warning GMC SIERRA CLASSIC 2007 User Guide

Warning Lights, Gages, and
Indicators
This part describes the warning lights and gages
on your vehicle. The pictures will help you
locate them.
Warning lights and gages can signal that
something is wrong before it becomes serious
enough to cause an expensive repair or
replacement. Paying attention to your warning
lights and gages could also save you or others
from injury.
Warning lights come on when there may be or is a
problem with one of your vehicle’s functions. As
you will see in the details on the next few
pages, some warning lights come on briey when
you start the engine just to let you know they
are working. If you are familiar with this section,
you should not be alarmed when this happens.Gages can indicate when there may be or is a
problem with one of your vehicle’s functions. Often
gages and warning lights work together to let
you know when there is a problem with your
vehicle.
When one of the warning lights comes on and
stays on when you are driving, or when one of the
gages shows there may be a problem, check
the section that tells you what to do about
it. Please follow this manual’s advice. Waiting to
do repairs can be costly – and even dangerous.
So please get to know your warning lights
and gages. They are a big help.
Your vehicle also has a Driver Information Center
(DIC) that works along with warning lights and
gages. SeeDIC Warnings and Messages
on page 270.
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Safety Belt Reminder Light
When the key is turned to RUN or START, a
chime will sound for several seconds to remind
people to buckle their safety belts. The driver
safety belt light will also come on and stay on for
several seconds, then it will ash for several
more. You should buckle your seat belt.
This chime and light will
be repeated if the driver
remains unbuckled
and the vehicle
is in motion.
SeeDIC Warnings and Messages on page 270for
more information on driver and passenger
safety belt reminders.
If the driver’s belt is buckled, neither the chime nor
the light will come on.
SeePassenger Sensing System on page 103for
more information.
Airbag Readiness Light
There is an airbag readiness light on the instrument
panel cluster, which shows the airbag symbol. The
system checks the airbag’s electrical system for
malfunctions. The light tells you if there is an
electrical problem. The system check includes the
airbag sensors, the airbag modules, the wiring and
the crash sensing and diagnostic module and, if
equipped, the passenger sensing system. For more
information on the airbag system, seeAirbag
System on page 91.
This light will come on
when you start your
vehicle, and it will ash
for a few seconds.
This means the system
is ready.
If the airbag readiness light stays on after the
vehicle is started or comes on while you are
driving, the airbag system may not be working
properly. Have your vehicle serviced right away.
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Battery Warning Light
If this light comes on
when the engine is
running, there could be
a problem with the
charging system.
The battery display will also stay on while the key
is in RUN until the engine is started.
If the light stays on after starting the engine it
could indicate a problem with the generator drive
belt, or some other charging system problem.
Have it checked right away. Driving while this light
is on could drain the battery.
If you must drive a short distance with this light
on, it helps to turn off all your accessories, such as
the radio and the air conditioner.
Voltmeter Gage
When the engine is not
running, but the ignition
is in RUN, this gage
shows your battery’s
state of charge in
DC volts.
While the engine is running, this gage shows the
condition of the charging system. The gage
may transition from a higher to lower or a lower to
higher reading. This is normal. Readings
between the low and high warning zones indicate
the normal operating range. The voltmeter
gage may also read lower when in fuel economy
mode. This is normal.
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.
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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)
Your vehicle may have
an up-shift light.
It will come on when you should shift to the next
highest gear. It will help the vehicle 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 does not
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 is not 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.
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254

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.
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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

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

Tow/Haul Mode Light
This light comes on
when the Tow/Haul
mode has been
activated.
For more information, seeTow/Haul Mode on
page 147.
Cargo Lamp Light
This light comes on
when the cargo lamp is
in use. For more
information seeCargo
Lamp on page 228.
Fuel Gage
When the ignition is on, the fuel gage tells you
about how much fuel you have left in your tank.
The gage will rst indicate empty before you
are out of fuel, and you should get more fuel as
soon as possible.
When the fuel tank is low the FUEL LEVEL LOW
message will appear. SeeDIC Warnings and
Messages on page 270for more information.
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264

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.
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