warning GMC YUKON 2012 Repair Manual

Black plate (16,1)GMC Yukon/Yukon XL Owner Manual - 2012
5-16 Instruments and Controls
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 the
oil as soon as possible.
{WARNING
Do not keep driving if the oil
pressure is low. The engine can
become so hot that it catches fire.
Someone could be burned. Check
the oil as soon as possible and
have the vehicle serviced.
Notice: Lack of proper engine oil
maintenance can damage the
engine. The repairs would not be
covered by the vehicle warranty.
Always follow the maintenance
schedule for changing engine oil.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
Engine Coolant
Temperature Gauge
Metric
English
This gauge shows the engine
coolant temperature.
It also provides an indicator of how
hard the vehicle is working. During a
majority of the operation, the gauge
reads 100°C (210°F) or less. If you
are pulling a load or going up hills, it
is normal for the temperature to
fluctuate and approach the 122°C
(250°F) mark. If the gauge reaches
the 125°C (260°F) mark, it indicates
that the cooling system is working
beyond its capacity.

Black plate (17,1)GMC Yukon/Yukon XL Owner Manual - 2012
Instruments and Controls 5-17
SeeEngine Overheating on
page 10‑21.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
Voltmeter Gauge
When the engine is not running, but
the ignition is on, this gauge shows
the battery's state of charge in
DC volts. When the engine is running, the
gauge shows the condition of the
charging system. The charging
system regulates voltage based on
the state of the battery for improved
fuel economy and battery life. The
gauge 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 gauge may also read
low during the fuel economy mode,
this is normal.
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 full
power. If there is a problem with the
battery charging system, this lightwill come on or the SERVICE
BATTERY CHARGING SYSTEM
DIC message will display. See
Battery Voltage and Charging
Messages on page 5‑38
and
Charging System Light on
page 5‑20 for more information.
Safety Belt Reminders
Driver Safety Belt Reminder
Light
There is a driver safety belt
reminder light on the instrument
panel cluster.
When the vehicle is started, this
light flashes and a chime may come
on to remind the driver to fasten
their safety belt. Then the light stays
on solid until the belt is buckled.

Black plate (19,1)GMC Yukon/Yukon XL Owner Manual - 2012
Instruments and Controls 5-19
{WARNING
If the airbag readiness light stays
on after the vehicle is started or
comes on while driving, it means
the airbag system might not be
working properly. The airbags in
the vehicle might not inflate in a
crash, or they could even inflate
without a crash. To help avoid
injury, have the vehicle serviced
right away.
If there is a problem with the airbag
system, a Driver Information Center
(DIC) message can also come on.
See Airbag System Messages on
page 5‑44 for more information.
Passenger Airbag Status
Indicator
If the vehicle has the airbag status
indicator pictured in the following
illustration, then the vehicle has a
passenger sensing system for the
right front passenger position. The
passenger airbag status indicator is
on the overhead console. See
Passenger Sensing System on
page 3‑38for important safety
information.
In addition, if the vehicle has a
passenger sensing system for the
right front passenger position, the
label on the vehicle's sun visors
refers to “ADVANCED AIRBAGS.”
United States
Canada
When the vehicle is started, the
passenger airbag status indicator
will light ON and OFF, or the
symbols for on and off, for several
seconds as a system check. If you
are using remote start, if equipped,
to start the vehicle from a distance,
you may not see the system check.

Black plate (20,1)GMC Yukon/Yukon XL Owner Manual - 2012
5-20 Instruments and Controls
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 frontal
airbag.
If the word ON or the on symbol is
lit on the passenger airbag status
indicator, it means that the right
front passenger frontal airbag is
enabled (may inflate).
If the word OFF or the off symbol is
lit on the airbag status indicator, it
means that the passenger sensing
system has turned off the right front
passenger frontal airbag.
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 for service.{WARNING
If the airbag readiness light ever
comes on and stays on, it means
that something may be wrong
with the airbag system. To help
avoid injury to yourself or others,
have the vehicle serviced right
away. SeeAirbag Readiness
Light on page 5‑18 for more
information, including important
safety information.
Charging System Light
This light comes on briefly when the
ignition key is turned to START, but
the engine is not running, as a
check to show it is working. If it does not, have the vehicle
serviced by your dealer.
The light should go out once the
engine starts. If it stays on,
or comes on while driving, there
could be a problem with the
charging system. A charging system
message in the Driver Information
Center (DIC) can also appear. See
Battery Voltage and Charging
Messages on page 5‑38
for more
information. This light could indicate
that there are problems with a
generator drive belt, or that there is
an electrical problem. Have it
checked right away. If the vehicle
must be driven a short distance with
the light on, turn off accessories,
such as the radio and air
conditioner.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.

Black plate (23,1)GMC Yukon/Yukon XL Owner Manual - 2012
Instruments and Controls 5-23
Emissions Inspection and
Maintenance Programs
Some local governments may have
programs to inspect the on-vehicle
emission control equipment. For the
inspection, the emission system test
equipment is connected to the
vehicle’s Data Link
Connector (DLC).
The DLC is under the instrument
panel to the left of the steering
wheel. See your dealer if assistance
is needed.
The vehicle may not pass
inspection if:
.The malfunction indicator lamp is
on with the engine running, or if
the light does not come on when
the ignition is turned to ON/RUNwhile the engine is off. See your
dealer for assistance in verifying
proper operation of the
malfunction indicator lamp.
.The OBD II (On-Board
Diagnostics) system determines
that critical emission control
systems have not been
completely diagnosed. The
vehicle would be considered not
ready for inspection. This can
happen if the 12-volt battery has
recently been replaced or run
down. The diagnostic system is
designed to evaluate critical
emission control systems during
normal driving. This can take
several days of routine driving.
If this has been done and the
vehicle still does not pass the
inspection for lack of OBD II
system readiness, your dealer
can prepare the vehicle for
inspection.
Brake System Warning
Light
With the ignition on, the brake
system warning light comes on
when the parking brake is set. If the
vehicle is driven with the parking
brake engaged, a chime sounds
when the vehicle speed is greater
than 8 km/h (5 mph).
The vehicle brake system consists
of two hydraulic circuits. If one
circuit is not working, the remaining
circuit can still work to stop the
vehicle. For normal braking
performance, both circuits need to
be working.
If the warning light comes on and a
chime sounds there could be a
brake problem. Have the brake
system inspected right away.

Black plate (24,1)GMC Yukon/Yukon XL Owner Manual - 2012
5-24 Instruments and Controls
This light can also come on due to
low brake fluid. SeeBrake Fluid on
page 10‑27 for more information.
MetricEnglish
This light comes on briefly when the
ignition key is turned to ON/RUN.
If it does not come on then, have it
fixed so it is ready to warn if there is
a problem.
{WARNING
The brake system might not be
working properly if the brake
system warning light is on.
Driving with the brake system
warning light on can lead to a
crash. If the light is still on after
the vehicle has been pulled off
the road and carefully stopped,
have the vehicle towed for
service.
If the light comes on while driving,
pull off the road and stop carefully.
The pedal might be harder to push
or might go closer to the floor. It can
take longer to stop. If the light is still
on, have the vehicle towed for
service. See Towing the Vehicle on
page 10‑93.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
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.

Black plate (25,1)GMC Yukon/Yukon XL Owner Manual - 2012
Instruments and Controls 5-25
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.
SeeBrake System Warning Light on
page 5‑23.
For vehicles with a Driver
Information Center (DIC), see Brake
System Messages on page 5‑38 for
all brake‐related DIC messages.
If the vehicle is a hybrid, see the
hybrid supplement 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 9‑36.
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 9‑46, and Ride Control System
Messages on page 5‑43 for more
information.

Black plate (27,1)GMC Yukon/Yukon XL Owner Manual - 2012
Instruments and Controls 5-27
Engine Oil Pressure Light
{WARNING
Do not keep driving if the oil
pressure is low. The engine can
become so hot that it catches fire.
Someone could be burned. Check
the oil as soon as possible and
have the vehicle serviced.
Notice: Lack of proper engine oil
maintenance can damage the
engine. The repairs would not be
covered by the vehicle warranty.
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 come 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 5‑41 for more
information. When fuel is added this
light and message should go off.
If they do 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.

Black plate (29,1)GMC Yukon/Yukon XL Owner Manual - 2012
Instruments and Controls 5-29
Information Displays
Driver Information
Center (DIC)
Your vehicle has a Driver
Information Center (DIC).
The DIC displays information about
your vehicle. It also displays
warning messages if a system
problem is detected.
All messages will appear in the
DIC display located below the
tachometer in the instrument panel
cluster.
The DIC comes on when the ignition
is on. After a short delay, the DIC
will display the information that was
last displayed before the engine
was turned off.The DIC has different displays
which can be accessed by pressing
the DIC buttons located on the
instrument panel, next to the
steering wheel. If the vehicle does
not have DIC buttons, the trip
odometer reset stem can be used to
access some of the menu items.
The DIC displays trip, fuel, and
vehicle system information, and
warning messages if a system
problem is detected.
The DIC also allows some features
to be customized. See
Vehicle
Personalization (With DIC Buttons)
on page 5‑47 for more information. DIC Buttons
The buttons are the trip/fuel, vehicle
information, customization, and set/
reset buttons. The button functions
are detailed in the following pages.
3(Trip/Fuel):
Press to display
the odometer, trip odometer, fuel
range, average economy, fuel
used, timer, instantaneous
economy and Active Fuel
Management™ indicator, and
transmission temperature.

Black plate (38,1)GMC Yukon/Yukon XL Owner Manual - 2012
5-38 Instruments and Controls
Battery Voltage and
Charging Messages
BATTERY LOW START
VEHICLE
When the vehicle’s battery is
severely discharged, this message
will display and four chimes will
sound. Start the vehicle
immediately. If the vehicle is not
started and the battery continues to
discharge, the climate controls,
heated seats, and audio systems
will shut off and the vehicle may
require a jump start. These systems
will function again after the vehicle
is started.
SERVICE BATTERY
CHARGING SYSTEM
On some vehicles, this message
displays if there is a problem with
the battery charging system. Under
certain conditions, the charging
system light may also turn on in the
instrument panel cluster. See
Charging System Light on
page 5‑20. Driving with this problem could drain the battery. Turn off all
unnecessary accessories. Have the
electrical system checked as soon
as possible. See your dealer.
Brake System Messages
SERVICE BRAKE SYSTEM
This message displays along with
the brake system warning light if
there is a problem with the brake
system. See
Brake System Warning
Light on page 5‑23. If this message
appears, stop as soon as possible
and turn off the vehicle. Restart the
vehicle and check for the message
on the DIC display. If the message
is still displayed or appears again
when you begin driving, the brake
system needs service as soon as
possible. See your dealer.
SERVICE BRAKES SOON
This message displays if there is a
problem with the brake system.
If this message appears, stop as
soon as possible and turn off the
vehicle. Restart the vehicle and check for the message on the DIC
display. If the message is still
displayed or appears again when
you begin driving, the brake system
needs service. See your dealer.
SERVICE TRAILER BRAKE
SYSTEM
On vehicles with the Integrated
Trailer Brake Control (ITBC) system,
this message displays and a chime
sounds when there is a problem
with the ITBC system.
When this message displays, power
is no longer available to the trailer
brakes.
As soon as it is safe to do so,
carefully pull your vehicle over to
the side of the road and turn the
ignition off. Check the wiring
connection to the trailer and turn the
ignition back on. If this message still
displays, either your vehicle or the
trailer needs service. See your
dealer.