2010 GMC YUKON ignition

Starting Procedure
1. With your foot off the accelerator pedal, turn theignition 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. 2. If the engine does not start after 5‐10 seconds,
especially in very cold weather (below 0°F or
−18°C), it could be flooded with too much gasoline.
Try pushing the accelerator pedal all the way to
the floor and holding it there as you hold the key
in START for up to a maximum of 15 seconds.
Wait at least 15 seconds between each try, to allow
the cranking motor to cool down. When the engine
starts, let go of the key and accelerator. If the
vehicle starts briefly but then stops again, do the
same thing. This clears the extra gasoline from the
engine. Do not race the engine immediately after
starting it. Operate the engine and transmission
gently until the oil warms up and lubricates all
moving parts.
Notice: The engine is designed to work with the
electronics in the vehicle. If you add electrical
parts or accessories, you could change the
way the engine operates. Before adding electrical
equipment, check with your dealer. If you do
not, the engine might not perform properly.
Any resulting damage would not be covered
by the vehicle warranty.
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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 the vehicle has an Active Fuel Management™
indicator, seeDIC Operation and Displays (With DIC
Buttons)
on page 4‑48or DIC Operation and Displays
(Without DIC Buttons)on page 4‑55for 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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Four-Wheel Drive (Two Speed
Automatic Transfer Case)
If the vehicle has four-wheel drive, you can send the
engine's driving power to all four wheels for extra
traction. Read the following before using four-wheel
drive.
Notice:Driving on clean, dry pavement in
Four-Wheel Drive High or Four-Wheel Drive Low for
an extended period of time may cause premature
wear on your vehicle's powertrain. Do not drive on
clean, dry pavement in Four-Wheel Drive High or
Four-Wheel Drive Low for extended periods of time.
While driving on clean dry pavement and during tight
turns, you may experience a vibration in the steering
system.
The vehicle has StabiliTrak
®. Shifting into
Four-Wheel-Drive Low will turn Traction Control and
StabiliTrak
®off. See StabiliTrak®System on page 5‑6.
Front Axle
The front axle engages and disengages automatically
when you shift the transfer case. Some delay for the
axle to engage or disengage is normal.
Automatic Transfer Case
The transfer case knob is
located to the left of the
instrument panel cluster.
Use this dial to shift into and out of four-wheel drive.
You can choose among five driving settings:
Indicator lights in the switches show you which setting
you are in. The indicator lights will come on briefly when
you turn on the ignition and the last chosen setting will
stay on. If the lights do not come on, you should take
the vehicle to your dealer for service. An indicator light
will flash while shifting. It will stay on when the shift is
completed. If for some reason the transfer case cannot
make a requested shift, it will return to the last chosen
setting.
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Shifting Into Four-Wheel Drive High or
AUTO (Automatic Four-Wheel Drive)
Turn the knob to the Four-Wheel High or AUTO
position. This can be done at any speed, except when
shifting from Four-Wheel Drive Low. The indicator light
will flash while shifting. It will remain on when the shift is
completed.
Shifting Into Two-Wheel Drive High
Turn the knob to the Two-Wheel High position. This can
be done at any speed, except when shifting from
Four-Wheel Drive Low.
See shifting out of Four-Wheel Drive Low later in this
section for more information.
Shifting Into Four-Wheel Drive Low
When Four-Wheel Low is engaged, vehicle speed
should be kept below 45 mph (72 km/h). Extended
high-speed operation in 4L may damage or shorten
the life of the drivetrain.
To shift to the Four-Wheel Drive Low position, the
ignition must be in ON/RUN and the vehicle must be
stopped or moving less than 3 mph (5 km/h) with thetransmission in N (Neutral). The preferred method for
shifting into Four-Wheel Drive Low is to have the
vehicle moving 1 to 2 mph (1.6 to 3.2 km/h). Turn the
knob to the Four-Wheel Drive Low position. You must
wait for the Four-Wheel Drive Low indicator light to stop
flashing and remain on before shifting the transmission
into gear.
Notice:
Shifting the transmission into gear before
the Four-Wheel Drive Low indicator light has
stopped flashing could damage the transfer case.
To help avoid damaging the vehicle, always wait for
the Four-Wheel Drive Low indicator light to stop
flashing before shifting the transmission into gear.
The vehicle may have significant engagement noise
and bump when shifting between Four-Wheel Drive Low
and Four-Wheel Drive High ranges or from N (Neutral)
while the engine is running.
If the knob is turned to the Four-Wheel Drive Low
position when the vehicle is in gear and/or moving,
the Four-Wheel Drive Low indicator light will flash
for 30 seconds and not complete the shift unless the
vehicle is moving less than 3 mph (5 km/h) and the
transmission is in N (Neutral). After 30 seconds the
transfer case will shift to Four-Wheel Drive High mode.
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Shifting Out of Four-Wheel Drive Low
To shift from Four-Wheel Drive Low to Four-Wheel Drive
High, AUTO, or Two-Wheel Drive High, the vehicle must
be stopped or moving less than 3 mph (5 km/h) with the
transmission in N (Neutral) and the ignition in ON/RUN.
The preferred method for shifting out of Four-Wheel
Drive Low is to have your vehicle moving 1 to 2 mph
(1.6 to 3.2 km/h). Turn the knob to the Four-Wheel
Drive High, AUTO, or Two-Wheel Drive High position.
You must wait for the Four-Wheel Drive High, AUTO,
or Two-Wheel Drive High indicator light to stop flashing
and remain on before shifting the transmission
into gear.
Notice:Shifting the transmission into gear before
the Four-Wheel Drive Low indicator light has
stopped flashing could damage the transfer case.
To help avoid damaging the vehicle, always wait for
the Four-Wheel Drive Low indicator light to stop
flashing before shifting the transmission into gear. The vehicle may have significant engagement noise
and bump when shifting between Four-Wheel Drive Low
and Four-Wheel Drive High ranges or from N (Neutral)
while the engine is running.
If the knob is turned to the Four-Wheel Drive High,
AUTO, or Two-Wheel Drive High switch position when
the vehicle is in gear and/or moving, the Four-Wheel
Drive High, AUTO or Two-Wheel Drive High indicator
light will flash for 30 seconds but will not complete the
shift unless the vehicle is moving less than 3 mph
(5 km/h) and the transmission is in N (Neutral).
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Shifting into Neutral
To shift the transfer case to N (Neutral) do the following:1. Make sure the vehicle is parked so that it will not roll.
2. Set the parking brake and apply the regular brake pedal. See Parking Brake
on page 3‑48for more
information.
3. Start the vehicle or turn the ignition to ON/RUN.
4. Put the transmission in N (Neutral).
5. Shift the transfer case to Two-Wheel Drive High.
6. Turn the transfer case dial clockwise to N (Neutral) until it stops and hold it there until the N (Neutral)
light starts blinking. This will take at least
10 seconds. Then slowly release the dial to the
Four‐Wheel Drive Low position. The N (Neutral)
light will come on when the transfer case shift to
N (Neutral) is complete.
7. If the engine is running, verify that the transfer case is in N (Neutral) by shifting the transmission
to R (Reverse) for one second, then shift the
transmission to D (Drive) for one second. 8. Turn the ignition to ACC/ACCESSORY, which will
turn the engine off.
9. Place the transmission shift lever in P (Park).
10. Release the parking brake prior to moving the vehicle.
11. Turn the ignition to LOCK/OFF.
Shifting Out of Neutral
To shift out of N Neutral do the following: 1. Set the parking brake and apply the regular brake pedal.
2. Turn the ignition to ON/RUN with the engine off, and shift the transmission to N (Neutral).
3. Turn the transfer case dial to the desired transfer case shift position (Two-Wheel Drive High,
Four-Wheel Drive High, AUTO).
After the transfer case has shifted out of
N (Neutral), the N (Neutral) light will go out.
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Automatic Transfer Case
The transfer case knob is
located to the left of the
instrument panel cluster.
Use this dial to shift into and out of four-wheel drive.
The vehicle has Four-Wheel-Drive with StabiliTrak
®.
For information on StabiliTrak®, see StabiliTrak®Systemon page 5‑6.
You can choose among three driving settings:
Indicator lights in the switch show you which setting you
are in. The indicator lights will come on briefly when you
turn on the ignition and the last chosen setting will stay
on. If the lights do not come on, you should take the
vehicle to your dealer for service. An indicator light will flash while shifting. It will stay on when the shift is
completed. If for some reason the transfer case cannot
make a requested shift, it will return to the last chosen
setting.
2
m(Two-Wheel Drive High):
This setting is used for
driving in most street and highway situations. The front
axle is not engaged in two-wheel drive. This setting also
provides the best fuel economy.
AUTO (Automatic Four-Wheel Drive): This setting is
ideal for use when road surface traction conditions are
variable. When driving the vehicle in AUTO, the front
axle is engaged, but the vehicle's power is primarily
sent to the rear wheels. When the vehicle's software
determines a need for more traction, the system will
transfer more power to the front wheels. Driving in
this mode results in slightly lower fuel economy than
Two-Wheel Drive High.
4
m(Four-Wheel Drive High): Use the four-wheel
high position when you need extra traction, such as
on snowy or icy roads or in most off-road situations.
This setting also engages the front axle to help drive
the vehicle. This is the best setting to use when
plowing snow.
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Service Four Wheel Drive
If the SERVICE 4 WHEEL DRIVE message stays on,
you should take the vehicle to your dealer for service.
See“SERVICE 4 WHEEL DRIVE message” underDIC
Warnings and Messages on page 4‑61.
Shifting Into Four-Wheel Drive High or
AUTO (Automatic Four-Wheel Drive)
Turn the knob to the Four-Wheel High or AUTO
position. This can be done at any speed. The indicator
light will flash while shifting. It will remain on when the
shift is completed.
Shifting Into Two-Wheel Drive High
Turn the knob to the Two-Wheel High position. This can
be done at any speed. The indicator light will flash while
shifting. It will remain on when the shift is completed.
Excessively shifting the transfer case into or out of the
different modes may cause the transfer case to enter
the shift protection mode. This will protect the transfer
case from possible damage and will only allow the
transfer case to respond to one shift per 10 seconds.
The transfer case may stay in this mode for up to
three minutes.
Parking Brake
Set the parking brake by holding the regular brake
pedal down, then pushing down the parking brake
pedal.
If the ignition is on, the brake system warning light
will come on. See Brake System Warning Light
on
page 4‑36.
Notice: Driving with the parking brake on can
overheat the brake system and cause premature
wear or damage to brake system parts. Make sure
that the parking brake is fully released and the
brake warning light is off before driving.
3-48