service indicator GMC YUKON 2012 User Guide

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 (41,1)GMC Yukon/Yukon XL Owner Manual - 2012
Instruments and Controls 5-41
cause of the low oil pressure is
corrected. SeeEngine Oil on
page 10‑8 for more information.
This message displays if low oil
pressure levels occur. Stop the
vehicle as soon as safely possible
and do not operate it until the cause
of the low oil pressure has been
corrected. Check the oil as soon as
possible and have the vehicle
serviced by your dealer. See Engine
Oil on page 10‑8.
Engine Power Messages
ENGINE POWER IS REDUCED
This message displays and a chime
sounds when the cooling system
temperature gets too hot and the
engine further enters the engine
coolant protection mode. See
Engine Overheating on page 10‑21
for further information.
This message also displays when
the engine power is reduced.
Reduced engine power can affect
the vehicle's ability to accelerate. If this message is on, but there
is no reduction in performance,
proceed to your destination. The
performance may 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
sounds if the fuel level is low. Refuel
as soon as possible. See
Fuel
Gauge on page 5‑14 andFuel on
page 9‑61 for more information.
TIGHTEN GAS CAP
This message may display along
with the check engine light on the
instrument panel cluster if the fuel cap is not tightened properly. See
Malfunction Indicator Lamp on
page 5‑21. Reinstall the fuel cap
fully. See
Filling the Tank on
page 9‑65. 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.

Black plate (7,1)GMC Yukon/Yukon XL Owner Manual - 2012
Lighting 6-7
#(Fog Lamps):Press to turn the
fog lamps on or off. A light will come
on in the instrument panel cluster.
When the fog lamps are turned on,
the parking lamps automatically
turn on.
When the headlamps are changed
to high beam, the fog lamps also go
off. When the high-beam headlamps
are turned off, the fog lamps will
come on again.
Some localities have laws that
require the headlamps to be on with
the fog lamps.Auxiliary
Roof-Mounted Lamp
If the vehicle has this feature, this
button includes wiring provisions for
a dealer or a qualified service center
to install an auxiliary roof lamp.
This button is located on the
overhead console.
When the wiring is connected to an
auxiliary roof‐mounted lamp,
pressing the bottom of the button
will activate the lamp and illuminate
an indicator light at the bottom of
this button. Pressing the top of the
button will turn off the roof‐mounted
lamp and indicator. The emergency roof lamp circuit is
fused at 30 amps, so the total
current draw of the attached lamps
should be less than this value. The
attachment points for the roof lamp
circuits are two blunt cut wires
located above the overhead
console, a dark green switched
power wire and a black ground wire.
For more information on roof mount
emergency lamp installation, please
visit the GM Upfitter website at
www.gmupfitter.com or contact your
dealer.
If the vehicle has this button, the
vehicle may have the snow plow
prep package. For further
information, see
Adding a Snow
Plow or Similar Equipment on
page 9‑86.

Black plate (23,1)GMC Yukon/Yukon XL Owner Manual - 2012
Driving and Operating 9-23
If the vehicle must be shut off in an
emergency:
1. Brake using a firm and steadypressure. Do not pump the
brakes repeatedly. This may
deplete power assist, requiring
increased brake pedal force.
2. Shift the vehicle to N (Neutral). This can be done while the
vehicle is moving. After shifting
to N (Neutral), firmly apply the
brakes and steer the vehicle to a
safe location.
3. Come to a complete stop, shift to P (Park), and turn the ignition
to LOCK/OFF. On vehicles with
an automatic transmission, the
shift lever must be in P (Park) to
turn the ignition switch to the
LOCK/OFF position.
4. Set the parking brake. See Parking Brake on page 9‑45.{WARNING
Turning off the vehicle while
moving may cause loss of power
assist in the brake and steering
systems and disable the airbags.
While driving, only shut the
vehicle off in an emergency.
If the vehicle cannot be pulled over,
and must be shut off while driving,
turn the ignition to ACC/
ACCESSORY.
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
doesn't 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.

Black plate (29,1)GMC Yukon/Yukon XL Owner Manual - 2012
Driving and Operating 9-29
.Prevent movement of the shift
lever out of P (Park), unless the
ignition is in ON/RUN or ACC/
ACCESSORY and the regular
brake pedal is applied.
The shift lock release is always
functional except in the case of an
uncharged or low voltage (less than
9 volt) battery.
If the vehicle has an uncharged
battery or a battery with low voltage,
try charging or jump starting the
battery. See Jump Starting on
page 10‑88 for more information.
To shift out of P (Park) use the
following:
1. Apply the brake pedal.
2. Move the shift lever to the desired position. If you still are unable to shift out of
P (Park):
1. Ease the pressure on the shift
lever.
2. While holding down the brake pedal, press the shift lever all
the way into P (Park).
3. Move the shift lever to the desired position.
If you are still having a problem
shifting, then have the vehicle
serviced soon.
Parking over Things
That Burn
{WARNING
Things that can burn could touch
hot exhaust parts under the
vehicle and ignite. Do not park
over papers, leaves, dry grass,
or other things that can burn.
Active Fuel Management®
Vehicles with V8 engines may have
Active Fuel Management™. This
system allows the engine to operate
on either all or half of its cylinders,
depending on the driving conditions.
When less power is required, such
as cruising at a constant vehicle
speed, the system will operate in
the half cylinder mode, allowing the
vehicle to achieve better fuel
economy. When greater power
demands are required, such as
accelerating from a stop, passing,
or merging onto a freeway, the
system will maintain full-cylinder
operation.
If the vehicle has an Active Fuel
Management™ indicator, seeDriver
Information Center (DIC) on
page 5‑29 for more information on
using this display.

Black plate (38,1)GMC Yukon/Yukon XL Owner Manual - 2012
9-38 Driving and Operating
If the lights do not come on, you
should take the vehicle to your
dealer for service. An indicator light
will flash while shifting. It will stay on
when the shift is completed. 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, and the
vehicle's power is sent 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 you need extra traction, such
as on snowy or icy roads or in most
off-road situations. This setting also
engages your 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.
The vehicle has StabiliTrak. Shifting
into Four-Wheel Drive Low will turn
Traction Control and StabiliTrak off.
See StabiliTrak
®System on
page 9‑46.
{WARNING
Shifting the transfer case to
N (Neutral) can cause the vehicle
to roll even if the transmission is
in P (Park). You or someone else
could be seriously injured. Be
sure to set the parking brake
before placing the transfer case in
N (Neutral). See Parking Brake on
page 9‑45.
N (Neutral): Shift the vehicle's
transfer case to N (Neutral) only
when towing the vehicle. See
Recreational Vehicle Towing on
page 10‑93 orTowing the Vehicle
on page 10‑93 for more information.
If the SERVICE 4 WHEEL DRIVE
message stays on, you should take
the vehicle to your dealer for
service. See “SERVICE 4 WHEEL
DRIVE” message under
Transmission Messages on
page 5‑45.

Black plate (42,1)GMC Yukon/Yukon XL Owner Manual - 2012
9-42 Driving and Operating
Four-Wheel Drive
(Single Speed Automatic
Transfer Case)
If the vehicle has four-wheel drive,
you can send the engine's driving
power to all four wheels for extra
traction. Read the following before
using four-wheel drive.
Notice:Driving on clean, dry
pavement in Four-Wheel Drive
High for an extended period of
time may cause premature wear
on the vehicle's powertrain. Do
not drive on clean, dry pavement
in Four-Wheel Drive High for
extended periods of time.
While driving on clean dry pavement
and during tight turns, you may
experience a vibration in the
steering system.
Front Axle
The front axle engages and
disengages automatically when you
shift the transfer case. Some delay
for the axle to engage or disengage
is normal.
Automatic Transfer Case
The transfer case knob is located to
the left of the instrument panel
cluster.
Use this dial to shift into and out of
four-wheel drive. The vehicle has Four-Wheel Drive
with StabiliTrak
®. For information on
StabiliTrak, see StabiliTrak®System
on page 9‑46.
You can choose among three
driving settings:
Indicator lights in the switch show
you which setting you are in. The
indicator lights will come on briefly
when you turn on the ignition and
the last chosen setting 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. It will stay on
when the shift is completed. 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 (43,1)GMC Yukon/Yukon XL Owner Manual - 2012
Driving and Operating 9-43
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, and the
vehicle's power is sent 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 you need extra traction, 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. Service Four‐Wheel Drive
If the SERVICE 4 WHEEL DRIVE
message stays on, you should take
the vehicle to your dealer for
service. See
“SERVICE 4 WHEEL
DRIVE” message under
Transmission Messages on
page 5‑45.
Shifting Into Four-Wheel Drive
High or AUTO (Automatic
Four-Wheel Drive)
Turn the knob to the Four-Wheel
Drive High or AUTO position. This
can be done at any speed. The
indicator light will flash while
shifting. It will remain on when the
shift is completed. Shifting Into Two-Wheel
Drive High
Turn the knob to the Two-Wheel
Drive High position. This can be
done at any speed. The indicator
light will flash while shifting. It will
remain on when the shift is
completed.
Excessively shifting the transfer
case into or out of the different
modes may cause the transfer case
to enter the shift protection mode.
This will protect the transfer case
from possible damage and will only
allow the transfer case to respond to
one shift per 10 seconds. The
transfer case may stay in this mode
for up to three minutes.

Black plate (54,1)GMC Yukon/Yukon XL Owner Manual - 2012
9-54 Driving and Operating
Turning the System On and Off
Press this button, located next to
the radio, to disable URPA.
The indicator light comes on and
PARK ASSIST OFF displays on the
Driver Information Center (DIC).
SeeObject Detection System
Messages on page 5‑42.
When the System Does Not
Seem to Work Properly
The following messages may be
displayed on the DIC:
SERVICE PARK ASSIST: this
message occurs, take the vehicle to
your dealer for repair. PARK ASSIST OFF:
This message
occurs if the driver disables the
system or if the vehicle is driven
above 8 km/h (5 mph) in
R (Reverse).
PARK ASST BLOCKED SEE
OWNERS MANUAL: This
message can occur under the
following conditions:
.The ultrasonic sensors are not
clean. Keep the rear bumper
free of mud, dirt, snow, ice,
slush, and frost. The message
may not clear until frost or ice
has melted all around and inside
the sensor.
.A trailer is attached to the
vehicle, or a bicycle or an object
hanging out of the liftgate during
the current or last drive cycle.
URPA will return to normal
operation after it is determined
the object is removed. This
could take a few drive cycles.
.A tow bar is attached to the
vehicle. Other conditions may affect system
performance, such as vibrations
from a jackhammer or the
compression of air brakes on a
very large truck.
Side Blind Zone
Alert (SBZA)
If available, the Side Blind Zone
Alert system is a lane changing aid
that assists drivers with avoiding
crashes that occur with vehicles in
the side blind zones.
{WARNING
SBZA does not detect vehicles
rapidly approaching outside of the
side blind zones, pedestrians,
bicyclists, or animals. Failure to
use proper care when changing
lanes may result in injury, death,
or vehicle damage. Always check
for other vehicles and use the
turn signals when changing lanes.

Black plate (62,1)GMC Yukon/Yukon XL Owner Manual - 2012
9-62 Driving and Operating
Vehicles that have a FlexFuel badge
and a yellow fuel cap can use either
unleaded gasoline or ethanol fuel
containing up to 85% ethanol (E85).
SeeFuel E85 (85% Ethanol) on
page 9‑64. For all other vehicles,
use only the unleaded gasoline
described under Recommended
Fuel on page 9‑62.
Recommended Fuel
Use regular unleaded gasoline with
a posted octane rating of 87 or
higher. If the octane rating is less
than 87, an audible knocking noise,
commonly referred to as spark
knock, might be heard when driving.
If this occurs, use a gasoline rated
at 87 octane or higher as soon as
possible. If heavy knocking is heard
when using gasoline rated at
87 octane or higher, the engine
needs service.
Gasoline Specifications
(U.S. and Canada Only)
At a minimum, gasoline should
meet ASTM specification
D 4814 in the United States or
CAN/CGSB‐3.5 or 3.511 in Canada.
Some gasolines contain an
octane-enhancing additive called
methylcyclopentadienyl manganese
tricarbonyl (MMT). We recommend
against the use of gasolines
containing MMT. See Fuel Additives
on page 9‑63 for additional
information.
California Fuel
Requirements
If the vehicle is certified to meet
California Emissions Standards, it is
designed to operate on fuels that
meet California specifications. See
the underhood emission control
label. If this fuel is not available in
states adopting California Emissions
Standards, the vehicle will operate satisfactorily on fuels meeting
federal specifications, but emission
control system performance might
be affected. The malfunction
indicator lamp could turn on and the
vehicle might fail a smog‐check test.
See
Malfunction Indicator Lamp on
page 5‑21. If this occurs, return to
your authorized dealer for diagnosis.
If it is determined that the condition
is caused by the type of fuel used,
repairs might not be covered by the
vehicle warranty.
Fuels in Foreign
Countries
Never use leaded gasoline or any
other fuel not recommended in the
previous text on fuel. Costly repairs
caused by use of improper fuel
would not be covered by the vehicle
warranty.
To check the fuel availability, ask an
auto club, or contact a major oil
company that does business in the
country where you will be driving.