2005 GMC YUKON ac system

The three modes you can choose between are:
d(StabiliTrak®):This button is used to enable or
disable the StabiliTrak®and is also used to shift the
transfer case into Neutral (N). For more information on
using StabiliTrak
®, seeStabiliTrak®System on
page 4-10.
f(All-Wheel Drive):This button allows the transfer
case to distribute power to all four wheels as needed
depending on road and driving conditions.
4
n(4LO):This button allows the transfer case to
deliver extra torque to the wheels, and provides for
precise control of wheel speed by engine braking. You
may never need this setting. It sends maximum power to
all four wheels. You might choose four-wheel low if you
are driving off-road in deep sand, deep mud, deep snow,
and while climbing or descending steep hills.
{CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the
transmission is in PARK (P). You or someone
else could be seriously injured. Be sure to set
the parking brake before placing the transfer
case in NEUTRAL. SeeParking Brake on
page 2-35.
N (Neutral):Shift the vehicle’s transfer case to
NEUTRAL only when towing your vehicle. See
Recreational Vehicle Towing on page 4-62orTowing
Your Vehicle on page 4-62for more information.
Indicator lights in the buttons show which mode you are
in. The indicator lights will come on briey when you
turn on the ignition and one will stay on. If the lights do
not come on, you should take your vehicle to your
dealer for service. An indicator light will ash while the
transfer case is shifting. It will remain on when the
shift is complete. If for some reason the transfer case
cannot make a requested shift, it will return to the
last chosen setting.
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If the SERVICE 4WD message stays on, you should
take your vehicle to your dealer for service. See
SERVICE 4WD underDriver Information Center (DIC)
on page 3-54.
Shifting Into Four Wheel Low
To shift to the Four-Wheel Low position, the ignition
must be in RUN and the vehicle must be stopped
or moving less than 3 mph (5 km/h) with the
transmission in NEUTRAL (N). Press and release the
Four-Wheel Low switch. You must wait for the
Four-Wheel Low indicator light to stop ashing and
remain on before shifting your transmission in gear.
Notice:Shifting the transmission into gear before
the Four-Wheel Low indicator light has stopped
ashing could damage the transfer case. To
help avoid damaging your vehicle, always wait for
the Four-Wheel Low indicator light to stop ashing
before shifting the transmission into gear.
If the Four-Wheel Low button is pressed when your
vehicle is in gear and/or moving, the Four-Wheel Low
indicator light will ash for 30 seconds and not complete
the shift unless your vehicle is moving less than
3 mph (5 km/h) and the transmission is in NEUTRAL (N).
After 30 seconds, the transfer case will return to the
setting last chosen.
When in Four-Wheel Low, StabiliTrak
®is automatically
disabled. For more information seeStabiliTrak®
System on page 4-10.
Shifting Out of Four Wheel-Low
To shift from Four-Wheel Low to All-Wheel Drive, your
vehicle must be stopped or moving less than 3 mph
(5 km/h) with the transmission in NEUTRAL (N) and the
ignition in RUN. Press and release the all-wheel drive
button. You must wait for the All-Wheel Drive indicator
light to stop ashing and remain illuminated before
shifting your transmission into gear.
If the All-Wheel Drive button is pressed when your
vehicle is in gear and/or moving, the All-Wheel Drive
indicator light will ash for 30 seconds but will not
complete the shift unless your vehicle is moving less
than 3 mph (5 km/h) and the transmission is in
NEUTRAL (N).
Shifting Into NEUTRAL
To shift the transfer case to NEUTRAL, do the following:
1. Make sure the vehicle is parked so that it will
not roll.
2. Set the parking brake. SeeParking Brake on
page 2-35for more information.
3. Start the vehicle or turn the ignition to RUN.
4. Put the transmission in NEUTRAL (N).
5. Shift the transfer case to All-Wheel Drive.
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Parking Brake
To set the parking brake, hold the regular brake pedal
down with your right foot. Push down the parking
brake pedal with your left foot.
A chime will activate and the warning light will ash
when the parking brake is applied and the vehicle
is moving at least 3 mph (5 km/h) for at least
three seconds.To release the parking brake, hold the regular brake
pedal down. Pull the bottom edge of the lever, located
above the parking brake pedal, with the parking
brake symbol, to release the parking brake.
If the ignition is on when the parking brake is released,
the brake system warning light will go off.
Notice:Driving with the parking brake on can
overheat the brake system and cause premature
wear or damage to brake system parts. Verify that
the parking brake is fully released and the brake
warning light is off before driving.
If you are towing a trailer and are parking on any hill,
seeTowing a Trailer on page 4-67.
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Shifting Out of Park (P)
Automatic Transmission
Your vehicle has an automatic transmission shift lock
control system which locks the shift lever in PARK (P)
when the ignition is in the LOCK position. You have
to fully apply your regular brakes before you can shift
from PARK (P) when the ignition is in RUN. See
Automatic Transmission Operation on page 2-23.
If you cannot shift out of PARK (P), ease pressure on
the shift lever and push the shift lever all the way up into
PARK (P) as you maintain brake application. Then,
move the shift lever into the gear you want.If you ever hold the brake pedal down but still can’t shift
out of PARK (P), try this:
1. Turn the key to ACCESSORY. There is no shift
interlock in this key position.
2. Apply and hold the brake until the end of Step 4.
3. Shift the transmission to NEUTRAL (N).
4. Start the vehicle and then shift to the gear
you want.
5. Have the system xed as soon as you can.
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Parking Over Things That Burn
{CAUTION:
Things that can burn could touch hot exhaust
parts under your vehicle and ignite. Do not
park over papers, leaves, dry grass or other
things that can burn.
Engine Exhaust
{CAUTION:
Engine exhaust can kill. It contains the gas
carbon monoxide (CO), which you cannot see
or smell. It can cause unconsciousness and
death.
You might have exhaust coming in if:
Your exhaust system sounds strange or
different.
Your vehicle gets rusty underneath.
Your vehicle was damaged in a collision.
Your vehicle was damaged when driving
over high points on the road or over road
debris.
Repairs were not done correctly.
Your vehicle or exhaust system had been
modied improperly.
If you ever suspect exhaust is coming into
your vehicle:
Drive it only with all the windows down to
blow out any CO; and
Have your vehicle xed immediately.
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Running the Engine While Parked
It is better not to park with the engine running. But if you
ever have to, here are some things to know.
{CAUTION:
Idling the engine with the climate control
system off could allow dangerous exhaust into
your vehicle. See the earlier caution under
Engine Exhaust on page 2-39.
Also, idling in a closed-in place can let deadly
carbon monoxide (CO) into your vehicle even if
the climate control fan is at the highest setting.
One place this can happen is a garage.
Exhaust — with CO — can come in easily.
NEVER park in a garage with the engine
running.
Another closed-in place can be a blizzard. See
Winter Driving on page 4-45.
{CAUTION:
It can be dangerous to get out of your vehicle
if the shift lever is not fully in PARK (P) with
the parking brake rmly set. Your vehicle can
roll. Do not leave your vehicle when the engine
is running unless you have to. If you have left
the engine running, the vehicle can move
suddenly. You or others could be injured. To
be sure your vehicle will not move, even when
you are on fairly level ground, always set your
parking brake and move the shift lever to
PARK (P).
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{CAUTION:
Four-wheel drive vehicles with the transfer
case in NEUTRAL will allow the vehicle to roll,
even if your shift lever is in PARK (P). So, be
sure the transfer case is in a drive gear — not
in NEUTRAL. Always set your parking brake.
Follow the proper steps to be sure your vehicle will not
move. SeeShifting Into Park (P) on page 2-36.
If you are pulling a trailer, seeTowing a Trailer on
page 4-67.
Mirrors
Manual Rearview Mirror
Pull the tab under the mirror toward you to reduce glare
from headlamps behind you after dark. Push the tab
away from you for normal daytime operation.
Automatic Dimming Rearview Mirror
with OnStar
®, Compass and
Temperature Display
Your vehicle may have this feature. When on, the
automatic dimming mirror dims to the proper level to
minimize glare from lights behind you after dark.
The mirror has a dual display in the upper right corner
of the mirror face that shows the compass reading
and the outside temperature.
Control buttons for the OnStar
®system are at the
bottom of the mirror. SeeOnStar®System on page 2-50
for more information about the services OnStar®
provides.
P(On/Off):This is the on/off button.
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Passenger Airbag Indicator
The vehicle may be equipped with a passenger airbag
indicator, on the mirror glass, just above the buttons.
For more information, seePassenger Sensing System
on page 1-75andPassenger Airbag Status Indicator
on page 3-40.
Cleaning the Mirror
When cleaning the mirror, use a paper towel or similar
material dampened with glass cleaner. Do not spray
glass cleaner directly on the mirror as that may cause
the liquid cleaner to enter the mirror housing.
Automatic Dimming Rearview Mirror
with Compass and Temperature
Display
Your vehicle may be equipped with this feature. When
on, an automatic dimming mirror will dim to the
proper level to minimize glare from lights behind you
after dark.
The mirror also includes a dual display in the upper
right corner of the mirror with the compass reading and
the outside temperature. The display can be turned
on or off by briey pressing either the TEMP or
the COMP button.
Temperature Display
The temperature can be displayed by pressing the
TEMP button. Pressing the TEMP button once briey,
will toggle the temperature reading on and off. To
alternate the temperature reading between Fahrenheit
and Celsius, press and hold the TEMP button for
approximately four seconds until the display blinks F
and C. Press and release the TEMP button to toggle
between the Fahrenheit and Celsius readings. After
approximately four seconds of inactivity, the display will
stop blinking and display the last selection made.
Press and release the TEMP button to toggle the
temperature display between Fahrenheit or Celsius.
If an abnormal reading is displayed, please consult your
GM dealer.
Automatic Dimming Mirror Operation
Press and hold the TEMP button for approximately eight
seconds to turn the automatic dimming feature on or
off. The indicator light to the left of the TEMP button will
turn on or off to indicate when the feature is on. Once
the mirror is turned off, it will remain off until it is turned
back on, or until the vehicle is restarted.
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