2006 GMC SIERRA service

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
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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.
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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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SERVICE 4WD (Four-Wheel-Drive)
If a problem occurs with the four-wheel-drive system,
this message will appear on the DIC. If this message
appears, stop as soon as possible and turn off the
vehicle. Restart the vehicle and check for the message
on the DIC display. If the message is still displayed
or appears again when you begin driving, the
four-wheel-drive system needs service. See your
GM dealer.
SERVICE AIRBAG
If there is a problem with the airbag system, this message
will be displayed on the DIC. Have your GM dealer
inspect the system for problems. SeeAirbag Readiness
Light on page 3-35andAirbag System on page 1-70for
more information. 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.
SERVICE BRAKE BOOSTER
{CAUTION:
Your brake system may not be working
properly if the SERVICE BRAKE BOOSTER
message is displayed.
If the brake system warning light is also on,
you should have the vehicle towed for service.
SeeBrake System Warning Light on page 3-41.
If the brake system warning light is not on, you
still have brakes, but the supplemental brake
assist system on vehicles with rear disc brakes
may not operate properly. In the event of a
vacuum loss, you may not have vacuum power
assist for braking. The brake pedal will be
harder to push and it will take longer to stop.
If you continue to drive with this message
displayed it can lead to a crash. Have the
brake system serviced as soon as possible.
If your vehicle has vacuum assist power brakes, this
message will be displayed on the DIC when there is a
problem with the Supplemental Brake Assist system.
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If the message is displayed immediately after starting
the vehicle or the message appears while driving,
your Supplemental Brake Assist system needs service.
See your GM dealer. SeeBrake System Warning
Light on page 3-41for additional information.
SERVICE BRAKE SYSTEM
If there is a problem with the brake system, this
message will be displayed on the DIC. If this message
appears, stop as soon as possible and turn off the
vehicle. Restart the vehicle and check for the message
on the DIC display. If the message is still displayed
or appears again when you begin driving, the brake
system needs service. See your GM dealer.
SERVICE CHARGING SYSTEM
On some vehicles, if there is a problem with the battery
charging system, this message will appear on the DIC.
Under certain conditions, the battery warning light may
also turn on in the instrument panel cluster. SeeBattery
Warning Light on page 3-40. The battery will not be
charging at an optimal rate and the vehicle will lose the
ability to enter the fuel economy mode. The vehicle is
safe to drive, however you should have the electrical
system checked by your GM dealer. 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.
TIGHTEN FUEL CAP
If the vehicle’s fuel cap is not tightened properly, this
message may appear along with the check engine light
on the instrument panel. SeeMalfunction Indicator Lamp
on page 3-46. Fully reinstall the fuel 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 and message off.
TRACTION ACTIVE
When the traction control system had detected that any
of the vehicle’s wheels are slipping, the traction control
system will activate and this message will appear on the
DIC. For more information, seeTraction Assist
System (TAS) on page 4-8.
TRANS (Transmission)
HOT IDLE ENGINE
Notice:If you drive your vehicle while the
transmission uid is overheating and the
transmission temperature warning is displayed on
the instrument panel cluster and/or DIC, you can
damage the transmission. This could lead to costly
repairs that would not be covered by your warranty.
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