2005 GMC YUKON XL cooling system

Liftgate/Liftglass
{CAUTION:
It can be dangerous to drive with the liftgate or
liftglass open because carbon monoxide (CO)
gas can come into your vehicle. You cannot
see or smell CO. It can cause
unconsciousness and even death. If you must
drive with the liftgate open or if electrical
wiring or other cable connections must pass
through the seal between the body and the
liftgate or liftglass:
Make sure all other windows are shut.
Turn the fan on your heating or cooling
system to its highest speed and select the
control setting that will force outside air
into your vehicle. See Climate Control
System in the Index.
If you have air outlets on or under the
instrument panel, open them all the way.
SeeEngine Exhaust on page 2-30.To unlock the liftgate and liftgate glass from the outside
use either the power door locks or the remote keyless
entry system.
The liftgate glass can be opened using the pushbutton
on the liftgate after the doors have been unlocked.
To open the entire liftgate, lift the handle located in the
center of the door.
To lock the liftgate and liftgate glass from the outside
use the remote keyless entry system or the power
door locks.
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Ashtrays and Cigarette Lighter
The front ashtray and lighter are located in the center
console near the cupholders. Press on the access door
to open it and use the ashtray and lighter.
Notice:If you put papers or other ammable items
in the ashtray, hot cigarettes or other smoking
materials could ignite them and possibly damage
your vehicle. Never put ammable items in the
ashtray.
To remove the ashtray, pull it from the center console.
Slide it back in and push down to be sure it is secure.
To use the cigarette lighter, push it in all the way, and let
go. When it’s ready, it will pop back out by itself.
Notice:Holding a cigarette lighter in while it is
heating will not allow the lighter to back away from
the heating element when it is hot. Damage from
overheating may occur to the lighter or heating
element, or a fuse could be blown. Do not hold a
cigarette lighter in while it is heating. Do not
use anything other than the cigarette lighter in the
heating element.
Climate Controls
Dual Automatic Climate Control
System
With this system, you can control the heating, cooling
and ventilation in your vehicle.
You can select different climate control settings for the
driver and passengers.
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If the driver’s and passenger’s temperature settings
are not the same, the opposite side temperature
setting will be displayed for an additional
ve seconds. To make the passenger’s temperature
the same as the driver’s press and hold the
AUTO button for about four seconds.
When auto is selected, the air conditioning operation
and air inlet will be automatically controlled. The
air conditioning compressor will run when the
outside temperature is over about 40°F (4°C). The
air inlet will normally be set to outside air. If it’s
hot outside, the air inlet may automatically switch to
recirculate inside air to help quickly cool down
your vehicle. The light on the button will illuminate
in recirculation.
2. Set the driver’s and passenger’s temperature.
To nd your comfort setting, start with a 74°F (23°C)
temperature setting and allow about 20 minutes
for the system to regulate. Turn the driver’s or
passenger’s side temperature knob to adjust the
temperature setting as necessary. If you choose the
temperature setting of 60°F (15°C) the system
will remain at the maximum cooling setting. If you
choose the temperature setting of 90°F (32°C)
the system will remain at the maximum heat setting.
Choosing either maximum setting will not cause
the vehicle to heat or cool any faster.Be careful not to cover the sensor located on the
top of the instrument panel near the windshield. This
sensor regulates air temperature based on sun
load, and also turns on your headlamps.
To avoid blowing cold air in cold weather, the
system will delay turning on the fan until warm air is
available. The length of delay depends on the
engine coolant temperature. Pressing the fan switch
will override this delay and change the fan to a
selected speed.
9(Off):Press this button to turn off the entire climate
control system. Outside air will still enter the vehicle, and
will be directed to the oor. This direction can be changed
by pressing the mode button. The temperature can also
be adjusted using either temperature knob. Press the up
or down arrows on the fan switch, the defrost button, the
AUTO button, or the air conditioning button to turn the
system on when it is off.
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Rear Passenger Console Control
To use the rear climate control from the rear passenger
position, use the rear passenger console control. The
driver overhead control fan knob must be set to the
AUX position.
The rear seat controls have the following settings:
O(On/Off):Press this button to turn the rear seat
comfort controls on or off when the front overhead
control is set to AUX.
%(Mode):Press this button to select the air delivery
mode and AUTO mode. Choose AUTO if you want
the system to automatically regulate the airow.
See “Auto Mode” later in this section for more
information on using this feature.
b(Temperature):Press this button up or down to
increase or decrease the temperature setting.
w9x(Fan):Press this button up or down to adjust
the fan speed. Choose AUTO if you want the system
to automatically choose the fan speed to maintain
a selected temperature. See “Auto Mode” later in this
section for more information on using this feature.
AUTO Mode
When using the system in auto mode, nd your comfort
setting by placing the temperature control to 74°F (23°C)
and allowing about 20 minutes for the system to regulate.
Then adjust the temperature setting as necessary. If you
choose full cold 60°F (15°C), the system will remain at
the maximum cooling setting. If you choose full hot
90°F (32°C), the system will remain at the maximum
heat setting. Rear Controls
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Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
It also provides an indicator of how hard your vehicle is
working. During a majority of the operation, the gage
will read 210°F (100°C) or less. If you are pulling a load
or going up hills, it is normal for the temperature to
uctuate and approach the 250°F (122°C) mark. If the
gage reaches the 260°F (125°C) mark, it indicates
that the cooling system is working beyond its capacity.
SeeEngine Overheating on page 5-28.
Transmission Temperature Gage
Your vehicle may be equipped with a transmission
temperature gage.
When your ignition is on, the gage shows the
temperature of the transmission uid. The normal
operating range is from 180°F (82°C) to about
200°F (93°C). United States
CanadaUnited StatesCanada
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ENGINE COOLANT HOT
If the cooling system temperature gets hot, this message
will appear in the DIC. Stop the vehicle and let the engine
idle in PARK (P) to allow the coolant to reach a safe
temperature. This message will clear when the coolant
temperature drops to a safe operating temperature.
ENGINE OVERHEATED
If the engine cooling system reaches unsafe
temperatures for operation, this message will appear in
the DIC and you will hear a chime. Stop and turn off
the vehicle as soon as it is safe to do so to avoid severe
damage. This message will clear when the engine
has cooled to a safe operating temperature.
Notice:If you drive your vehicle while the engine is
overheating, severe engine damage may occur. If
an overheat warning appears on the instrument
panel cluster and/or DIC, stop the vehicle as soon
as possible. Do not increase the engine speed above
normal idling speed. SeeEngine Overheating on
page 5-28for more information.
FUEL LEVEL LOW
If the fuel level is low, this message will appear on the
DIC and you will hear a chime. Refuel as soon as
possible. Pressing any of the four DIC buttons, if
equipped, will clear the message from the DIC display.
If your vehicle is not equipped with the four DIC
buttons, pressing the trip odometer reset stem will clear
the message from the DIC display. It will also clear
itself after 10 seconds until the next ignition cycle. The
low fuel light near the fuel gage will still remain on
in either case. SeeFuel Gage on page 3-45,Fuel on
page 5-5andLow Fuel Warning Light on page 3-45.
KEYFOB X BATTERY LOW
If a remote keyless entry transmitter battery is low, this
message will appear on the DIC. The battery needs
to be replaced in the transmitter. See “Battery
Replacement” underRemote Keyless Entry System
Operation on page 2-6. Pressing any of the four
DIC buttons, if equipped, will clear the message from
the DIC display. If your vehicle is not equipped with the
four DIC buttons, pressing the trip odometer reset
stem will clear the message from the DIC display.
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LEFT REAR DOOR AJAR
If the driver’s side rear door is not fully closed and the
vehicle is in a drive gear, this message will appear
on the display and you will hear a chime. Stop and turn
off the vehicle, check the door for obstacles and
close the door again. Check to see if the message still
appears on the DIC. Pressing any of the four DIC
buttons, if equipped, will clear the message from the
DIC display. If your vehicle is not equipped with the four
DIC buttons, pressing the trip odometer reset stem
will clear the message from the DIC display.
LOW COOLANT LEVEL
If your vehicle is equipped with low coolant level sensor,
this message will appear on the DIC if the engine coolant
level is low. Adding coolant will clear the message. See
Cooling System on page 5-30. Pressing any of the four
DIC buttons, if equipped, will acknowledge the message
and clear it from the DIC display. If your vehicle is not
equipped with the four DIC buttons, pressing the trip
odometer reset stem will acknowledge the message and
clear it from the DIC display.
Notice:Engine damage from running your engine
without coolant is not covered by your warranty. See
“Overheated Engine Protection Operating Mode”
in the Index for information on driving to a safe
place in an emergency.
OIL LIFE RESET
This message will appear on the display for about
10 seconds after resetting the change engine oil
message. See “Engine Oil Life System” underDIC
Operation and Displays on page 3-47andEngine Oil on
page 5-14for more information.
OIL PRESSURE LOW
If low oil pressure levels occur, this message will be
displayed on the DIC and a chime will sound. Stop the
vehicle as soon as safely possible and do not operate
it until the cause of the low oil pressure has been
corrected. Check your oil as soon as possible and have
your vehicle serviced by your GM dealer. SeeEngine
Oil on page 5-14.
Notice:If you drive your vehicle while the engine
oil pressure is low, severe engine damage may
occur. If a low oil pressure warning appears on the
Driver Information Center (DIC), stop the vehicle
as soon as possible. Do not drive the vehicle until
the cause of the low oil pressure is corrected.
SeeEngine Oil on page 5-14for more information.
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PASSENGER DOOR AJAR
If the passenger’s door is not fully closed and the
vehicle is in a drive gear, this message will appear on
the display and you will hear a chime. Stop and turn off
the vehicle, check the door for obstacles and close
the door again. Check to see if the message still
appears on the DIC. Pressing any of the four DIC
buttons, if equipped, will clear the message from the DIC
display. If your vehicle is not equipped with the four
DIC buttons, pressing the trip odometer reset stem will
clear the message from the DIC display.
REAR ACCESS OPEN
If the liftgate is open while the ignition is in RUN, this
message will appear on the DIC and you will hear
a chime. Turn off the vehicle and check the liftgate.
Restart the vehicle and check for the message on the
DIC display. Pressing any of the four DIC buttons,
if equipped, will clear the message from the DIC display.
If your vehicle is not equipped with the four DIC
buttons, pressing the trip odometer reset stem will clear
the message from the DIC display.
REDUCED ENGINE POWER
This message is displayed and you will hear a chime
when the cooling system temperature gets too hot and
the engine further enters the engine coolant protection
mode. SeeEngine Overheating on page 5-28for further
information.
REPLACE LIFTGATE FUSE
This message will be displayed if the liftgate lock
malfunctions and/or the liftgate fuse blows. For more
information on fuses, seeFuses and Circuit Breakers on
page 5-105. If the message returns after replacing the
fuse, see your GM dealer for service.
RIGHT REAR DOOR AJAR
If the passenger’s side rear door is not fully closed and
the vehicle is in a drive gear, this message will
appear on the display and you will hear a chime. Stop
and turn off the vehicle, check the door for obstacles and
close the door again. Check to see if the message
still appears on the DIC. Pressing any of the four DIC
buttons, if equipped, will clear the message from the DIC
display. If your vehicle is not equipped with the four
DIC buttons, pressing the trip odometer reset stem will
clear the message from the DIC display.
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