2004 GMC SIERRA DENALI light

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.
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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Manual Operation
You may manually adjust the air delivery mode or fan
speed.
w9x(Fan):The switch with the fan symbol allows
you to manually adjust the fan speed. Press the up
arrow to increase fan speed and the down arrow
to decrease fan speed.
Pressing this button when the system is off will turn the
system on.
C(Mode):Press this button to manually change the
direction of the air¯ow in your vehicle; keep pressing the
button until the desired mode appears on the display.
If you press the mode button to select an air delivery
mode, the display will change to show you the selected
air mode delivery. The display will then show the
current status of the system. When the system is turned
off, the display will go blank after displaying the
current status of the system.
H(Panel):This setting will deliver air to the
instrument panel outlets.
)(Bi-Level):This setting will deliver warmer air to the
¯oor and cooler air to the instrument panel outlets.
6(Floor):This setting will deliver air to the ¯oor
outlets.
-(Defog):See ªDefogging and Defrostingº later in
this section.
@(Recirculation):Press this button to limit the
amount of outside air entering your vehicle. The light on
the recirculation button will glow. This is helpful when you
are trying to limit odors entering your vehicle and for
maximum air conditioning performance in hot weather.
Press this button again to allow outside air to enter the
vehicle. The light on the recirculation button will go off.
Pressing this button also cancels the auto recirculation
feature. To resume the auto recirculation function, press
the AUTO button. Each time the vehicle is started, the
system will revert to the auto recirculation function.
If you select recirculation while in defrost, defog or ¯oor,
the light in the button will ¯ash and then go out to let you
know that this is not allowed. This is normal and helps to
prevent fogging.
When the weather is cool or damp, operating the system
in recirculation for extended periods of time may cause
fogging of the vehicle's windows. To clear the fog, select
either defog or front defrost.
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Defogging and Defrosting
You can use either defog or front defrost to clear fog or
frost from your windshield. Use the defog mode to
clear the windows of fog or moisture. Use the front
defrost button to defrost the front windshield.
-(Defog):Use this setting to clear the windows of fog
or moisture. Press the mode button to select this
setting. This setting will deliver air to the ¯oor and
windshield outlets.
0(Front Defrost):Press the front defrost button to
defrost the windshield. The system will automatically
control the fan speed if you select defrost from AUTO
mode. If the outside temperature is 40ÉF (4ÉC) or
warmer, your air conditioning compressor will
automatically run to help dehumidify the air and dry the
windshield.
Rear Window Defogger
If your vehicle has this feature, the lines you see on the
rear window warm the glass. The rear window
defogger uses a warming grid to remove fog from the
rear window.
<(Rear):Press this button to turn the rear window
defogger on or off. An indicator light in the button
will come on to let you know that the rear window
defogger is activated.
The rear window defogger will turn off about 10 minutes
after the button is pressed. If you need additional
warming time, press the button again.
If your vehicle is equipped with heated mirrors this
button will activate them.
Notice:Using a razor blade or sharp object to clear
the inside rear window may damage the rear
window defogger. Repairs would not be covered by
your warranty. Do not clear the inside of the rear
window with sharp objects.
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Warning Lights, Gages and
Indicators
Warning Lights, Gages, and
Indicators
This part describes the warning lights and gages that
may be on your vehicle. The pictures will help you
locate them.
Warning lights and gages can signal that something is
wrong before it becomes serious enough to cause
an expensive repair or replacement. Paying attention to
your warning lights and gages could also save you
or others from injury.
Warning lights come on when there may be or is a
problem with one of your vehicle's functions. As you will
see in the details on the next few pages, some
warning lights come on brie¯y when you start the
engine just to let you know they're working. If you are
familiar with this section, you should not be alarmed
when this happens.Gages can indicate when there may be or is a problem
with one of your vehicle's functions. Often gages
and warning lights work together to let you know when
there's a problem with your vehicle.
When one of the warning lights comes on and stays on
when you are driving, or when one of the gages
shows there may be a problem, check the section that
tells you what to do about it. Please follow this
manual's advice. Waiting to do repairs can be
costly ± and even dangerous. So please get to know
your warning lights and gages. They're a big help.
Your vehicle also has a driver information system that
works along with the warning lights and gages. See
Driver Information Center (DIC) on page 3-46.
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Speedometer and Odometer
Your speedometer lets you see your speed in both
miles per hour (mph) and kilometers per hour (km/h).
Your odometer shows how far your vehicle has
been driven, in either miles (used in the United States)
or kilometers (used in Canada).
Trip Odometer
The trip odometer can tell you how far your vehicle
has been driven since you last set the trip odometer
to zero.
Press the reset button, located on the instrument panel
cluster next to the trip odometer display, to toggle
between the trip odometer and the regular odometer.
Holding the reset button for approximately one second
while the trip odometer is displayed will reset it.
To display the odometer reading with the ignition off,
press the reset button.
Engine Hour Meter Display
The odometer can also display the number of hours the
engine has run. To display the hour meter, turn the
ignition off, press and hold the reset button for at least
four seconds. The hour meter will be displayed for
up to 30 seconds, or until the ignition is turned on.
Tachometer
Your tachometer displays the engine speed in
revolutions per minute (rpm).
Notice:If you operate the engine with the
tachometer in the shaded warning area, your vehicle
could be damaged, and the damages would not
be covered by your warranty. Do not operate
the engine with the tachometer in the shaded
warning area.
Safety Belt Reminder Light
When the key is turned to RUN or START, a chime will
come on for several seconds to remind people to
fasten their safety belts, unless the driver's safety belt is
already buckled.
The safety belt light will
also come on and stay
on for several seconds,
then it will ¯ash for
several more.
If the driver's belt is already buckled, neither the chime
nor the light will come on.
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Air Bag Readiness Light
There is an air bag readiness light on the instrument
panel cluster, which shows the air bag symbol.
The system checks the air bag's electrical system for
malfunctions. The light tells you if there is an electrical
problem. The system check includes the air bag
sensors, the air bag modules, the passenger sensing
system (if equipped), the wiring and the crash sensing
and diagnostic module. For more information on the
air bag system, see
Air Bag Systems on page 1-62.
This light will come on
when you start your
vehicle, and it will ¯ash for
a few seconds. Then
the light should go out.
This means the system
is ready.
If the air bag readiness light stays on after you start the
vehicle or comes on when you are driving, your air
bag system may not work properly. Have your vehicle
serviced right away.
Air Bag Off Light
When you turn the right front passenger's air bag off,
this light will be lit and stay lit to remind you that the air
bag has been turned off. This light will go off when
you turn the air bag back on again. See
Air Bag
Off Switch on page 1-68for more on this, including
important safety information.The AIR BAG OFF light will
look like one of the following illustrations.
United States with Passenger Sensing System
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{CAUTION:
If the air bag readiness light ever comes on
when you have turned off the air bag, it means
that something may be wrong with the air bag
system. The right front passenger's air bag
could in¯ate even though the switch is off. If
this ever happens, don't let anyone whom the
national government has identi®ed as a
member of a passenger air bag risk group sit
in the right front passenger's position (for
example, don't secure a rear-facing child
restraint in your vehicle) until you have your
vehicle serviced.
Passenger Air Bag Status Indicator
If your vehicle has the passenger sensing system
your rearview mirror will have a passenger air bag status
indicator.
When the ignition key is turned to RUN or START, the
passenger air bag status indicator will light ON and
OFF, or the symbol for on and off, for several seconds
as a system check.Passenger Air Bag Status Indicator ± United States
Passenger Air Bag
Status Indicator
± Canada
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Then, after several more seconds, the status indicator
will light either ON or OFF, or either the on or off symbol
to let you know the status of the right front passenger's
frontal air bag.
If the word ON or the on symbol is lit on the passenger
air bag status indicator, it means that the right front
passenger's frontal air bag is enabled (may in¯ate).
{CAUTION:
If the on indicator comes on when you have a
rear-facing child restraint installed in the right
front passenger's seat, it means that the
passenger sensing system has not turned off
the passenger's frontal air bag. A child in a
rear-facing child restraint can be seriously
injured or killed if the right front passenger's
air bag in¯ates. This is because the back of
the rear-facing child restraint would be very
close to the in¯ating air bag. Don't use a
rear-facing child restraint in the right front
passenger's seat unless the air bag has been
turned off.If the word OFF or the off symbol is lit on the passenger
air bag status indicator, it means that the passenger
sensing system or the air bag off switch has turned off
the right front passenger's air bag. See
Passenger
Sensing System on page 1-73orAir Bag Off Switch on
page 1-68for more on this, including important safety
information.
{CAUTION:
If the right front passenger's air bag is turned
off for a person who isn't in a risk group
identi®ed by the national government, that
person won't have the extra protection of an
air bag. In a crash, the air bag wouldn't be able
to in¯ate and help protect the person sitting
there. Don't turn off the passenger's air bag
unless the person sitting there is in a risk
group. See²Air Bag Off Switch²in the Index
for more on this, including important safety
information.
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