2007 GMC SIERRA light

If, after several seconds, both status indicator
lights remain on, or if there are no lights at
all, there may be a problem with the lights or the
passenger sensing system. See your
dealer/retailer for service.
{CAUTION:
If the airbag readiness light in the
instrument panel cluster ever comes on
and stays on, it means that something may
be wrong with the airbag system. If this
ever happens, have the vehicle serviced
promptly, because an adult-size person
sitting in the right front passenger’s seat
may not have the protection of the
airbag(s). SeeAirbag Readiness Light on
page 250for more on this, including
important safety information.
Charging System Light
If this light comes on
when the engine is
running, there could be
a problem with the
charging system.
This light 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 of the electrical
accessories, such as the radio and the blower.
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Voltmeter Gage
Your vehicle may have
a voltmeter gage.
When the ignition is in RUN, this gage indicates
the battery voltage.
When 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. If the vehicle is
operating outside the normal operating range, thecharging system light will come on. SeeCharging
System Light on page 254for more information.
The voltmeter gage may also read lower when in
fuel economy mode. This is normal.
Readings outside the normal operating range may
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.
You can only drive for a short time with the readings
outside the normal operating range. If you must
drive, turn off all unnecessary accessories.
Readings outside the normal operating range
indicate a possible problem in the electrical system.
Have the vehicle serviced as soon as possible.
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Brake System Warning Light
With the ignition on, the brake system warning
light will come on when you set the parking brake.
If you try to drive with the parking brake engaged,
a chime will sound when the vehicle speed is
greater than 5 mph (8 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.
This light may also come on due to low brake
uid. SeeBrakes on page 528for more
information.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.
{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.
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 439.
United StatesCanada
256

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 256.
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.
257

StabiliTrak®Indicator Light
If equipped, this warning
light should come on
briey when the engine
is started.
If the warning light does not come on then, have it
xed so it will be ready to warn you if there is a
problem. If it stays on, or comes on when you are
driving, there may be a problem with your
StabiliTrak
®system and your vehicle may need
service. When this warning light is on, the system
is off and will not limit wheel spin. Adjust your
driving accordingly.
This light will also ash when the StabiliTrak
®
system is active.
If the StabiliTrak
®system warning light comes on
and stays on for an extended period of time
when the system is turned on, your vehicle needs
service. SeeStabiliTrak
®System on page 381
for more information.
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 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 516.
United StatesCanada
258

Tire Pressure Light
This light comes on
briey when you turn
the ignition to RUN.
This light will also come on when one or more of
your tires are signicantly underinated.A CHECK TIRE PRESSURE message in the
Driver Information Center (DIC) will accompany
the light. SeeDIC Warnings and Messages
on page 279for more information.
Stop and check your tires as soon as it is safe to
do so. If underinated, inate to the proper
pressure. SeeTires on page 550for more
information.
This light will ash for approximately 60 seconds
and then stay on if a problem is detected with
the Tire Pressure Monitor system.
SeeTire Pressure Monitor System on page 561
for more information.
259

Malfunction Indicator Lamp
Check Engine Light
Your vehicle has 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, the emission controls
might not work as well, your vehicle’s fuel
economy might not be as good, and the engine
might not run as smoothly. This could lead
to costly repairs that might 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 can cause
this light to come on. Modications to these
systems could lead to costly repairs not
covered by your warranty. This could also
result in a failure to pass a required Emission
Inspection/Maintenance test. SeeAccessories
and Modifications on page 486.
260

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.
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
possibleIf 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 493.
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.
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