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Accessory Power Outlet(s)
Accessory power outlets let you plug in auxiliary
electrical equipment, such as a cellular telephone.
The accessory power outlet is located on the
passenger’s side of the instrument panel.
To use an outlet, pull the cover down. When not using
it, always cover the outlet with the protective cap.
This circuit is protected by a fuse and has a maximum
current level.
Notice:Leaving electrical equipment on for
extended periods will drain the battery. Always turn
off electrical equipment when not in use and do not
plug in equipment that exceeds the maximum
amperage rating.
Certain electrical accessories may not be compatible
with the accessory power outlet and could result
in blown vehicle or adapter fuses. If you experience a
problem, see your dealer/retailer for additional
information on accessory power outlets.
Notice:Adding any electrical equipment to the
vehicle can damage it or keep other components
from working as they should. The repairs would not
be covered by the vehicle warranty. Do not use
equipment exceeding maximum amperage rating of
20 amperes. Check with your dealer/retailer before
adding electrical equipment.When adding electrical equipment, be sure to follow the
proper installation instructions included with the
equipment.
Notice:Improper use of the power outlet can cause
damage not covered by the warranty. Do not hang
any type of accessory or accessory bracket from the
plug because the power outlets are designed for
accessory power plugs only.
Ashtray(s) and Cigarette Lighter
For vehicles with an ashtray and a cigarette lighter, they
are located in the center floor console. To open the
removable ashtray, flip open the top.
Notice:If papers, pins, or other flammable items
are put in the ashtray, hot cigarettes or other
smoking materials could ignite them and possibly
damage the vehicle. Never put flammable items
in the ashtray.
To use the cigarette lighter, push it in all the way and let
it go. When it’s ready, it will pop back out by itself.
Notice:Holding a cigarette lighter in while it
is heating does not let the lighter back away from
the heating element when it is hot. Damage from
overheating can occur to the lighter or heating
element, or a fuse could be blown. Do not hold a
cigarette lighter in while it is heating.
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Climate Controls
Climate Control System
The heating, cooling, and ventilation for the vehicle can
be controlled with these systems.
A. Fan Control
B. Temperature Control
C. Air Delivery Mode Control
9(Off):Turns the system off.
Temperature Control:Turn clockwise or
counterclockwise to increase or decrease the
temperature.
9(Fan):Turn clockwise or counterclockwise to
increase or decrease the fan speed. To turn the fan off,
turn the air delivery control counterclockwise to the off
position.Air Delivery Mode Control:Turn clockwise or
counterclockwise to change the direction of the airflow
inside the vehicle.
To change the current mode, select one of the following:
H(Vent):Air is directed to the instrument panel vents.
)(Bi-Level):Air is divided between the instrument
panel and floor vents. Cooler air is directed to the upper
vents and warmer air to the floor vents.
6(Floor):Air is directed 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.
-(Defog):This mode clears the windows of fog or
moisture. Outside air is directed to 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 mode removes fog or frost from the
windshield more quickly. Air is directed to 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 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. Vehicles Without Air Conditioning
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A. Fan Control
B. Temperature Control
C. Air Delivery Mode
ControlD. Rear Window
Defogger
On hot days, open the windows to let hot inside air
escape; then close them. This helps to reduce the time
it takes for the vehicle to cool down. It also helps the
system to operate more efficiently.
Air Delivery Mode Control:Turn clockwise or
counterclockwise to change the direction of the airflow
inside the vehicle.
Select from the following modes:
<(Maximum Air Conditioning):For maximum
cooling. The system goes into recirculation mode and
helps to maximize the air conditioner’s performance and
the vehicle’s fuel economy. This setting also cools the air
the fastest.
Y(Air Conditioning):For normal cooling on hot days.
Outside air is cooled and directed to the instrument
panel vents.
)(Bi-Level Air Conditioning):Air is divided between
the floor and instrument panel vents. The air conditioning
compressor cycles continuously in this setting as long as
the outside temperature is warm enough to activate the
compressor.
H(Vent):Air is directed to the instrument panel vents.
6(Floor):Air is directed 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.
-(Defog):This mode clears the windows of fog or
moisture. Outside air is directed to 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 mode removes fog or frost from the
windshield more quickly. Air is directed to 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 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. Vehicles With Air Conditioning
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Rear Window Defogger
For vehicles with a rear window defogger, a warming
grid is used to remove fog or frost from the rear window.
The rear window defogger only works when the
ignition is in ON/RUN.
<(Rear):Press to turn the rear window defogger on
or off. An indicator light comes on to show that the
rear window defogger is on. Be sure to clear as much
snow from the rear window as possible.
The rear window defogger turns off several minutes
after the button is pressed. The defogger can also be
turned off by turning off the engine.
Notice:Do not use anything sharp on the inside of
the rear window. If you do, you could cut or damage
the warming grid, and the repairs would not be
covered by the vehicle warranty. Do not attach a
temporary vehicle license, tape, a decal or anything
similar to the defogger grid.
Outlet Adjustment
The vehicle has air outlets on the instrument panel that
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 the windows.
•Keep the air path under the front seats clear of
objects. This helps air to circulate throughout
the vehicle.
•Adding outside equipment to the front of the
vehicle, such as hood-air deflectors, may affect the
performance of the heating and air conditioning
system. Check with your dealer/retailer before
adding equipment to the outside of the vehicle.
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Rear Heating System
If the vehicle has a crew
cab and 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 all
the way down.
Warning Lights, Gages, and
Indicators
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
the warning lights and gages could prevent injury.
Warning lights come on when there may be or is a
problem with one of the vehicle’s functions. Some
warning lights come on briefly when the engine is started
to indicate they are working.
Gages can indicate when there may be or is a problem
with one of the vehicle’s functions. Often gages and
warning lights work together to indicate a problem with
the vehicle.
When one of the warning lights comes on and stays on
while driving, or when one of the gages shows there
may be a problem, check the section that explains what
to do. Follow this manual’s advice. Waiting to do
repairs can be costly and even dangerous.
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Instrument Panel Cluster
The instrument panel cluster is designed to let you know at a glance how your vehicle is running. You will know how
fast you are going, about how much fuel is left and many other things you will need to drive safely and economically.
Isuzu 6H Diesel Engine shown, 6.6L & 7.2L Diesel and Gasoline Engine similar
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Speedometer and Odometer
The speedometer shows the vehicle’s speed in both
miles per hour (mph) and kilometers per hour (km/h).
The odometer shows how far the 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.
The hourmeter gage is accessed through the trip
odometer, for more information seeHourmeter Gage on
page 3-47.
Tachometer
This gage shows the safe operating range for the
engine speed in revolutions per minute (rpm).
Engine Speed Limiter
All engines have electronic engine speed limiting. The
engine limited speeds range between 2,900 and
4,400 rpm depending on engine option content.7.2L Caterpillar Diesel
Engine and Isuzu
6H Diesel Engines
Gasoline and
6.6L DURAMAX®
Diesel Engines
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Engine Road Speed Governor
This system controls maximum vehicle speed
automatically and reduces engine power until vehicle
speed gets down to maximum governed speed.
The default setting for C4500 and C5500 models up to
19,500 lbs GVWR is 80 to 85 mph (128 to 136 km/h).
Most other models have a default setting of 75 mph
(120 km/h), although some tire sizes and tread
patterns may limit maximum speed to 55 to 65 mph
(86 to 105 km/h). You may have a label on the headliner
of your vehicle with more information on your engine
road speed governor. See your GM dealer for assistance
with programming your engine limited speed.
Safety Belt Reminders
Safety Belt Reminder Light
When the engine is started, 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 the engine is
started, a tone will sound for several seconds to remind
people to fasten their safety belts.
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