Instrument Panel Overview...............................3-4
Hazard Warning Flashers................................3-6
Other Warning Devices...................................3-6
Horn .............................................................3-6
Tilt Wheel.....................................................3-7
Turn Signal/Multifunction Lever.........................3-7
Turn and Lane-Change Signals........................3-8
Headlamp High/Low-Beam Changer..................3-8
Windshield Wipers..........................................3-9
Windshield Washer.......................................3-10
Cruise Control..............................................3-10
Exterior Lamps.............................................3-14
Headlamps on Reminder................................3-15
Daytime Running Lamps (DRL).......................3-15
Marker Lamps..............................................3-16
Instrument Panel Brightness...........................3-16
Dome Lamps ...............................................3-16
Entry Lighting...............................................3-17
Reading Lamps............................................3-17
Instrument Panel Switchbank..........................3-18
Accessory Power Outlet(s).............................3-19
Ashtray(s) and Cigarette Lighter......................3-20Climate Controls............................................3-20
Climate Control System.................................3-20
Outlet Adjustment.........................................3-24
Rear Heating System....................................3-24
Warning Lights, Gages, and Indicators............3-25
Instrument Panel Cluster................................3-26
Speedometer and Odometer...........................3-27
Trip Odometer..............................................3-27
Tachometer.................................................3-27
Engine Speed Limiter....................................3-28
Safety Belt Reminder Light.............................3-28
Safety Belt Reminder Tone............................3-28
Airbag Readiness Light..................................3-29
Airbag Off Light............................................3-30
Charging System Light..................................3-31
Voltmeter Gage............................................3-32
Service Transmission Warning Light................3-32
Range Inhibit Warning Indicator......................3-33
Brake System Warning Light..........................3-33
Anti-Lock Brake System Warning Light.............3-35
Trailer Anti-Lock Brake System Warning Light . . .3-36
Engine Coolant Temperature Gage..................3-36
Section 3 Instrument Panel
3-1
Low Coolant Warning Light............................3-37
Wait to Start Indicator (Diesel Engine).............3-37
Malfunction Indicator Lamp.............................3-38
Oil Pressure Gage........................................3-38
Low Oil Level Light.......................................3-39
Change Engine Oil Light................................3-40
Engine Overspeed Warning Light....................3-40
Engine Shutdown Warning Light.....................3-40
Transmission Temperature Gage.....................3-41
Exhaust Brake Indicator Light.........................3-41
Differential Lock Indicator Light.......................3-42
Reduced Engine Power Light.........................3-42
Highbeam On Light.......................................3-43
Daytime Running Lamps (DRL)
Indicator Light...........................................3-43
Low Washer Fluid Warning Light.....................3-44
Check Gages Warning Light...........................3-44Fuel Gage...................................................3-45
Water in Fuel Warning Light...........................3-46
Air Filter Restriction Indicator..........................3-46
Air Pressure Gage........................................3-47
Hourmeter Gage...........................................3-47
Audio System(s).............................................3-48
Setting the Time...........................................3-49
AM-FM Radio...............................................3-50
Radio with Cassette......................................3-53
Radio with CD..............................................3-59
Theft-Deterrent Feature (Non-RDS Radios).......3-64
Radio Reception...........................................3-64
Care of the Cassette Tape Player...................3-65
Care of Your CDs.........................................3-66
Care of the CD Player...................................3-67
Fixed Mast Antenna......................................3-67
Chime Level Adjustment................................3-67
Section 3 Instrument Panel
3-2
q(Exhaust Brake Switch):SeeDiesel Engine
Exhaust Brake on page 2-27.
l(Differential Lock Control Switch):SeeRear
Axle Differential Lock Control on page 4-11.
c(Airbag On/Off Switch):SeeAirbag Off Switch on
page 1-58.
If your vehicle does not have some of the features
controlled by these switches, there will be a blank switch
marker in its place.
Accessory Power Outlet(s)
With accessory power outlets, you can plug in auxiliary
electrical equipment such as a cellular telephone or
CB radio.
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 for additional information
on accessory power outlets.
Notice:Adding any electrical equipment to your
vehicle may damage it or keep other components
from working as they should. The repairs would
not be covered by your warranty. Do not use
equipment exceeding maximum amperage rating of
20 amperes. Check with your dealer 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 your 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.
3-19
-(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 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.
3-23
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. Waiting to do repairs
can be costly – and even dangerous.
3-25
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 7.8L Diesel Engine shown, Canada, 6.6L Diesel and Gasoline Engine similar
3-26
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.
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).7.2L Caterpillar
®Diesel
Engine and 7.8L
DURAMAX
®Diesel
Engines
Gasoline and 6.6L
DURAMAX®Diesel
Engines
3-27
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.
3-28