2003 GMC SIERRA DENALI service

If the right front passenger’s air bag is turned
off for a person who isn’t in a risk group
identified 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 inflate 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. See
”Air Bag Off Switch” in the Index
for more on this, including important safety
information.
I he air bag readiness I r. It ever comes ~ 7
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
CAUTION: (Continued)
wuld inflate even though the svvl;ch is off. If
this ever happens, don’t let anyone whom the
national government has identified as a
member of a passenger air bag risk group
sit
in the right front passenger’s position (for
example, don’t secure a rear-facing child
restraint
in your vehicle) until you have your
vehicle serviced.
Passenger Air Bag Status Indicator
If your vehicle has the passenger sensing system your
rearview mirror will have a passenger air bag status
indicator.
Passenger Air Bag Status Indicator
- United States
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If the right front passenger’s air bag is turned
off for a person who isn’t in a risk group
identified 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 inflate 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. See ”Air Bag
Off Switch” in 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. 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. See ”Air Bag Readiness Light” in
the Index.
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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.
Brake System Warning Light
With the ignition on, the brake system warning light will
flash when you set the parking brake. The light will
flash
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.
I BRAKE I
-
United States Canada
This light should come on briefly when you turn the
ignition key
to RUN. If it doesn’t come on then, have it
fixed
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
floor. It may take longer
to stop. If the light is still on,
have the vehicle towed for service. See Towing
Your Vehicle on page 4-45.
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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’ve 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, this light will come
on when you start your
engine and may stay on for
several seconds. That’s
normal.
, I
If the light doesn’t come on then, have it fixed so it will
be ready to warn you
if there is a problem.
If the light stays on, or comes on when you’re driving,
your vehicle needs service.
You will also hear a
chime sound when the light
is on steady. If the regular
brake system warning light isn’t on, you still have
brakes, but you don’t have anti-lock brakes. If the
regular brake system warning light is also on you don’t
have anti-lock brakes and there’s a problem with
your regular brakes.
In addition to both lights, you will
also hear a chime sound on the first occurrence of
a problem and each time the car is shut
off and then
restarted. See
Brake System Warning Light on
page 3-34 earlier in this section.
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Malfunction Indicator Lamp
Check Engine Light
Your vehicle is equipped
with a computer which
monitors operation of the
fuel, ignition and emission
control systems.
I I
This system is called OBD I1 (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 a while, 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: Modifications 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.
Modifications to these 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.
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 doesn’t come on, have it
repaired. This light will also come on during a
malfunction in one of two ways:
Light Flashing - A misfire condition has been
detected.
A misfire increases vehicle emissions
and may damage the emission control system on
your vehicle. Dealer or qualified service center
diagnosis and service may be required.
Light On Steady - An emission control system
malfunction has been detected on your vehicle.
Dealer or qualified service center diagnosis
and service may be required.
3-38

If the Light is Flashing
The following may prevent more serious damage to
your vehicle:
Reducing vehicle speed.
Avoiding hard accelerations.
0 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 flashing and remains on steady, see “If
the Light
Is On Steady” following.
If the light continues to flash, 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
flashing, follow the previous steps, and drive the vehicle
to your dealer or qualified service center for service.
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. See
Fi//ing Your Tank on page 5-7. 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.
Have you recently changed brands of fuel?
If
so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-5. 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, misfiring, 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,
have your dealer or qualified service center check
the vehicle. Your dealer has the proper test equipment
and diagnostic tools to
fix any mechanical or electrical
problems that may have developed.
3-39

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, see your dealer or qualified service
center to prepare the vehicle for inspection.
Oil Pressure Gage
I I
United States Canada
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.
3-40

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
DIC Warnings and Messages on
page 3-53
and ‘vgine Oil on page 5-13.
Don’t keep driving if the oil pressure is low. If
you do, your engine can become
so hot that it
catches fire. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice: Damage to your engine from neglected oil
problems can be costly and is not covered by
your warranty.
Cruise Control Light
The cruise light comes on
whenever you set your
cruise control. See “Cruise
Control” under
Turn
SignaVMultifunction Lever
on page 3-5.
Tow/HauI Mode Light
This light is displayed
when the tow/haul mode
has been activated.
For more information, see
Towing a Trailer on
page 4-5
I.
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