2004 GMC YUKON cooling

Lockout Protection
This feature protects you from locking your key in the
vehicle when the key is in the ignition and a door
is open.
If the power lock switch is pressed when a door is open
and the key is in the ignition, all of the doors will lock
and then the driver’s door will unlock.
Liftgate
{CAUTION:
It Can be dangerous to drive with the liftgate
glass, liftgate or rear doors open because
carbon monoxide (CO) gas can come into your
vehicle. You can not see or smell CO. It can
cause unconsciousness and even death.
CAUTION: (Continued)
CAUTION: (Continued)
If you must drive with the liftgate glass, liftgate
or rear doors open or if electrical wiring or
other cable connections must pass through
the seal between the body and the liftgate
glass, liftgate or rear doors:
Make sure all other windows are shut.
Turn the fan on your heating or cooling
system to its highest speed with the
setting on VENT or OUTSIDE AIR. That will
force outside air into your vehicle. See
Climate Control System on page 3-22.
If you have air outlets on or under the
instrument panel, open them all the way.
SeeEngine Exhaust on page 2-42.
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)(Bi-Level):Air is delivered through the oor outlets
as well as the instrument panel outlets. The ow can
be divided between vent and oor outlets depending
upon where the knob is placed between the settings.
6(Floor):This setting directs most of the air through
the oor outlets, and the rest of the air is divided
between the windshield defroster outlets and the side
window defroster outlets.
W(Defog):Airow is delivered through the oor
outlets, the windshield defroster outlets and the side
window defroster outlets. The air ow can be divided
between oor and defrost depending upon where
the knob is placed between the settings.
1(Defrost):This setting directs most air through the
windshield defroster outlets, side window defroster
outlets and some through the oor outlets.
Dual Climate Control System
With this system you can control the heating, cooling
and ventilation for your vehicle.
9(Fan):Turn the left knob clockwise or
counterclockwise to increase or decrease the fan speed.
Turn the knob to the off position to turn off the fan. If
the knob is in off outside air will still enter the vehicle,
and will be directed based on the position of the
mode knob. The temperature can also be adjusted
using the temperature levers.
Turn the right knob clockwise or counterclockwise to
direct the airow inside of your vehicle.
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Dual Automatic Climate Control
System
With this system, you can control the heating, cooling
and ventilation in your vehicle. Your vehicle also
has a ow-through ventilation system described later in
this section.
You can select different climate control settings for the
driver and passengers.
Driver’s Side Temperature Knob
The driver’s side knob is used to adjust the temperature
of the air coming through the system on the driver’s
side. The temperature can be adjusted even if the
system is turned off. This is possible since outside air
will always ow through the system as the vehicle
is moving forward unless it is set to recirculation mode.
See “Recirculation” later in this section.
Turn the knob counterclockwise or clockwise to lower or
increase the cabin temperature. The display will show
the temperature setting decreasing or increasing and an
arrow pointing to the driver will be displayed under
and to the left of the temperature setting.
Passenger’s Side Temperature Knob
The passenger’s side knob can be used to change the
temperature of the air coming through the system
on the passenger’s side of the vehicle. The temperature
can be adjusted even if the system is turned off. This
is possible since outside air will always ow through the
system as the vehicle is moving forward unless it is
set to recirculation mode. See “Recirculation” later in this
section.
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Turn the knob counterclockwise or clockwise to lower or
increase the cabin temperature. The display will show
the temperature setting decreasing or increasing and an
arrow pointing to the passenger will be displayed
under and to the right of the temperature setting.
The passenger’s temperature setting can be set to
match the driver’s temperature setting by pressing and
holding the AUTO button for four seconds. Both the
driver and passenger arrows will be displayed.
Automatic Operation
AUTO (Automatic):When automatic operation is
active the system will control the inside temperature, the
air delivery, and the fan speed.
Use the steps below to place the entire system in
automatic mode:
1. Press the AUTO button.
When AUTO is selected, the display will change to
show the current driver’s set temperature, delivery
mode and fan speed. Press the AUTO button again
within ve seconds to display the passenger’s set
temperature.If the driver 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.
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Rear Passenger Console Control
To control the rear climate control from the rear
passenger seat 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 5-29.
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 100°F (38°C) to about
265°F (130°C).
At approximately 265°F (130°C), the message center
will display a TRANSMISSION HOT message and
the transmission will enter a transmission protection
mode. When the transmission enters the protection
mode, you may notice a change in the transmission
shifting patterns. The transmission will return to normal
shifting patterns when the transmission uid temperature
falls below 260°F (127°C). United States
CanadaUnited StatesCanada
3-49

CHANGE ENGINE OIL
This message is displayed when the engine oil needs to
be changed.
When you change the engine oil, be sure to reset the
CHANGE ENGINE OIL message. This message
will clear itself after 10 seconds until the next ignition
cycle, or until the message is reset. SeeEngine
Oil, When to ChangeunderEngine Oil on page 5-16.
CHECK OIL LEVEL
If the oil level in the vehicle is low, this message will
appear on the DIC. Check the oil level and correct it as
necessary. You may need to let the vehicle cool or
warm up and cycle the ignition to be sure this message
will clear. The message will clear itself after 10
seconds, until the next ignition cycle. Once the problem
is corrected, press the select button to clear the
message from the DIC display.
CHECK TIRE PRESSURE
If a low tire pressure is detected in any of the vehicle’s
tires, this message will appear on the DIC, along
with a chime. Press the select button, or reset stem, to
acknowledge the message and clear it from the DIC
display. It will appear at each ignition cycle until the tires
are inated to the correct ination pressure.
CHECK WASHER FLUID
If the washer uid level is low, this message will appear
on the DIC. Press the select button to acknowledge
the message and clear it from the DIC display.
The message will clear itself after 10 seconds, or until
the next ignition cycle. Adding washer uid will clear the
message.
DRIVER DOOR AJAR
If the driver’s door is not fully closed, 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. Press the select
button to acknowledge the message and clear it from
the DIC display.
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 safe operating
temperature. To acknowledge this message press the
select button
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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. The message will clear when the engine has
cooled to a safe operating temperature.
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. Press the select button to acknowledge this
message and clear it from the DIC display.
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. Press the select button
to acknowledge the message and clear it from the
DIC display.
LEFT REAR DOOR AJAR
If the driver’s side rear door is not fully closed, 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. Press the
select button to acknowledge the message and clear it
from the DIC display.
LOW COOLANT LEVEL
If your vehicle is equipped with a low coolant level
sensor, this message will appear on the DIC if
the engine coolant level is low. Adding coolant will clear
the message.
OIL LIFE RESET
This message will appear on the DIC display for about 10
seconds after the change engine oil message is reset.
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.
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