2004 CHEVROLET SILVERADO heating

DRIVE (D):This position is for normal driving. If you
need more power for passing, and you’re:
Going less than about 35 mph (55 km/h), push your
accelerator pedal about halfway down.
Going about 35 mph (55 km/h) or more, push the
accelerator all the way down.
You’ll shift down to the next gear and have more power.
Drive (D) can be used when towing a trailer, carrying
a heavy load, driving on steep hills or for off-road driving.
You may want to shift the transmission to THIRD (3)
or, if necessary, a lower gear selection if the
transmission shifts too often.
Notice:Extended idling for more than ve minutes
in DRIVE (D) on vehicles equipped with the Allison
Transmission may cause transmission overheating
and damage. Always put the gearshift lever in
PARK (P) if idle time is longer than ve minutes.
If your vehicle is equipped with the Allison
®
Transmission, it will initially attain rst range when
DRIVE (D) is selected. As vehicle speed increases, the
transmission will upshift automatically through each
available range up to FIFTH (5). As the vehicle slows,
the transmission will downshift automatically.
THIRD (3):This position is also used for normal driving,
however it offers more power and lower fuel economy
than DRIVE (D).SECOND (2):This position gives you more power but
lower fuel economy. You can use SECOND (2) on
hills. It can help control your speed as you go down
steep mountain roads, but then you would also want to
use your brakes off and on.
If you manually select SECOND (2) in a light duty
automatic transmission, the transmission will drive in
second gear. You may use this feature for reducing the
speed of the rear wheels when you are trying to start
your vehicle from a stop on slippery road surfaces.
FIRST (1):This position gives you even more power
(but lower fuel economy) than SECOND (2). You
can use it on very steep hills, or in deep snow or mud.
If the selector lever is put in FIRST (1) while the
vehicle is moving forward, the transmission won’t shift
into rst gear until the vehicle is going slowly enough.
Notice:Spinning the tires or holding the vehicle in
one place on a hill using only the accelerator
pedal may damage the transmission. If you are
stuck, do not spin the tires. When stopping on a hill,
use the brakes to hold the vehicle in place.
On cold days, approximately 32°F (0°C) or colder, your
transmission is designed to shift differently until the
engine reaches normal operating temperature. This is
intended to improve heater performance.
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Ashtrays and Cigarette Lighter
Your vehicle may be equipped with a front ashtray
located near the center of the instrument panel. Pull on
the door to open it.
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 front ashtray, pull the ashtray toward
you. To replace the ashtray, place the ashtray on
the slides at the side of its location in the instrument
panel. 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.
Climate Controls
Climate Control System
Fan Knob
The fan knob on the left side of the control panel
adjusts the fan speed. To increase airow, turn the knob
clockwise. To decrease airow, turn it counterclockwise.
To turn the fan off, turn the knob to the off position.
9(Off):If the fan is 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 knob.
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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.To change the current mode, select one of the following:
H(Vent):This mode directs air to the instrument
panel vents.
)(Bi-Level):This mode directs half of the air to the
instrument panel vents; then directs most of the
remaining air to the oor vents. A little air is directed
toward the windshield and the side window vents. Cooler
air is directed to the upper vents and warmer air to
the oor vents.
6(Floor):This mode directs most of the air to the
oor vents with a little air directed to the windshield and
the side window vents.
h(Recirculation):The recirculation mode is used
to recirculate the air inside of your vehicle. Use this
mode to help prevent outside odors and/or dust
from entering your vehicle or to help cool the air inside
of your vehicle more quickly. Press this button to
turn the recirculation mode on or off. The light on the
recirculation button will illuminate. Recirculation cannot
be used in oor, blend or defrost modes. An indicator
on the button will light up, ash three times and turn off
when recirculation is selected in these modes.The
air-conditioning compressor will also come on when this
mode is activated. While in recirculation mode the
windows may fog when the weather is cold and damp.
To clear the fog, select either the blend or defrost
mode and increase fan speed.
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Operation Tips

Keep the hood and front air inlets free of ice, snow,
or any other obstruction (such as leaves). The
heater and defroster will work far better, reducing
the chance of fogging the inside of your windows.
Keep the air path under the front seats clear
of objects. This helps air to circulate throughout
your vehicle.
Adding outside equipment to the front of your
vehicle, such as hood-air deectors, etc., may affect
the performance of the heating and air conditioning
system. Check with your dealer before adding
equipment to the outside of your vehicle.
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.
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Air Conditioning
#
(Air Conditioning):Press this button to turn the
air conditioning (A/C) compressor on and off. The
snowake symbol will appear on the display when
the A/C is on.
Pressing this button when the outside temperature is
too cool for air conditioning will make the snowake
symbol ash three times and then turn off to let
you know the air conditioning mode is not available. If
the air conditioning is on and the outside temperature
drops below a temperature which is too cool for air
conditioning to be effective, the snowake symbol will
turn off to let you know the air conditioning mode
has been canceled.
^(Air Conditioning Off):On some vehicles, when
you turn the air conditioning off, this symbol will appear
on the display. If your vehicle does not have this
symbol, the snowake symbol will turn off to let you
know the air conditioning is off.
When air conditioning is selected or in AUTO mode, the
system will run the air conditioning automatically to cool
and dehumidify the air entering the vehicle. If you select
A/C off while in front defrost, defog or recirculation, the
A/C snowake symbol will turn off, but the A/C
compressor will still run to help prevent fogging.On hot days, open the windows long enough to let hot
inside air escape. This reduces the time it takes for
your vehicle to cool down. Then keep your windows
closed for the air conditioner to work its best.
On cool, but sunny days while using manual operation
of the automatic system, use bi-level to deliver warm
air to the oor and cooler air to the instrument
panel outlets. To warm or cool the air delivered, turn the
temperature knob to the desired setting.
In AUTO mode the system will cool and dehumidify the
air inside the vehicle. Also while in AUTO mode, the
system will maximize its performance by using
recirculation as necessary.
Heating
On cold days when using manual operation of the
automatic system, choose oor mode to deliver air to
the oor outlets. To warm or cool the air delivered, turn
the temperature knob to the desired setting.
If you want to use the automatic mode, press
AUTO and adjust the temperature by turning the
temperature knob.
The heater works best if you keep the windows closed
while using it.
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Outlet Adjustment
Use the air outlets located
in the center and on the
side of your instrument
panel to direct the airow.
Your vehicle has air outlets that allow you to adjust the
direction and amount of airow inside the vehicle.
Move the louvers up or down. Use the thumbwheel next
to or underneath the outlet to close the louvers. For
the most efficient airow and temperature control, keep
the outlet in the fully opened position.
Rear seat outlets can be used to adjust airow toward
either seating area, the oor or upward. Move the center
louvers up or down to direct the airow.
Operation Tips

Keep the hood and front air inlets free of ice, snow,
or any other obstruction (such as leaves). The
heater and defroster will work far better, reducing
the chance of fogging the inside of your windows.
Keep the air path under the front seats clear
of objects. This helps air to circulate throughout
your vehicle.
Adding outside equipment to the front of your
vehicle, such as hood-air deectors, etc., may affect
the performance of the heating and air conditioning
system. Check with your dealer before adding
equipment to the outside of your vehicle.
3-32

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 5-38.
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 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 260°F (127°C). United States
CanadaUnited StatesCanada
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LEFT REAR DOOR AJAR (Crew Cab)
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 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. SeeEngine Oil on page 5-20.
OIL LIFE RESET
This message will appear on the display for
about 10 seconds after resetting the change engine
oil message.
PASSENGER DOOR AJAR
If the passenger’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.
RANGE SHIFT INHIBITED
(Allison Transmission®Only)
If the transmission is unable to shift into a selected gear
this message will appear on the DIC. The electronic
shift position indicator on the instrument panel cluster
may blink when this occurs. To make the vehicle shift to
the requested gear you may have to shift back to
PARK (P) or NEUTRAL (N) and re-select the
desired gear.
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.
SeeEngine Overheating on page 5-38for
further information.
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