2004 GMC SIERRA Owner's Manual

Air Bag Off Light
When you turn the right front passenger's air bag off,
this light will be lit and stay lit to remind you that the air
bag has been turned off. This light will go off when
you turn the air bag back on again. See
Air Bag
Off Switch on page 1-76for more on this, including
important safety information. The AIR BAG OFF light will
look like one of the following illustrations.
United States with Passenger Sensing System
United States without Passenger Sensing System
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Canada with Passenger Sensing SystemCanada without Passenger Sensing System
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{CAUTION:
If the right front passenger's air bag is turned
off for a person who isn't in a risk group
identi®ed by the national government, that
person won't have the extra protection of an
air bag. In a crash, the air bag wouldn't be able
to in¯ate and help protect the person sitting
there. Don't turn off the passenger's air bag
unless the person sitting there is in a risk
group. See²Air Bag Off Switch²in the Index
for more on this, including important safety
information.
{CAUTION:
If the air bag readiness light ever comes on
when you have turned off the air bag, it means
that something may be wrong with the air bag
system. The right front passenger's air bag
could in¯ate even though the switch is off.
If your vehicle is a regular cab pickup and this
ever happens, do not let anyone whom the
national government has identi®ed as a
member of a passenger air bag risk group sit
in the right front passenger's position (for
example, do not secure a rear-facing child
restraint in your vehicle) until you have your
vehicle serviced.
If your vehicle is an extended cab pickup and
this ever happens, do not let anyone whom the
national government has identi®ed as a
member of the passenger air bag risk group sit
in the right front passenger's position (for
example, do not secure a rear-facing child
restraint in the right front passenger's seat)
until you have your vehicle serviced.
3-39

Passenger Air Bag Status Indicator
If your vehicle has the passenger sensing system
your rearview mirror will have a passenger air bag status
indicator.
When the ignition key is turned to RUN or START, the
passenger air bag status indicator will light ON and
OFF, or the symbol for on and off, for several seconds
as a system check. Then, after several more seconds,the status indicator will light either ON or OFF, or either
the on or off symbol to let you know the status of the
right front passenger's frontal air bag.
If the word ON or the on symbol is lit on the passenger
air bag status indicator, it means that the right front
passenger's frontal air bag is enabled (may in¯ate).
{CAUTION:
If the on indicator comes on when you have a
rear-facing child restraint installed in the right
front passenger's seat, it means that the
passenger sensing system has not turned off
the passenger's frontal air bag. A child in a
rear-facing child restraint can be seriously
injured or killed if the right front passenger's air
bag in¯ates. This is because the back of the
rear-facing child restraint would be very close
to the in¯ating air bag. Don't use a rear-facing
child restraint in the right front passenger's seat
unless the air bag has been turned off. Passenger Air Bag Status Indicator ± United States
Passenger Air Bag
Status Indicator
± Canada
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If the word OFF or the off symbol is lit on the passenger
air bag status indicator, it means that the passenger
sensing system or the air bag off switch has turned off
the right front passenger's air bag. See
Passenger
Sensing System on page 1-81orAir Bag Off Switch on
page 1-76for more on this, including important safety
information.
{CAUTION:
If the right front passenger's air bag is turned
off for a person who isn't in a risk group
identi®ed by the national government, that
person won't have the extra protection of an
air bag. In a crash, the air bag wouldn't be able
to in¯ate and help protect the person sitting
there. Don't turn off the passenger's air bag
unless the person sitting there is in a risk
group. See²Air Bag Off Switch²in the Index
for more on this, including important safety
information.If, after several seconds, all 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 for service.
{CAUTION:
If the air bag off indicator and the air bag
readiness light ever come on together, it
means that something may be wrong with the
air bag system. If this ever happens, have the
vehicle serviced promptly, because an
adult-size person sitting in the right front
passenger seat may not have the protection of
the air bag. See²Air Bag Readiness Light²in
the Index.
3-41

Battery Warning Light
If this light is displayed
when the engine is
running, you may have a
problem with your 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 with this light displayed could drain
your battery.
If you must drive a short distance with this light
displayed, it helps to turn off all your accessories, such
as the radio and the air conditioner.
Voltmeter Gage
When your engine is not
running, but the ignition is
in RUN, this gage
shows your battery's state
of charge in DC volts.
When the engine is running, the gage shows the
condition of the charging system. Readings between the
low and high warning zones indicate the normal
operating range.
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. 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.
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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
This light is used on some
models with manual
transmissions.
The shift indicator light will show you when to shift to
the next highest gear, and will help you 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 doesn't 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 isn't 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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This light should come on brie¯y when you turn the
ignition key to RUN. If it doesn't come on then, have it
®xed so it will be ready to warn you if there's 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, the pedal may go closer to the
¯oor. It may take longer to stop. If the light is still on,
have the vehicle towed for service. See
Towing
Your Vehicle on page 4-53.
{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. United States
Canada
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