2007 GMC SIERRA CLASSIC service

The ABS warning light should come on briey
when you turn the ignition key to RUN. If the light
does not come on then, have it xed so it will
be ready to warn you if there is a problem.
Traction Off Light
If your vehicle has 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 505.
United StatesCanada
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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 644.
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
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 reduce 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 617for the proper transmission
maintenance intervals.
Malfunction Indicator Lamp
Check Engine Light
Your vehicle has a
computer which
monitors operation of
the fuel, ignition,
and emission control
systems.
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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 tothese 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 468.
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 474.
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.
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Oil Pressure Gage
The oil pressure gage shows the engine oil
pressure in psi (pounds per square inch) when the
engine is running. Canadian vehicles indicate
pressure in kPa (kilopascals).
Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but readings
above the low pressure zone indicate the normal
operating range.A reading in the low pressure zone may be
caused by a dangerously low oil level or some
other problem causing low oil pressure. Check
your oil as soon as possible. See “OIL PRESSURE
LOW” underDIC Warnings and Messages on
page 270andEngine Oil (Gasoline Engine)
on page 486.
{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.United StatesCanada
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If your vehicle has a low coolant level sensor, this
message will appear on the DIC if the engine
coolant level is low. Adding coolant to the coolant
recovery tank will clear the message. See
Cooling System on page 508. 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.
OIL LIFE RESET
This message will appear on the display for about
10 seconds after resetting the change engine
oil message. See “Engine Oil Life System” under
DIC Operation and Displays on page 266and
Engine Oil (Gasoline Engine) on page 486
for more information.
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. See
Engine Oil (Gasoline Engine) on page 486
for 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 the oil as
soon as possible and have your vehicle serviced
by your dealer. SeeEngine Oil (Gasoline Engine)
on page 486.
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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 obstructions, 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 505for further
information.
This message will also display when the vehicle’s
engine power is reduced. Reduced engine
power can affect the vehicle’s ability to accelerate.
If this message is on, but there is no reduction
in performance, proceed to your destination. The
performance may be reduced the next time
the vehicle is driven. The vehicle may be driven at
a reduced speed while this message is on, but
acceleration and speed may be reduced. Anytime
this message stays on, the vehicle should be
taken to your dealer for service as soon as
possible.
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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 obstructions, 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.
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 dealer.
SERVICE AIRBAG
If there is a problem with the airbag system, this
message will be displayed on the DIC. Have
your dealer inspect the system for problems. See
Airbag Readiness Light on page 247and
Airbag System on page 91for 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.
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