engine GMC SIERRA CLASSIC 2007 Service Manual

This light should come on briey when you turn
the ignition key to RUN. If it does not come
on then, have it xed so it will be ready to warn
you if there is a problem.
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 423.
{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 (ABS), this light
will come on when you
start your engine and
may stay on for several
seconds.
That is normal. If the light does not 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 are
driving, your vehicle needs service. A chime
will sound when the light stays on. If the regular
brake system warning light is not on, you still have
brakes, but you do not have ABS. If the regular
brake system warning light is also on you do
not have ABS and there is 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 254.
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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
256

Transmission Temperature Gage
Your vehicle may have a transmission
temperature gage.
When your ignition is on, the gage shows the
temperature of the transmission uid. The normal
operating range is from 100°F (38°C) to about
265°F (130°C).At approximately 265°F (130°C), the Driver
Information Center (DIC) will display a
TRANSMISSION HOT message and the
transmission will enter a transmission protection
mode. When the transmission enters the protection
mode, you may notice a change in the
transmission shifting patterns. The transmission
will return to normal shifting patterns when
the transmission uid temperature falls below
260°F (125°C).
SeeDriver Information Center (DIC) on page 265
for further information.
If your vehicle has an Allison
®transmission, and
the uid reaches temperatures of approximately
275°F (135°C) or greater, the DIC will display
a TRANS HOT IDLE ENGINE warning message
and a chime will sound until the temperature
falls below 265°F (130°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 (130°C).United StatesCanada
257

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.
258

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.
259

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.
260

Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel.
SeeGasoline Octane on page 470. 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.Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments have
or may begin programs to inspect the emission
control equipment on your vehicle. Failure to pass
this inspection could prevent you from getting a
vehicle registration.
Here are some things you need to know to help
your vehicle pass an inspection:
Your vehicle will not pass this inspection if the
check engine light is on or not working properly.
Your vehicle will not pass this inspection if
the OBD (on-board diagnostic) system determines
that critical emission control systems have not
been completely diagnosed by the system.
The vehicle would be considered not ready for
inspection. This can happen if you have recently
replaced your battery or if your battery has
run down. The diagnostic system is designed to
evaluate critical emission control systems
during normal driving. This may take several days
of routine driving. If you have done this and
your vehicle still does not pass the inspection for
lack of OBD system readiness, your GM dealer
can prepare the vehicle for inspection.
261

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
262

Here are some situations you may experience with
your fuel gage. None of these indicate a problem
with the fuel gage.
At the gas station, the fuel pump shuts off
before the gage reads full.
It takes a little more or less fuel to ll up than
the fuel gage indicated. For example, the
gage may have indicated the tank was half full,
but it actually took a little more or less than
half the tank’s capacity to ll the tank.
The gage goes back to empty when you turn
off the ignition.
If you have a diesel engine, see “Fuel Gage” in
the Diesel Engine Supplement.
Low Fuel Warning Light
The light next to the fuel gage will come on briey
when you are starting the engine.
This light comes on when the fuel tank is low on
fuel. To turn it off, add fuel to the fuel tank.
SeeFuel on page 470.
Driver Information Center (DIC)
The Driver Information Center (DIC) display is
located on the instrument panel cluster, below the
speedometer. If your vehicle has DIC buttons,
they are located on the steering wheel. The DIC
can display information such as the trip odometer,
fuel economy, customization features, and
warning/status messages.
If your vehicle does not have DIC steering wheel
buttons, you will not have all of the features
listed. Scroll through the odometer, trip odometer,
engine hours, and selected range if your vehicle
has an Allison Transmission
®by pressing the
trip odometer reset stem located on the instrument
panel cluster. Turn off, or acknowledge, DIC
messages by pressing the trip odometer reset
stem. SeeSpeedometer and Odometer on
page 246for information on features for vehicles
without DIC buttons.
265

If your vehicle has an Allison Transmission®and
the shift lever is in the MANUAL MODE (M)
position, the DIC will display the current gear
range. The DIC will also display the gear range as
it is shifted up or down. For example, if the gear
range is currently set to 6, the DIC will display
(6)54321. When thegear range is shifted down
one time, the DIC will display 6 (5)4321. See
Automatic Transmission Operation on page 140for
more information.
3(Trip Information):Press this button to
display the odometer, trip odometers, timer, engine
hours, and selected range if your vehicle has an
Allison Transmission
®.
t(Fuel Information):Press this button to
display the current range, fuel used, average fuel
economy, and engine oil life.
4(Customization):Press this button to access
the vehicle settings menu and customize the
personal settings on your vehicle.
r(Select):Press this button to reset certain
DIC functions and set your customization settings.
Pressing any of the four DIC buttons will
acknowledge DIC messages and clear them from
the DIC display.
DIC Operation and Displays
The Driver Information Center (DIC) comes on
when the ignition is on. After a short delay, the DIC
will display the information that was last displayed
before the engine was turned off.
The DIC has different modes which can be
accessed by pressing the four DIC buttons located
on the steering wheel. These buttons are trip
information, fuel information, customization, and
select. The button functions are detailed in
the following pages.
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