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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.
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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.
Instrument Panel Switchbank
Vehicles Without Four-Wheel Drive
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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 will not allow the lighter to back
away from the heating element when it is hot.
Damage from overheating may 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:
Turn the mode knob on the far right clockwise or
counterclockwise to direct the airflow inside of
your vehicle.
Vehicles Without Air Conditioning
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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 in 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: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 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.
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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 68.
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 is equipped with an airbag off
switch, when you turn the right front passenger’s
airbag off, this light 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 76for 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.
SeeAirbag Off Switch on page 76for
more on this, including important safety
information.
United StatesCanada
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