2009 GMC SIERRA warning light

Airbag Readiness Light
The system checks the airbag’s electrical system for
possible malfunctions. If the light stays on it indicates
there is an electrical problem. The system check
includes the airbag sensor, the pretensioners, the airbag
modules, the wiring and the crash sensing and
diagnostic module. For more information on the airbag
system, seeAirbag System on page 1-73.
The airbag readiness light
ashes for a few seconds
when the engine is started.
If the light does not come
on then, have it xed
immediately.{CAUTION:
If the airbag readiness light stays on after the
vehicle is started or comes on while driving, it
means the airbag system might not be working
properly. The airbags in the vehicle might not
inate in a crash, or they could even inate
without a crash. To help avoid injury, have the
vehicle serviced right away.
If there is a problem with the airbag system, an airbag
Driver Information Center (DIC) message can also come
on. SeeDIC Warnings and Messages on page 3-66
for more information.
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Charging System Light
This light comes on briey
when the ignition key is
turned to START, but
the engine is not running,
as a check to show it
is working.
If it does not, have the vehicle serviced by your
dealer/retailer.
The light should go out once the engine starts. If it
stays on, or comes on while driving, there could be a
problem with the charging system. A charging system
message in the Driver Information Center (DIC) can also
appear. SeeDIC Warnings and Messages on page 3-66
for more information. This light could indicate that
there are problems with a generator drive belt, or that
there is an electrical problem. Have it checked right
away. If the vehicle must be driven a short distance with
the light on, turn off accessories, such as the radio
and air conditioner.
Voltmeter Gage
For vehicles with a
voltmeter gage, this gage
indicates the battery
voltage when the ignition
is turned on.
When the ignition is on, this gage indicates the
battery voltage.
When the engine is running, this gage shows the
condition of the charging system. The gage can
transition from a higher to lower or a lower to higher
reading. This is normal. If the vehicle is operating
outside the normal operating range, the charging system
light comes on. SeeCharging System Light on
page 3-41for more information. The voltmeter gage
may also read lower when in fuel economy mode.
This is normal.
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Readings outside the normal operating range can also
occur when a large number of electrical accessories
are operating in the vehicle and the engine is left idling
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.
The vehicle can only be driven for a short time with the
readings outside the normal operating range. If the
vehicle must be driven, turn off all accessories, such as
the radio and air conditioner.
Readings outside the normal operating range indicate a
possible problem in the electrical system. Have the
vehicle serviced as soon as possible.Brake System Warning Light
With the ignition on, the brake system warning light
comes on when the parking brake is set. If the vehicle is
driven with the parking brake engaged, a chime sounds
when the vehicle speed is greater than 5 mph (8 km/h).
The vehicle’s hydraulic brake system is divided into
two parts. If one part is not working, the other part can
still work and stop the vehicle. For good braking,
both parts need to be working well.
If the warning light comes on and a chime sounds there
could be a brake problem. Have the brake system
inspected right away.
This light can also come on due to low brake uid.
SeeBrakes on page 5-40for more information.
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This light comes on briey when the ignition key is
turned to ON/RUN. If it does not come on then, have it
xed so it is ready to warn if there is a problem.
{CAUTION:
The brake system might not be working properly if
the brake system warning light is on. Driving with
the brake system warning light on can lead to a
crash. If the light is still on after the vehicle has
been pulled off the road and carefully stopped,
have the vehicle towed for service.
If the light comes on while driving, pull off the road and
stop carefully. The pedal might be harder to push or
might go closer to the oor. It can take longer to stop.
If the light is still on, have the vehicle towed for service.
SeeTowing Your Vehicle on page 4-45.
Antilock Brake System (ABS)
Warning Light
For vehicles with the
Antilock Brake System
(ABS), this light comes on
briey when the engine
is started.
If it does not, have the vehicle serviced by your
dealer/retailer. If the system is working normally the
indicator light then goes off.
If the ABS light stays on, turn the ignition off. If the light
comes on while driving, stop as soon as it is safely
possible and turn the ignition off. Then start the engine
again to reset the system. If the ABS light stays on,
or comes on again while driving, the vehicle needs
service. If the regular brake system warning light is
not on, the vehicle still has brakes, but not antilock
brakes. If the regular brake system warning light is also
on, the vehicle does not have antilock brakes and
there is a problem with the regular brakes. SeeBrake
System Warning Light on page 3-42.
For vehicles with a Driver Information Center (DIC),
seeDIC Warnings and Messages on page 3-66for all
brake related DIC messages.
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StabiliTrak®Indicator Light
For vehicles with the
StabiliTrak®system, this
light comes on briey while
starting the engine.
If it does not, have the vehicle serviced by your
dealer/retailer. If the system is working normally the
indicator light then goes off.
If the light comes on and stays on while driving, there
could be a problem with the StabiliTrak
®system and the
vehicle might need service. When this warning light is
on, the StabiliTrak
®system is off and does not limit
wheel spin.
The light ashes if the system is active and is working
to assist the driver with directional control of the
vehicle in difficult driving conditions.
SeeStabiliTrak
®System on page 4-6for more
information.
Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
It also provides an indicator of how hard the vehicle is
working. During a majority of the operation, the gage will
read 210°F (100°C) or less. If the vehicle is pulling a
load or going up hills, it is normal for the temperature
to uctuate and go over the 235°F (113°C) mark.
However, 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 5-34.
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Tire Pressure Light
For vehicles with a tire
pressure light, this light
comes on briey when the
engine is started and
provides information about
tire pressures and the
Tire Pressure Monitoring
System.
When the Light is On Steady
This indicates that one or more of the tires is signicantly
underinated.
A tire pressure message in the Driver Information
Center (DIC), can accompany the light. SeeDIC
Warnings and Messages on page 3-66for more
information. Stop and check the tires as soon as it is
safe to do so. If a tire is underinated, inate to the
proper pressure. SeeTires on page 5-65for more
information.
When the Light Flashes First and Then is
On Steady
This indicates that there could be a problem with the
Tire Pressure Monitor System. The light ashes for
about a minute and stays on steady for the remainder
of the ignition cycle. This sequence repeats with
every ignition cycle. SeeTire Pressure Monitor System
on page 5-76for more information.
Malfunction Indicator Lamp
Check Engine Light
A computer system called OBD II (On-Board
Diagnostics-Second Generation) monitors operation
of the fuel, ignition, and emission control systems.
It ensures that emissions are at acceptable levels for
the life of the vehicle, helping to produce a cleaner
environment.
This light should come on
when the ignition is on, but
the engine is not running,
as a check to show it
is working. If it does not,
have the vehicle serviced
by your dealer/retailer.
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A reading outside the normal operating range can be
caused by a dangerously low oil level or some other
problem causing low oil pressure. Check the vehicle’s oil
as soon as possible. See “OIL PRESSURE LOW” under
DIC Warnings and Messages on page 3-66andEngine
Oil on page 5-15.
{CAUTION:
Do not keep driving if the oil pressure is low.
The engine can become so hot that it catches re.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.
Notice:Lack of proper engine oil maintenance
can damage the engine. The repairs would not be
covered by the vehicle warranty. Always follow
the maintenance schedule in this manual for
changing engine oil.
Oil Pressure Light
{CAUTION:
Do not keep driving if the oil pressure is low.
The engine can become so hot that it catches re.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.
Notice:Lack of proper engine oil maintenance
can damage the engine. The repairs would not be
covered by the vehicle warranty. Always follow
the maintenance schedule in this manual for
changing engine oil.
This light comes on briey while starting the engine.
If it does not, have the vehicle serviced by your
dealer/retailer. If the system is working normally the
indicator light then goes off.
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Four-Wheel-Drive Light
The four-wheel-drive light
comes on when a vehicle
with a manual transfer
case is shifted into
four-wheel drive and the
front axle engages.
Some delay between the shifting and the light coming
on is normal.
SeeFour-Wheel Drive on page 2-37for more information.
Tow/Haul Mode Light
This light comes on when
the Tow/Haul mode has
been activated.
For more information, seeTow/Haul Mode on page 2-34.
Fuel Gage
When the ignition is on, the fuel gage shows about
how much fuel is left in the fuel tank.
An arrow on the fuel gage indicates the side of the
vehicle the fuel door is on.
The gage will rst indicate empty before the vehicle
is out of fuel, but the vehicle’s fuel tank should be
lled soon.
When the fuel tank is low the FUEL LEVEL LOW
message appears. SeeDIC Warnings and Messages
on page 3-66for more information.
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