2012 GMC SIERRA 1500 service indicator

Black plate (26,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
5-26 Instruments and Controls
Antilock Brake System
(ABS) Warning Light
For vehicles with the Antilock Brake
System (ABS), this light comes on
briefly when the engine is started.
If it does not, have the vehicle
serviced by your dealer. 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.
See
Brake System Warning Light on
page 5‑25.
For vehicles with a Driver
Information Center (DIC), see Brake
System Messages on page 5‑40 for
all brake‐related DIC messages.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
Four-Wheel-Drive Light
For vehicles equipped with the
four-wheel-drive light, it 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.
See
Four-Wheel Drive on page 9‑40
for more information.
Tow/Haul Mode Light
For vehicles with the Tow/Haul
Mode feature, this light comes on
when the Tow/Haul Mode has been
activated.
For more information, see Tow/Haul
Mode on page 9‑39.

Black plate (27,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Instruments and Controls 5-27
StabiliTrak®OFF Light
This light comes on briefly while
starting the engine.
If it does not, have the vehicle
serviced by your dealer. If the
system is working normally, the
indicator light then goes off.
Press and release the Traction
Control System (TCS)/StabiliTrak
button to turn off TCS, and a
message displays in the DIC.
Press and briefly hold the TCS/
StabiliTrak button to turn off the
StabiliTrak system; the StabiliTrak
Off light comes on and a message
appears in the Driver Information
Center (DIC).If the StabiliTrak/TCS system is
off, the system does not assist in
controlling the vehicle. Turn on the
StabiliTrak/TCS system and the
indicator light turns off.
See
StabiliTrak
®System on
page 9‑55, and Ride Control System
Messages on page 5‑44 for more
information.
Traction Control System
(TCS)/StabiliTrak®Light
The TCS/StabiliTrak light comes on
briefly when the engine is started.
If the light does not come on or
stays on, have the vehicle serviced
by the dealer. If the system is
working normally, the indicator light
turns off. If the light comes on and stays
on while driving, and a message
displays in the Driver Information
Center (DIC), have the vehicle
serviced by the dealer. See
Ride
Control System Messages on
page 5‑44 for more information.
If the light flashes while driving, this
means that StabiliTrak or TCS is
assisting in controlling the vehicle.
See StabiliTrak
®System on
page 9‑55 for more information.
Tire Pressure Light
For vehicles with the Tire Pressure
Monitor System (TPMS), this light
comes on briefly when the engine
is started. It provides information
about tire pressures and the TPMS.

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5-28 Instruments and Controls
When the Light Is On Steady
This indicates that one or more
of the tires are significantly
underinflated.
A Driver Information Center (DIC)
tire pressure message may also
display. SeeTire Messages on
page 5‑45. Stop as soon as
possible, and inflate the tires to the
pressure value shown on the Tire
and Loading Information label. See
Tire Pressure on page 10‑58.
When the Light Flashes First and
Then Is On Steady
If the light flashes for about a minute
and then stays on, there may be a
problem with the TPMS. If the
problem is not corrected, the light
will come on at every ignition
cycle. See Tire Pressure Monitor
Operation on page 10‑62.Engine Oil Pressure Light
Notice: Lack of proper engine oil
maintenance can damage the
engine. Driving with the engine
oil low can also damage the
engine. The repairs would not be
covered by the vehicle warranty.
Check the oil level as soon as
possible. Add oil if required,
but if the oil level is within the
operating range and the oil
pressure is still low, have the
vehicle serviced. Always follow
the maintenance schedule for
changing engine oil.
This light comes on briefly while
starting the engine. If it does not,
have the vehicle serviced by your
dealer. If the system is working
normally the indicator light then
goes off. If the light comes on and stays on, it
means that oil is not flowing through
the engine properly. The vehicle
could be low on oil and it might
have some other system problem.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
Low Fuel Warning Light
This light, under the fuel gauge,
comes on briefly while the engine is
being started.
This light and a chime, if the vehicle
is equipped with a radio, comes on
when the fuel tank is low on fuel.
The Driver Information Center also
displays a FUEL LEVEL LOW
message. See
Fuel System
Messages on page 5‑43 for more

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Instruments and Controls 5-29
information. When fuel is added this
light and message should go off. If it
does not, have the vehicle serviced
by your dealer.
Security Light
The security light should come on
briefly as the engine is started. If the
system is working normally, the
indicator light turns off. If it does not
come on, have the vehicle serviced
by your dealer.
If the light stays on and the engine
does not start, there could be a
problem with the theft-deterrent
system.This light is also used to indicate the
status of the anti-theft alarm system
when the ignition is turned off. The
light will flash rapidly if the alarm
system is arming and one or more
of the monitored entry points is not
closed. The light will stay on if the
alarm is arming and all entry points
are closed.
For information regarding this light
and the vehicle's security system,
see
Anti-theft Alarm System on
page 2‑11.High-Beam On Light
This light comes on when the
high-beam headlamps are in use.
See Headlamp High/Low-Beam
Changer on page 6‑3.
Front Fog Lamp Light
For vehicles with fog lamps, this
light comes on when the fog lamps
are on.
The light goes out when the fog
lamps are turned off. See Fog
Lamps on page 6‑6 for more
information.

Black plate (43,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Instruments and Controls 5-43
be reduced the next time the vehicle
is driven. The vehicle may be driven
at a reduced speed while this
message is on, but acceleration and
speed may be reduced. Anytime
this message stays on, the vehicle
should be taken to your dealer for
service as soon as possible.
Fuel System Messages
FUEL LEVEL LOW
This message displays and a chime
may sound if the fuel level is low.
Refuel as soon as possible. See
Fuel Gauge on page 5‑14andFuel
on page 9‑68 for more information.
TIGHTEN GAS CAP
This message may display along
with the check engine light on the
instrument panel cluster if the
vehicle's fuel cap is not tightened
properly. SeeMalfunction Indicator
Lamp on page 5‑22. Reinstall the
fuel cap fully. See Filling the Tank
on page 9‑72. The diagnostic
system can determine if the fuel cap has been left off or improperly
installed. A loose or missing fuel
cap allows fuel to evaporate into the
atmosphere. A few driving trips with
the cap properly installed should
turn this light and message off.
Key and Lock Messages
REPLACE BATTERY IN
REMOTE KEY
This message displays if a Remote
Keyless Entry (RKE) transmitter
battery is low. The battery needs to
be replaced in the transmitter. See
“Battery Replacement”
under
Remote Keyless Entry (RKE)
System Operation on page 2‑3.
Lamp Messages
TURN SIGNAL ON
This message displays and a chime
sounds if a turn signal is left on for
1.2 km (0.75 mi). Move the turn
signal/multifunction lever to the off
position.
Object Detection System
Messages
PARK ASST BLOCKED SEE
OWNERS MANUAL
This message displays if there is
something interfering with the park
assist system. See Ultrasonic
Parking Assist on page 9‑61 for
more information.
PARK ASSIST OFF
After the vehicle has been started,
this message displays to remind the
driver that the URPA system has
been turned off. Press the set/reset
button or the trip odometer reset
stem to acknowledge this message
and clear it from the DIC display. To
turn the URPA system back on, see
Ultrasonic Parking Assist on
page 9‑61.

Black plate (27,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Driving and Operating 9-27
The steering can bind with the
wheels turned off center. If this
happens, move the steering wheel
from right to left while turning the
key to ACC/ACCESSORY. If this
does not work, then the vehicle
needs service.
Notice:Using a tool to force the
key to turn in the ignition could
cause damage to the switch or
break the key. Use the correct
key, make sure it is all the way in,
and turn it only with your hand.
If the key cannot be turned by
hand, see your dealer.
B (ACC/ACCESSORY): This
position lets things like the radio
and the windshield wipers operate
while the engine is off. Use this
position if the vehicle must be
pushed or towed.
C (ON/RUN): This position can
be used to operate the electrical
accessories and to display some
instrument panel cluster warning
and indicator lights. This position
can also be used for service and diagnostics, and to verify the
proper operation of the malfunction
indicator lamp as may be required
for emission inspection purposes.
The switch stays in this position
when the engine is running. The
transmission is also unlocked in this
position on automatic transmission
vehicles.
If you leave the key in the ACC/
ACCESSORY or ON/RUN position
with the engine off, the battery could
be drained. You may not be able to
start the vehicle if the battery is
allowed to drain for an extended
period of time.
D (START):
This is the position that
starts the engine. When the engine
starts, release the key. The ignition
switch returns to ON/RUN for
driving.
A warning tone will sound when
the driver door is opened and the
ignition is in ACC/ACCESSORY or
LOCK/OFF, and the key is in the
ignition.Starting the Engine
If the vehicle has a diesel engine,
see the Duramax® diesel
supplement for more information.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
Notice: Do not try to shift to
P (Park) if the vehicle is moving.
If you do, you could damage the
transmission. Shift to P (Park)
only when the vehicle is stopped.
Move the shift lever to P (Park) or
N (Neutral). The engine will not start
in any other position. To restart the
engine when the vehicle is already
moving, use N (Neutral) only.
Notice: If you add electrical parts
or accessories, you could change
the way the engine operates. Any
resulting damage would not be
covered by the vehicle warranty.
See Add-On Electrical Equipment
on page 9‑105.

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Driving and Operating 9-45
Shift the transfer case in one
continuous motion into or out of the
N (Neutral) position.
Electronic Transfer Case
The transfer case knob is located
next to the steering column.
Use the dial to shift into and out of
four-wheel drive.
Recommended Transfer Case Settings
Driving ConditionsTransfer Case Settings
2m 4m4n N
Normal YES Severe YES
Extreme YES
Vehicle in Tow* YES
*See Recreational Vehicle Towing on page 10‑93 orTowing the Vehicle on
page 10‑93.
You can choose among four driving
settings:
Indicator lights in the dial show
which setting you are in. The
indicator lights will come on briefly
when you turn on the ignition and
one will stay on. If the lights do not
come on, you should take the
vehicle to your dealer for service.
An indicator light flashes while
shifting the transfer case and
remains illuminated when the shift is complete. If for some reason the
transfer case cannot make a
requested shift, it will return to the
last chosen setting.
2
m(Two-Wheel Drive High):
This
setting is used for driving in most
street and highway situations.
The front axle is not engaged in
Two-Wheel Drive. This setting also
provides the best fuel economy.

Black plate (49,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Driving and Operating 9-49
Automatic Transfer Case
The transfer case knob is located
next to the steering column.
Use the dial to shift into and out of
Four-Wheel Drive.
You can choose among five driving
settings:
Indicator lights in the dial show
which setting you are in. The
indicator lights will come on briefly
when you turn on the ignition andone will stay on. If the lights do
not come on, you should take the
vehicle to your dealer for service.
An indicator light will flash while
shifting the transfer case. It will
remain illuminated when the shift is
complete. If for some reason the
transfer case cannot make a
requested shift, it will return to the
last chosen setting.
2
m(Two-Wheel Drive High):
This
setting is used for driving in most
street and highway situations.
The front axle is not engaged in
Two-Wheel Drive. This setting also
provides the best fuel economy.
AUTO (Automatic Four-Wheel
Drive): This setting is ideal for
use when road surface traction
conditions are variable. When
driving the vehicle in AUTO, the
front axle is engaged, but the
vehicle's power is sent only to the front and rear wheels automatically
based on driving conditions. Driving
in this mode results in slightly lower
fuel economy than Two-Wheel
Drive High.
4
m(Four-Wheel Drive High):
Use
the Four-Wheel Drive High position
when extra traction is needed, such
as on snowy or icy roads or in most
off-road situations. This setting also
engages the front axle to help drive
the vehicle. This is the best setting
to use when plowing snow.
4
n(Four-Wheel Drive Low): This
setting also engages the front axle
and delivers extra torque. You may
never need this setting. It sends
maximum power to all four wheels.
You might choose Four-Wheel Drive
Low if you are driving off-road in
deep sand, deep mud, deep snow,
and while climbing or descending
steep hills.