2006 GMC SIERRA warning light

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. See
DIC Warnings and Messages on page 3-55.
3-31

Tachometer
Your tachometer displays the engine speed in
revolutions per minute (rpm). See “Grade Braking
(Allison Transmission
®)” underTow/Haul Mode on
page 2-31for more information.
Notice:If you operate the engine with the
tachometer in the solid red area, your vehicle could
be damaged. The damages would not be covered by
your warranty. Do not operate the engine in the solid
red area.
Safety Belt Reminder Light
When the key is turned to RUN or START, a chime will be
provided for several seconds to remind people to buckle
their safety belts. The driver safety belt light will also be
provided 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 3-55for
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 1-81for more
information.
3-34

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. 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.
3-40

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.
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)
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.
This light should come on briey 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.
United StatesCanada
3-41

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 4-62.
{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, this light will come
on when you start your
engine and may stay on
for several seconds.
That’s normal. If the light doesn’t 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’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 rst occurrence of a problem and each time the
vehicle is shut off and then restarted. SeeBrake System
Warning Light on page 3-41.
3-42

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, your GM dealer can prepare the vehicle for
inspection.
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 3-55andEngine Oil (Gasoline
Engine) on page 5-20. United States
Canada
3-48

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 3-55for more information.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 5-5. United States
Canada
3-51

BATTERY NOT CHARGING
On some vehicles, if the battery is not charging during
operation, this message will appear on the DIC. Driving
with this problem could drain your battery. Have the
electrical system checked by your GM dealer as soon
as possible. Pressing any of the four DIC buttons will
acknowledge the message and clear it from the DIC
display. If your vehicle does not have the four DIC
buttons, pressing the trip odometer reset stem will
acknowledge the message and clear it from the DIC
display. SeeBattery Warning Light on page 3-40and
Voltmeter Gage on page 3-40.
BUCKLE PASSENGER
If your vehicle has the passenger sensing system,
this message reminds you to buckle the passenger’s
seat belt. SeePassenger Sensing System on page 1-81.
This message will display and a chime will sound when
the ignition is on, the driver’s seat belt is buckled, the
passenger’s seat belt is unbuckled with the passenger
airbag enabled, and the vehicle is in motion. You should
have the passenger buckle their seat belt.
This reminder will be repeated if the ignition is on,
the vehicle is in motion, the driver is buckled and the
passenger is still unbuckled, and the passenger airbag is
enabled. If the passenger’s seat belt is already buckled,
this message and chime will not come on.Pressing any of the four DIC buttons will acknowledge
the message and clear it from the DIC display. If
your vehicle does not have the four DIC buttons,
pressing the trip odometer reset stem will acknowledge
the message and clear it from the DIC display.
BUCKLE SEATBELT
If your vehicle has the passenger sensing system,
this message reminds you to buckle the driver’s seat
belt. SeePassenger Sensing System on page 1-81.
This message will display and a chime will sound when
the ignition is on, the driver’s seat belt is unbuckled, and
the vehicle is in motion. You should buckle your seat belt.
If the driver remains unbuckled when the ignition is
on and the vehicle is in motion, the reminder will be
repeated. If the driver’s seat belt is already buckled,
this message and chime will not come on.
This message is an additional reminder to the Safety
Belt Reminder Light in the instrument panel cluster.
SeeSafety Belt Reminder Light on page 3-34for more
information.
Pressing any of the four DIC buttons will acknowledge the
message and clear it from the DIC display. If your vehicle
does not have the four DIC buttons, pressing the trip
odometer reset stem will acknowledge the message and
clear it from the DIC display.
3-56