2003 GMC SIERRA DENALI Owners Manual

2. Set the driver’s and passenger’s temperature.
To find 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.
Manual Operation
To change the current setting, select one of the
following:
A 8f? v (Fan): This button allows you to manually
adjust the fan speed. Press the up arrow
to increase fan
speed and the down arrow
to decrease fan speed.
4d (Mode): Press this button to manually change the
direction of the airflow 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.
f;’ (Vent): This mode directs air to the instrument
panel vents.
+2 (Bi-Level): This mode directs half of the air to the
instrument panel vents, then directs the remaining air
to
the floor 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 floor
vents.
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(ri (Floor): This mode directs most of the air to the
floor vents. Some air also comes out of the defroster and
side window vents. Use this mode to send air to the
rear of the vehicle. Keep the area under the front seats
free of objects that could obstruct airflow to the rear
of the vehicle. The recirculation button cannot be
selected in the floor mode.
(Recirculation): Press this button to turn the
recirculation mode on or
off. The recirculation mode is
used to limit the amount of outside air entering your
vehicle. This is helpful when you are trying to prevent
outside odors and/or dust from entering your vehicle, or
to help cool the air inside of your vehicle more quickly.
When this mode is on, inside air will recirculate
throughout your vehicle. When this button is pressed,
an indicator light in the button will also come on to
let you know that it is activated.
If you select recirculation while in defrost, defog, or
floor, the light on the button will flash and go out to let
you know this is not allowed. This is to prevent
windshield fogging.
If the weather is cold and damp, the system may cause
the windows to fog while using the recirculation
mode.
If the windows do start to fog, select defog or
front defrost mode
a NC (Air Conditioning): Press this button to
manually turn the air-conditioning system on or
off.
When the system is selected, or in AUTO mode
the system will automatically begin to cool and
dehumidify the air inside
of your vehicle.
If you select air conditioning off while in front defrost, or
defog mode the air conditioning
off symbol will flash
to let you know this is not allowed.
You may notice a slight change in engine performance
when the air-conditioning compressor shuts
off and
turns
on again. This is normal.
%k (Air Conditioning Off): When you turn the air
conditioning
off, this symbol will appear on the display.
When the air conditioning is selected or in AUTO
mode, the system will run the air conditioning
automatically.
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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 floor and
windshield outlets.
@ (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 40°F (4°C) or warmer,
your air conditioning compressor will automatically run to
help dehumidify the air and dry the windshield.
Rear Window Defogger
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 approximately
10 minutes after the button is pressed. If you need
additional warming time, press the button again.
If you vehicle is equipped with heated mirrors this button
will activate them.
Notice: Don’t use a razor blade or something else
sharp on the inside
of the rear window. If you
do, you could cut or damage the defogger and the
repairs
would not be covered by your warranty.
Do not attach a temporary vehicle license, tape, a
decal or anything similar to the defogger grid.
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Outlet Adjustment Operation Tips
Use the air outlets located in the center and on the side
of your instrument panel to direct the airflow.
Your vehicle has air outlets that allow you to adjust the
direction and amount of airflow 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 airflow and temperature control, keep
the outlet in the fully opened position.
If your vehicle is equipped with rear seat outlets they
can be used
to adjust airflow toward either seating area,
the floor, or upward. Move the center louver up or
down
to direct the airflow. 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 deflectors, 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.
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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 briefly 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 lnformation Center (DIC) on page 3-43.
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Instrument Panel Cluster
Your instrument panel cluster is designed to let you know at a glance how your vehicle is running. You’ll know how
fast you’re going, about how much fuel you have and many other things you’ll need to know to drive safely and
economically.
United States version shown, Canada similar
3-25

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 two seconds 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 ip
revolutions per minute (rpm).
Notice: Do not operate the engine with the
tachometer in the red area,
or engine damage may
occur.
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 flash 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 1-57.
This light will come on
when you start your
vehicle, and it will flash 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.
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