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Marker Lamps
If your vehicle has this feature, you can manually blink
the marker and clearance lamps.
The marker lamp defeat
switch is located in the
instrument panel
switchbank.
Press and hold the bottom of the switch to turn off the
marker and clearance lamps. When you release
the switch, the marker and clearance lamps will come
back on.
Instrument Panel Brightness
This feature controls the brightness of the instrument
panel lights.
The thumbwheel for this feature is located to the right of
the exterior lamp control.
Turn the thumbwheel up to brighten the lights. When
the thumbwheel is moved to the first position, the radio
display and transmission selection display will go to
full intensity. The instrument panel cluster will also be
dimly lit. Moving the thumbwheel up to the next position
will activate the interior dome lamps.
Dome Lamps
The dome lamps will come on when you open a door.
You can also turn the dome lamps on by moving
the thumbwheel, located to the right of the exterior lamp
control, all the way up to the second position. In this
position, the dome lamps will remain on whether a door
is open or closed.
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You can use the dome override button to set the dome
lamps to automatically come on when a door is
open, or to remain off.
The dome override button is located below the exterior
lamp control.If the dome override button is pushed in, the dome
lamps will not come on. Use this feature when you want
to leave your door(s) open for an extended period of
time and do not want to run the battery down.
If the dome override button is in the out position,
the interior lamps will work as usual.
Entry Lighting
The delayed illumination feature will allow you to
enter or exit your vehicle with the lights on for about
20 seconds, after the door is closed or the ignition
is cycled.
Reading Lamps
If your vehicle has reading lamps, press the button
next to the lamp to turn the lamp on or off.
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Ashtray(s) and Cigarette Lighter
Your vehicle may have an ashtray and a cigarette lighter
located in the center floor console. To open the
removable ashtray, flip open the top.
Notice:If you put papers, pins, 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 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.
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:
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.Vehicles Without 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.
Be sure to clear as much snow from the rear window
as possible.
Press this button located
near the fan control to turn
the rear window defogger
on or off.
An indicator light in the button comes on when the rear
window defogger is working.
The rear window defogger will only work when the
ignition is in RUN.
The rear window defogger turns 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: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 your warranty. Do not attach a
temporary vehicle license, tape, a decal or anything
similar to the defogger grid.
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, 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 you have a crew cab
and 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 all
the way 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 are 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
is 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. Waiting to do repairs can
be costly and even dangerous.
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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.
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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Airbag Readiness Light
If your vehicle has airbags, there is an airbag readiness
light on the instrument panel, which shows the airbag
symbol. The system checks the airbag’s electrical
system for malfunctions. The light tells you if there is an
electrical problem. The system check includes the
airbag sensors, the airbag modules, the wiring, the
passenger airbag suppression circuit and the crash
sensing and diagnostic module. For more information on
the airbag system, seeAirbag System on page 1-48.
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 airbag readiness light stays on after you start the
vehicle or comes on when you are driving, your
airbag system may not work properly. Have your vehicle
serviced right away.The airbag readiness light should flash for a few
seconds when you turn the ignition key to RUN or
START. If the light doesn’t come on then, have it fixed
so it will be ready to warn you if there is a problem.
{CAUTION:
If the airbag readiness light stays on after you
start your vehicle, it means the airbag system
may not be working properly. The airbags in
your vehicle may not in ate in a crash, or they
could even in ate without a crash. To help
avoid injury to yourself or others, have your
vehicle serviced right away if the airbag
readiness light stays on after you start your
vehicle.
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Airbag Off Light
If your vehicle has an airbag on-off switch, it also has
a passenger airbag status indicator located in the
instrument panel.
When you manually turn the right front passenger’s
airbag off using the airbag on-off switch on the
instrument panel, the indicator light OFF or the off
symbol will come on and stay on to remind you that the
airbag has been turned off. This light will go off when
you turn the airbag on. SeeAirbag Off Switch on
page 1-56for more on this, including important safety
information.{CAUTION:
If the right front passenger’s airbag is turned off
for a person who is not in a risk group identi ed
by the national government, that person will not
have the extra protection of an airbag. In a
crash, the airbag will not be able to in ate and
help protect the person sitting there.
Do not turn off the passenger’s airbag unless
the person sitting there is in a risk group
identi ed by the national government.
SeeAirbag Off Switch on page 1-56for more on
this, including important safety information.
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