift into rst gear
until the vehicle is going slowly enough.
For a Hydra-Matic
®6-Speed transmission, this position
reduces vehicle speed without using the brakes. You can
use it for major/severe downgrades and off-road driving
where the vehicle would otherwise accelerate due to
steepness of grade. When you shift to 1 (First) it provides
the lowest gear appropriate to the vehicle’s current road
speed and continues to downshift as the vehicle slows,
eventually downshifting to 1 (First) gear.
Notice:Spinning the tires or holding the vehicle in
one place on a hill using only the accelerator pedal
may damage the transmission. The repair will not be
covered by the vehicle warranty. If you are stuck, do
not spin the tires. When stopping on a hill, use the
brakes to hold the vehicle in place.
Range Selection Mode (Hydra-Matic®
6-Speed Transmission)
The vehicle may have a Range Selection Mode. The
Range Selection Mode helps control the vehicle’s
transmission and vehicle speed while driving down hill
or towing a trailer by letting you select a desired range
of gears.
To use this feature, do the following:
1. Move the shift lever to M (Manual Mode).
2. Press the plus/minus buttons, located on the
steering column shift lever, to select the desired
range of gears for the current driving conditions.Base trim shown (uplevel similar)
2-33

When M (Manual Mode) is selected a number displays
next to the M, indicating the current gear.
This number is the highest gear that can be used.
However, the vehicle can automatically shift to lower
gears as it adjusts to driving conditions. This means
that all gears below that number are available. When
5 (Fifth) is selected, 1 (First) through 5 (Fifth) gears
are automatically shifted by the vehicle, but 6 (Sixth)
cannot be used until the plus/minus button located
on the steering column lever is used to change to
the gear.
Grade Braking is not available when Range Selection
Mode is active. SeeTow/Haul Mode on page 2-35
While using Range Selection Mode, cruise control and
the Tow/Haul mode can be used.Notice:Spinning the tires or holding the vehicle
in one place on a hill using only the accelerator
pedal may damage the transmission. The repair will
not be covered by the vehicle warranty. If you
are stuck, do not spin the tires. When stopping on a
hill, use the brakes to hold the vehicle in place.
Low Traction Mode
If the vehicle has the Hydra-Matic®6-Speed Automatic
Transmission, it has a Low Traction Mode that assists
in vehicle acceleration when road conditions are
slippery, such as with ice or snow. While the vehicle is
at a stop, select the second gear range using Range
Selection Mode. This will limit torque to the wheels after
it detects wheel slip, preventing the tires from spinning.
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