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Climate Controls
Climate Control System
With these systems, you can control the heating,
cooling and ventilation for your vehicle.
If your vehicle does not have air conditioning, the
controls will look like this:
Turn the mode knob on the far right clockwise or
counterclockwise to direct the airflow inside of your
vehicle.
To change the current mode, select one of the following:
9(OFF):This setting turns the system off.
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 the remaining
air to the floor vents. Cooler air is directed to the upper
vents and warmer air to the floor vents.
6(Floor):This mode directs most of the air to the
floor 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 mode knob can also be used to select the defrost
mode. For more information, see “Defogging and
Defrosting” later in this section.
9(Fan):Turn the left knob clockwise or
counterclockwise to increase or decrease the fan speed.
To increase airflow, turn the knob clockwise. To
decrease airflow, turn it counterclockwise. To turn the
fan off, turn the mode knob on the far right
counterclockwise to the off position.
(Temperature Knob):Turn the middle knob located
clockwise or counterclockwise to increase or decrease
the temperature inside of your vehicle. Turn the
knob toward the red area for warmer air. Turn the knob
toward the blue area for cooler air.
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If your vehicle has air conditioning, the controls will look
like this:
On hot days, open the windows to let hot inside air
escape; then close them. This helps to reduce the time
it takes for your vehicle to cool down. It also helps
the system to operate more efficiently.
<(Maximum Air Conditioning):Turn the right knob
to this setting for maximum cooling. This setting puts
the system in recirculation mode and helps to maximize
your air conditioner’s performance and your vehicle’s
fuel economy. This setting also cools the air the fastest.
Y(Air Conditioning):This setting is used for normal
cooling on hot days. It cools outside air and directs
it through the instrument panel vents.
)(Bi-Level Air Conditioning):This setting divides
airflow between the floor vents and instrument panel
vents. The air conditioning compressor will cycle
continuously in this setting as long as the outside
temperature is warm enough to activate the compressor.
Defogging and Defrosting
Fog on the inside of windows is a result of high humidity
(moisture) condensing on the cool window glass. This
can be minimized if the climate control is used properly.
There are two modes to clear fog or frost from your
windshield and side windows.
Use the defog mode to clear the windows of fog or
moisture and warm the passengers. Use the defrost
mode to remove fog or frost from the windshield more
quickly. For best results, clear all snow and ice from the
windshield before defrosting.
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Turn the mode knob on the right of the climate control
panel to select the defog or defrost mode.
-(Defog):With this setting, the outside air comes out
of both the floor and defroster outlets. Adjust the
temperature knob for warmer or cooler air. The air
conditioning compressor may operate in this setting to
dehumidify the air.
0(Defrost):This setting operates the defroster. Most
of the air comes out near the windshield, with some
going to the floor outlets and front side windows. The air
conditioning compressor may operate in this setting to
dehumidify the air.
The defog setting is useful for cold weather with a large
number of passengers or very humid conditions to
help keep the windshield clear. Use defrost to remove
fog or ice from the windshield quickly in extremely
cold conditions. The temperature knob should be in the
red area and the fan control toward high. Do not
drive the vehicle until all the windows are clear.
Rear Window Defogger
The rear window defogger uses a warming grid to
remove fog or frost from the rear window.Be sure to clear as much snow from the rear window as
possible.
Press this button which is
located near the fan
control to turn the rear
window defogger on or off.
An indicator light in the
button will come on when
the rear window defogger
is working.
The rear window defogger will only work when the
ignition is RUN.
The rear window defogger will turn off several minutes
after the button is pressed. The defogger can also
be turned off by pressing the button again or by turning
off the engine.
Notice:Don’t use anything sharp on the inside of
the rear window. If you do, you could cut or damage
the warming grid, and the repairs wouldn’t 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
Your vehicle has air outlets
on the instrument panel
that allow you to adjust the
direction and amount of
airflow inside the vehicle.
Move the lever on the outlet up or down to direct the
airflow. Increase or reduce the amount of airflow
by opening and closing the louvers. The outlets can be
moved side-to-side to direct the airflow.
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 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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Rear Heating System
If your vehicle has a rear
heater, the thumbwheel for
this feature is located on
the headliner.
To increase and decrease the flow of heated air to
the rear floor vents, turn the thumbwheel to the
desired fan speed. To turn the fan off, turn the
thumbwheel down.
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.
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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 your going, about how much fuel is left and many other things you’ll need to drive safely and economically.
United States Diesel Engine shown, Canada and Gasoline Engine similar
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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.
While the engine is running, press the reset button,
located to the right of the trip odometer, to toggle
between the trip odometer and the regular odometer.
Holding the reset button for two seconds while the
engine is running and the trip odometer is displayed,
will reset it.
To display the odometer reading with the ignition off,
press the reset button.
Engine Speed Limiting
All engines have electronic engine speed limiting.
The engine limited speeds range between
2,900 and 4,400 rpm depending on engine
option content.
Engine Road Speed Governor
This system controls maximum vehicle speed
automatically and reduces engine power until vehicle
speed gets down to maximum governed speed.
A 75 mph (120 km/h) road speed governor is standard
for most models, but can be programmed to any
speed below that default setting. Other models have a
default setting of 80 to 85 mph (128 to 136 km/h).
You may have a label on the headliner of your vehicle
with more information on your engine road speed
governor. See your dealer for assistance with
programming your engine limited speed.
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Tachometer
This gage shows the engine speed in revolutions per
minute (rpm).
Safety Belt Reminder Light
When the key is turned to RUN or START, a light will
come on for several seconds to remind people to fasten
their safety belts.
The safety belt light will
also come on and stay on
for several seconds.
Safety Belt Reminder Tone
If your vehicle has this feature, when you turn your key
to RUN or START, a tone will sound for several
seconds to remind people to fasten their safety belts. 7.2L Caterpillar
®Diesel
Engine and 7.8L
DURAMAX™ Diesel
EnginesGasoline and 6.6L
DURAMAX™ Diesel
Engines
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