2006 GMC SIERRA service indicator

Seats and Restraint Systems........................... 1-1
Front Seats
............................................... 1-3
Rear Seats
............................................... 1-8
Safety Belts
.............................................1-11
Child Restraints
.......................................1-31
Airbag System
.........................................1-70
Restraint System Check
............................1-87
Features and Controls..................................... 2-1
Keys
........................................................ 2-3
Doors and Locks
....................................... 2-8
Windows
.................................................2-16
Theft-Deterrent Systems
............................2-19
Starting and Operating Your Vehicle
...........2-21
Mirrors
....................................................2-59
OnStar
®System
......................................2-73
Universal Home
Remote System
....................................2-75
Storage Areas
.........................................2-79
Sunroof
..................................................2-82
Vehicle Personalization
.............................2-82
Instrument Panel............................................. 3-1
Instrument Panel Overview
.......................... 3-4
Climate Controls
......................................3-21
Warning Lights, Gages, and Indicators
........3-31
Driver Information Center (DIC)
..................3-52
Audio System(s)
.......................................3-70Driving Your Vehicle....................................... 4-1
Your Driving, the Road, and Your Vehicle
..... 4-2
Towing
...................................................4-62
Service and Appearance Care.......................... 5-1
Service
..................................................... 5-4
Fuel
......................................................... 5-5
Checking Things Under
the Hood
.............................................5-12
Rear Axle
...............................................5-58
Four-Wheel Drive
.....................................5-59
Front Axle
...............................................5-60
Noise Control System
...............................5-62
Bulb Replacement
....................................5-63
Windshield Wiper Blade Replacement
.........5-71
Tires
......................................................5-72
Appearance Care
...................................5-113
Vehicle Identication
...............................5-122
Electrical System
....................................5-123
Capacities and Specications
...................5-133
Maintenance Schedule..................................... 6-1
Maintenance Schedule
................................ 6-2
Customer Assistance and Information.............. 7-1
Customer Assistance and Information
........... 7-2
Reporting Safety Defects
...........................7-13
Index................................................................ 1
2006 GMC Sierra Owner ManualM

When the vehicle detects a loss of traction, the system
will automatically engage four-wheel drive. Driving in
this mode results in slightly lower fuel economy than
Two-Wheel High.
2
m(Two-Wheel High):This setting is used for driving
in most street and highway situations. Your front axle is
not engaged in two-wheel drive. This setting also
provides the best fuel economy.
{CAUTION:
Shifting the transfer case to NEUTRAL
can cause your vehicle to roll even if the
transmission is in PARK (P). You or someone
else could be seriously injured. Be sure to set
the parking brake before placing the transfer
case in NEUTRAL. SeeParking Brake on
page 2-52.
N (NEUTRAL):Shift the vehicle’s transfer case to
N (NEUTRAL) only when towing your vehicle. See
Recreational Vehicle Towing on page 4-62orTowing
Your Vehicle on page 4-62for more information.4
m(Four-Wheel High):Use this setting when you
need extra traction, such a on snowy or icy roads or in
most off-road situations. This setting also engages your
front axle to help drive your vehicle. This is the best
setting to use when plowing snow.
4
n(Four-Wheel Low):This setting also engages
your front axle and delivers extra torque. You may never
need Four-Wheel Low. It sends maximum power to all
four wheels. You might choose Four-Wheel Low if you
are driving off-road in deep sand, deep mud, deep snow,
and while climbing or descending steep hills. When
operating in Four-Wheel Low, the gear ratio provides
additional torque when compared to four-wheel high.
The transmission gear shift feel will be exaggerated.
Indicator lights in the switches show which setting your
transfer case is in. The indicator lights will come on briey
when you turn on the ignition and one will stay on. If the
lights do not come on, you should take your vehicle to
your dealer for service. An indicator light will ash while
the transfer case is being shifted. It will stay on when the
shift is complete. If for some reason the transfer case
cannot make a requested shift, it will return to the last
chosen setting.
If the SERVICE 4WD message stays on, you should take
your vehicle to your dealer for service. SeeDIC Warnings
and Messages on page 3-55for further information.
2-43

4n(Four-Wheel Low):This setting also engages
your front axle to give you extra traction. You may never
need Four-Wheel Low. It sends the maximum power to all
four wheels. You might choose Four-Wheel Low if you
were driving off-road in sand, mud or deep snow and
while climbing or descending steep hills. When operating
in Four-Wheel Low, the gear ratio provides additional
torque when compared to Four-Wheel High. The
transmission gear shift feel will be exaggerated.
Indicator lights in the switches show you which setting
you are in. The indicator lights will come on briey when
you turn on the ignition and the last chosen setting will
stay on. If the lights do not come on, you should take your
vehicle in for service. An indicator light will ash while
shifting. Fast ashing means the conditions were not met
to make the desired shift, typically the vehicle was going
too fast, the automatic transmission was not in neutral,
or the clutch pedal was not fully pressed. Slow ashing
means the shift is in progress. It will stay on when the
shift is completed. If for some reason the transfer cannot
make a requested shift, it will return to the last chosen
setting.Shifting from Two-Wheel High to
Four-Wheel High
Press and release the Four-Wheel High switch. This
can be done at any speed, and the front axle will lock
automatically with some delay.
Shifting from Four-Wheel High to
Two-Wheel High
Press and release the Two-Wheel High switch. This
can be done at any speed, and the front axle will unlock
automatically with some delay.
It is normal to hear and feel your vehicle’s transfer case
shift into Four-Wheel Low. If you shift with the vehicle
stopped, the indicator light may remain ashing slowly.
It may be necessary to shift the transmission momentarily
into REVERSE (R) and DRIVE (D), for an automatic
transmission, or REVERSE (R) and FIRST (1) for a
manual transmission to have the light stop ashing.
2-48

Auxiliary Roof Mounted Lamp
If your vehicle has this feature, this button includes
wiring provisions for a dealer or a qualied service
center to install an auxiliary roof lamp.
This button is located
on the center of the
instrument panel near
the climate controls.
When the wiring is connected to an auxiliary roof
mounted lamp, pressing the button will activate the lamp
and illuminate an indicator light near the button. Pressing
the button again will turn off the roof mounted lamp.
If your vehicle has this button, your vehicle may have the
snow plow prep package. For further information see
Adding a Snow Plow or Similar Equipment on page 4-54.
Instrument Panel Brightness
D(Instrument Panel Brightness):This feature
controls the brightness of the instrument panel lights.
The thumbwheel for this feature is located next to
the headlamp control.
Turn the thumbwheel up to adjust the instrument panel
lights. Turn the thumbwheel up to return the radio display
to full brightness when the headlamps or parking lamps
are on. To turn on the dome lamps, turn the thumbwheel
all the way up.
Dome Lamps
The dome lamps will come on when you open a door.
You can also turn the dome lamps on by turning the
thumbwheel, located next to the exterior lamps control,
all the way up. In this position, the dome lamps will
remain on whether a door is opened or closed.
3-18

{CAUTION:
If the right front passenger’s airbag is turned
off for a person who is not in a risk group
identied 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 inate 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 1-78
for more on this, including important safety
information.
If, after several seconds, all status indicator lights remain
on, or if there are no lights at all, there may be a problem
with the lights or the passenger sensing system. See your
dealer for service.
{CAUTION:
If the airbag off indicator and the airbag
readiness light ever come on together, it means
that something may be wrong with the airbag
system. If this ever happens, have the vehicle
serviced promptly, because an adult-size
person sitting in the right front passenger seat
may not have the protection of the airbag. See
Airbag Readiness Light on page 3-35.
3-39

Readings in the low warning zone may occur when a
large number of electrical accessories are operating
in the vehicle and the engine is left at an idle for an
extended period. This condition is normal since the
charging system is not able to provide full power at
engine idle. As engine speeds are increased, this
condition should correct itself as higher engine speeds
allow the charging system to create maximum power.
You can only drive for a short time with the reading
in either warning zone. If you must drive, turn off
all unnecessary accessories.
Readings in either warning zone indicate a possible
problem in the electrical system. Have the vehicle
serviced as soon as possible.
Up-Shift Light
(Manual Transmission)
This light is used on
some models with
manual transmissions.
The shift indicator light will show you when to shift to
the next highest gear, and will help you get the best fuel
economy.
Brake System Warning Light
With the ignition on, the brake system warning light will
ash when you set the parking brake. The light will ash if
the parking brake doesn’t release fully. If you try to drive
with the parking brake engaged, a chime will sound when
the vehicle speed is greater than 3 mph (5 km/h).
Your vehicle’s hydraulic brake system is divided into
two parts. If one part isn’t working, the other part can
still work and stop you. For good braking, though,
you need both parts working well.
If the warning light comes on and a chime sounds there
could be a brake problem. Have your brake system
inspected right away.
This light should come on briey when you turn the
ignition key to RUN. If it doesn’t come on then, have it
xed so it will be ready to warn you if there’s a problem.
United StatesCanada
3-41

Traction Off Light
If you have the Traction
Assist System, this light
should come on briey
when you turn the ignition
to RUN.
If the light does not come on then, the system may
require service; have it xed so it will be there to warn
you if the system is turned off.
If the light stays on, or comes on when you are driving,
there may be a problem with your Traction Assist System
and your vehicle may need service. When this light is on,
the system will not limit wheel spin. Adjust your driving
accordingly.
Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
It also provides an indicator of how hard your vehicle
is working. During a majority of the operation, the gage
will read 210°F (100°C) or less. If you are pulling a
load or going up hills, it is normal for the temperature
to uctuate and approach the 250°F (122°C) mark. If
the gage reaches the 260°F (125°C) mark, it indicates
that the cooling system is working beyond its capacity.
SeeEngine Overheating on page 5-37.
United StatesCanada
3-43

Malfunction Indicator Lamp
Check Engine Light
Your vehicle is equipped
with a computer which
monitors operation of the
fuel, ignition, and emission
control systems.
This system is called OBD II (On-Board
Diagnostics-Second Generation) and is intended to
assure that emissions are at acceptable levels for the life
of the vehicle, helping to produce a cleaner environment.
The check engine light comes on to indicate that there is
a problem and service is required. Malfunctions often
will be indicated by the system before any problem is
apparent. This may prevent more serious damage to
your vehicle. This system is also designed to assist
your service technician in correctly diagnosing any
malfunction.
Notice:If you keep driving your vehicle with this
light on, after awhile, your emission controls may not
work as well, your fuel economy may not be as good,
and your engine may not run as smoothly. This could
lead to costly repairs that may not be covered by
your warranty.Notice:Modications made to the engine,
transmission, exhaust, intake, or fuel system of
your vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect your vehicle’s emission
controls and may cause this light to come on.
Modications to these systems could lead to costly
repairs not covered by your warranty. This may
also result in a failure to pass a required Emission
Inspection/Maintenance test. SeeAccessories
and Modifications on page 5-4.
This light should come on, as a check to show you it is
working, when the ignition is on and the engine is not
running. If the light does not come on, have it repaired.
This light will also come on during a malfunction in one of
two ways:
Light Flashing— A misre condition has been
detected. A misre increases vehicle emissions
and may damage the emission control system
on your vehicle. Diagnosis and service may be
required.
Light On Steady— An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service may be required.
3-46