2004 GMC SIERRA cooling

Temperature Knob
The middle knob on the control panel lets you select the
temperature of the air ¯owing into the passenger
area. Turn the knob clockwise toward the red area for
warmer air. Turn the knob counterclockwise toward
the blue area for cooler air.
Mode Knob
The right knob on the control panel allows you to
choose the direction of air delivery.
H(Vent):This setting directs the air through the
instrument panel outlets.
)(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):Air¯ow 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.
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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 ªRecirculationº 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 ªRecirculationº 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 passenger will be displayed
under and to the right of the temperature setting.
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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
40ÉF (4ÉC). 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 74ÉF (23ÉC)
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 60ÉF (15ÉC) the system
will remain at the maximum cooling setting. If you
choose the temperature setting of 90ÉF (32ÉC)
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.
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It also provides an indicator of how hard your vehicle is
working. During a majority of the operation, the gage
will read 210ÉF (100ÉC) or less. If you are pulling a load
or going up hills, it is normal for the temperature to
¯uctuate and approach the 250ÉF (122ÉC) mark. If the
gage reaches the 260ÉF (125ÉC) mark, it indicates
that the cooling system is working beyond its capacity.
See
Engine Overheating on page 5-36.
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 100ÉF (38ÉC) to about
265ÉF (130ÉC).
At approximately 265ÉF (130ÉC), the driver information
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 260ÉF (127ÉC).
See
Driver Information Center (DIC) on page 3-55for
further information.
United States
Canada
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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. See ªEngine Oil,
When to Changeº under
Engine Oil on page 5-18.
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.
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.
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 the
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.
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REDUCED ENGINE POWER
This message is displayed when the cooling system
temperature gets too hot and the engine further enters
the engine coolant protection mode.
See
Engine Overheating on page 5-36for further
information.
RIGHT REAR DOOR AJAR (Crew Cab)
If the passenger'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.
SERVICE AIRBAG
If there is a problem with the air bag system, this
message will be displayed on the DIC. Have a quali®ed
technician inspect the system for problems. Press
the select button to acknowledge the message and clear
it from the DIC display.
SERVICE BRAKE SYSTEM
If there is a problem with the brake system, this
message will be displayed on the DIC. If this message
appears, stop as soon as possible and turn off the
vehicle. Restart the vehicle and check for the message
on the DIC display. If the message is still displayed,
or appears again when you begin driving, the brake
system needs service.
SERVICE BRAKE BOOSTER
If your vehicle has vaccum assist power brakes, this
message will be displayed on the DIC when there is a
problem with the Supplemental Brake Assist system.
If the message is displayed immediately after starting
the vehicle or the message appears while driving,
your Supplemental Brake Assist system needs service.
See
Brake System Warning Light on page 3-43.
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After Off-Road Driving
Remove any brush or debris that has collected on the
underbody, chassis or under the hood. These
accumulations can be a ®re hazard.
After operation in mud or sand, have the brake linings
cleaned and checked. These substances can cause
glazing and uneven braking. Check the body structure,
steering, suspension, wheels, tires and exhaust
system for damage. Also, check the fuel lines and
cooling system for any leakage.
Your vehicle will require more frequent service due to
off-road use. Refer to the Maintenance Schedule
for additional information.
Driving at Night
Night driving is more dangerous than day driving.
One reason is that some drivers are likely to be
impaired Ð by alcohol or drugs, with night vision
problems, or by fatigue.
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If you drive regularly in steep country, or if you are
planning to visit there, here are some tips that can make
your trips safer and more enjoyable. See
Off-Road
Driving with Your Four-Wheel-Drive Vehicle on
page 4-20
for information about driving off-road.
·Keep your vehicle in good shape. Check all ¯uid
levels and also the brakes, tires, cooling system
and transmission. These parts can work hard
on mountain roads.
·Know how to go down hills. The most important
thing to know is this: let your engine do some of
the slowing down. Shift to a lower gear when you go
down a steep or long hill.
{CAUTION:
If you do not shift down, your brakes could get
so hot that they would not work well. You
would then have poor braking or even none
going down a hill. You could crash. Shift down
to let your engine assist your brakes on a
steep downhill slope.
{CAUTION:
Coasting downhill in NEUTRAL (N) or with the
ignition off is dangerous. Your brakes will have
to do all the work of slowing down. They could
get so hot that they would not work well. You
would then have poor braking or even none
going down a hill. You could crash. Always
have your engine running and your vehicle in
gear when you go downhill.
·Know how to go uphill. You may want to shift down
to a lower gear. The lower gears help cool your
engine and transmission, and you can climb the hill
better.
·Stay in your own lane when driving on two-lane
roads in hills or mountains. Do not swing wide
or cut across the center of the road. Drive at speeds
that let you stay in your own lane.
·As you go over the top of a hill, be alert. There
could be something in your lane, like a stalled car or
an accident.
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