service GMC SIERRA 2006 Owner's Guide

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.
{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 1-78for more on this, including
important safety information.
{CAUTION:
If the airbag readiness light ever comes on
when you have turned off the airbag, it means
that something may be wrong with the airbag
system. The right front passenger’s airbag
could inate even though the switch is off.
If your vehicle is a regular cab pickup and this
ever happens, do not let anyone whom the
national government has identied as a member
of a passenger airbag risk group sit in the right
front passenger’s position (for example, do not
secure a rear-facing child restraint in your
vehicle) until you have your vehicle serviced.
If your vehicle is an extended cab pickup and
this ever happens, do not let anyone whom the
national government has identied as a member
of the passenger airbag risk group sit in the
right front passenger’s position (for example,
do not secure a rear-facing child restraint in the
right front passenger’s seat) until you have your
vehicle serviced.
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{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.
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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.
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If the light comes on while you are driving, pull off the
road and stop carefully. You may notice that the pedal
is harder to push or may go closer to the oor. It may take
longer to stop. If the light is still on, have the vehicle
towed for service. SeeTowing Your Vehicle on
page 4-62.
{CAUTION:
Your brake system may not be working properly
if the brake system warning light is on. Driving
with the brake system warning light on can lead
to an accident. If the light is still on after you
have pulled off the road and stopped carefully,
have the vehicle towed for service.
Anti-Lock Brake System
Warning Light
With the anti-lock brake
system, this light will come
on when you start your
engine and may stay on
for several seconds.
That’s normal. If the light doesn’t come on then, have it
xed so it will be ready to warn you if there is a problem.
If the light stays on, or comes on when you’re driving,
your vehicle needs service. You will also hear a chime
sound when the light is on steady. If the regular brake
system warning light isn’t on, you still have brakes, but
you don’t have anti-lock brakes. If the regular brake
system warning light is also on you don’t have anti-lock
brakes and there’s a problem with your regular brakes. In
addition to both lights, you will also hear a chime sound
on the rst occurrence of a problem and each time the
vehicle is shut off and then restarted. SeeBrake System
Warning Light on page 3-41.
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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.
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3-43

If your vehicle has an Allison transmission, and the uid
reaches temperatures of approximately 275°F (135°C)
or greater, the driver information center will display a
TRANS HOT IDLE ENGINE warning message and a
chime will sound until the temperature falls below
265°F (129°C). Pull the vehicle off the roadway when
it is safe to do so. Set the parking brake, place the
transmission in PARK (P) and allow the engine to
idle until the transmission temperature falls below
265°F (129°C). If the transmission continues to operate
above 265°F (130°C), contact your nearest dealer or
the GM Roadside Assistance Center. SeeRoadside
Assistance Program on page 7-6.
Notice:If you drive your vehicle with the
transmission temperature gage above normal
operating range, you can damage the transmission.
This could lead to costly repairs that would not be
covered by your warranty. Do not drive your vehicle
while the transmission temperature gage reading is
above normal. See your dealer for service.The following situations can cause the transmission to
operate at higher temperatures:
Towing a trailer
Hot outside air temperatures
Vehicle overloading
Hauling a large or heavy load
Low transmission uid level
High transmission uid level
Restricted air ow to the radiator and the auxiliary
transmission oil cooler (if equipped).
A temporary solution to hotter transmission operating
temperatures may be to let the transmission cool down.
If the transmission is operated at higher temperatures
on a frequent basis, seeScheduled Maintenance
(Gasoline Engine) on page 6-4for the proper
transmission maintenance intervals.
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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.
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If the Light is Flashing
The following may prevent more serious damage to
your vehicle:
Reducing vehicle speed
Avoiding hard accelerations
Avoiding steep uphill grades
If you are towing a trailer, reduce the amount
of cargo being hauled as soon as it is possible
If the light stops ashing and remains on steady,
see “If the Light Is On Steady” following.
If the light continues to ash, when it is safe to do so, stop
the vehicle. Find a safe place to park your vehicle. Turn
the key off, wait at least 10 seconds and restart the
engine. If the light remains on steady, see “If the Light Is
On Steady” following. If the light is still ashing, follow the
previous steps, and see your dealer for service as soon
as possible.
If the Light Is On Steady
You may be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully install the
cap. SeeFilling the Tank on page 5-10. The diagnostic
system can determine if the fuel cap has been left off or
improperly installed.A loose or missing fuel cap will allow fuel to evaporate
into the atmosphere. A few driving trips with the cap
properly installed should turn the light off.
Did you just drive through a deep puddle of water?
If so, your electrical system may be wet. The condition
will usually be corrected when the electrical system
dries out. A few driving trips should turn the light off.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-6. Poor fuel quality will cause
your engine not to run as efficiently as designed. You
may notice this as stalling after start-up, stalling when
you put the vehicle into gear, misring, hesitation on
acceleration, or stumbling on acceleration. (These
conditions may go away once the engine is warmed up.)
This will be detected by the system and cause the light to
turn on.
If you experience one or more of these conditions,
change the fuel brand you use. It will require at least
one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn off,
your dealer can check the vehicle. Your dealer has the
proper test equipment and diagnostic tools to x any
mechanical or electrical problems that may have
developed.
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{CAUTION:
Do not keep driving if the oil pressure is low.
If you do, your engine can become so hot that
it catches re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Lack of proper engine oil maintenance may
damage the engine. The repairs would not be covered
by your warranty. Always follow the maintenance
schedule in this manual for changing engine oil.
Security Light
This light ashes when the
vehicle security system is
activated.
Cruise Control Light
This light comes on
whenever you set
your cruise control.
The light will go out when the cruise control is turned off.
SeeCruise Control on page 3-10for more information.
Highbeam On Light
This light will come on
when the high-beam
headlamps are in use.
SeeHeadlamp High/Low-Beam Changer on page 3-8.
3-49

OIL PRESSURE LOW
Notice:If you drive your vehicle while the engine oil
pressure is low, severe engine damage may occur.
If a low oil pressure warning appears on the Driver
Information Center (DIC), stop the vehicle as soon as
possible. Do not drive the vehicle until the cause of
the low oil pressure is corrected. SeeEngine Oil
(Gasoline Engine) on page 5-20for more information.
If low oil pressure levels occur, this message will be
displayed on the DIC and a chime will sound. Stop the
vehicle as soon as safely possible and do not operate it
until the cause of the low oil pressure has been corrected.
Check your oil as soon as possible and have your vehicle
serviced by your GM dealer. SeeEngine Oil (Gasoline
Engine) on page 5-20.
PASSENGER DOOR AJAR
If the passenger’s door is not fully closed, this message
will appear on the display and you will hear a chime. Stop
and turn off the vehicle, check the door for obstacles and
close the door again. Check to see if the message still
appears on the DIC. Pressing any of the four DIC buttons
will acknowledge the message and clear it from the DIC
display. If your vehicle does not have the four DIC
buttons, pressing the trip odometer reset stem will
acknowledge the message and clear it from the
DIC display.
RANGE SHIFT INHIBITED
(Allison Transmission®Only)
If the transmission is unable to shift into a selected gear,
this message will appear on the DIC. The electronic shift
position indicator on the instrument panel cluster may
blink when this occurs. To make the vehicle shift to the
requested gear, you may have to shift back to PARK (P)
or NEUTRAL (N) and re-select the desired gear.
REDUCED ENGINE POWER
This message is displayed when the cooling system
temperature gets too hot and the engine further enters
the engine coolant protection mode.
SeeEngine Overheating on page 5-37for additional
information.
RIGHT REAR DOOR AJAR (Crew Cab)
If the passenger’s side rear door is not fully closed, this
message will appear on the display and you will hear a
chime. Stop and turn off the vehicle, check the door for
obstacles and close the door again. Check to see if the
message still appears on the DIC. Pressing any of the
four DIC buttons will acknowledge the message and clear
it from the DIC display. If your vehicle does not have the
four DIC buttons, pressing the trip odometer reset stem
will acknowledge the message and clear it from the
DIC display.
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