Page 275 of 439

Black plate (4,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-4 Vehicle Care This vehicle has an airbag system.
Before attempting to do your own
service work, see Servicing the
Airbag-Equipped Vehicle on
page 3-28 .
Keep a record with all parts receipts
and list the mileage and the date of
any service work performed. See
Maintenance Records on
page 11-16 .
{ CautionEven small amounts of
contamination can cause damage
to vehicle systems. Do not allow
contaminants to contact the fluids,
reservoir caps, or dipsticks. Hood To open the hood:
1. Pull the handle with this symbol
on it. It is inside the vehicle
under the steering wheel. 2. Go to the front of the vehicle to
find the secondary hood release.
The handle is under the front
edge of the hood near the
center. Push the handle to the
right and at the same time raise
the hood.
Before closing the hood, be sure all
the filler caps are on properly. Then
bring the hood from full open to
within 15 cm (6 in) from the closed
position, pause, and push the front
center of the hood with a swift, firm
motion to fully close the hood.
Page 293 of 439

Black plate (22,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-22 Vehicle Care In addition, there are ENGINE
OVERHEATED STOP ENGINE,
ENGINE OVERHEATED IDLE
ENGINE, and ENGINE POWER IS
REDUCED messages in the Driver
Information Center (DIC). See
Engine Cooling System Messages
on page 5-33 and Engine Power
Messages on page 5-34 .
If the decision is made not to lift the
hood when this warning appears,
get service help right away. See
Roadside Assistance Program on
page 13-5 .
If the decision is made to lift the
hood, make sure the vehicle is
parked on a level surface.
Then check to see if the engine
cooling fan is running. If the engine
is overheating, the fan should be
running. If it is not, do not continue
to run the engine and have the
vehicle serviced. { CautionRunning the engine without
coolant may cause damage or a
fire. Vehicle damage would not be
covered by the vehicle warranty.
See Overheated Engine
Protection Operating Mode on
page 10-23 for information on
driving to a safe place in an
emergency.
If Steam is Coming from the
Engine Compartment
{ Warning
Steam from an overheated engine
can burn you badly, even if you
just open the hood. Stay away
from the engine if you see or hear
steam coming from it. Turn it off
and get everyone away from the
vehicle until it cools down. Wait
(Continued) Warning (Continued) until there is no sign of steam or
coolant before you open
the hood.
If you keep driving when the
vehicles engine is overheated,
the liquids in it can catch fire. You
or others could be badly burned.
Stop the engine if it overheats,
and get out of the vehicle until the
engine is cool.
See Overheated Engine
Protection Operating Mode on
page 10-23 for information on
driving to a safe place in an
emergency.
Page 307 of 439

Black plate (36,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-36 Vehicle Care
Headlamp Aiming Headlamp aim has been preset and
should need no further adjustment.
If the vehicle is damaged in a crash,
the headlamp aim may be affected.
If adjustment to the headlamps is
necessary, see your dealer.
Bulb Replacement For the proper type of replacement
bulbs, see Replacement Bulbs on
page 10-40 .
For any bulb ‐ changing procedure
not listed in this section, contact
your dealer.
Halogen Bulbs
{ WarningHalogen bulbs have pressurized
gas inside and can burst if you
drop or scratch the bulb. You or
others could be injured. Be sure
to read and follow the instructions
on the bulb package.
LED Lighting This vehicle has several LED lamps.
For replacement of any LED lighting
assembly, contact your dealer. Headlamps, Front Turn
Signal, Sidemarker, and
Parking Lamps
Driver Side
1. Front Turn Signal/
Sidemarker/Parking Lamp
2. High/Low-Beam Headlamp
See your dealer for passenger side
replacement.
Headlamp
1. Open the hood.
Page 308 of 439

Black plate (37,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-372. Remove the headlamp bulb
assembly cover by turning it
counterclockwise.
3. Turn the bulb socket
counterclockwise to remove it
from the headlamp assembly
and pull it straight out.
4. Unplug the electrical connector
from the old bulb by releasing
the clip on the bulb socket.
Turn Signal/Sidemarker/
Parking Lamp 1. Open the hood.
2. If replacing a bulb on the
passenger side, remove the
engine air cleaner.
3. Turn the bulb socket
counterclockwise to remove it
from the headlamp assembly
and pull it straight out.
4. Remove the bulb by pulling it
straight out of the bulb socket. Fog Lamps To replace the front fog lamp bulb:
1. Locate the fog lamp under the
front bumper.
2. Disconnect the electrical
connector from the fog lamp bulb
assembly by pressing the
connector release.
3. Remove the bulb from the
housing by squeezing the two
release tabs and pulling it
straight out of the assembly. Taillamps, Turn Signal,
Stoplamps, and Back-Up
Lamps
Single Rear Wheel Lamp Shown,
Dual Rear Wheel Lamp Similar
1. Stoplamp/Taillamp/Turn
Signal Lamp
2. Back-Up Lamp
3. Sidemarker Lamp
To replace one of these bulbs:
1. Open the tailgate.
Page 359 of 439

Black plate (88,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-88 Vehicle Care begin that, especially in cold
weather, you may not be able to
get enough power from a single
battery in another vehicle to start
your diesel engine. If your
vehicle has more than one
battery, using the battery that is
closer to the starter will reduce
electrical resistance. This is
located on the passenger side,
in the rear of the engine
compartment.
3. Get the vehicles close enough
so the jumper cables can reach,
but be sure the vehicles are not
touching each other. If they are,
it could cause an unwanted
ground connection. You would
not be able to start your vehicle,
and the bad grounding could
damage the electrical systems.
To avoid the possibility of the
vehicles rolling, set the parking
brake firmly on both vehicles
involved in the jump start
procedure. Put the automatic
transmission in P (Park) or a
manual transmission in Neutral before setting the parking brake.
If you have a four-wheel-drive
vehicle, be sure the transfer
case is in a drive gear, not in
N (Neutral).
{ CautionIf any accessories are left on or
plugged in during the jump
starting procedure, they could be
damaged. The repairs would not
be covered by the vehicle
warranty. Whenever possible, turn
off or unplug all accessories on
either vehicle when jump starting.
4. Turn off the ignition on both
vehicles. Unplug unnecessary
accessories plugged into the
accessory power outlets. Turn
off the radio and all the lamps
that are not needed. This will
avoid sparks and help save both
batteries. And it could save the
radio! 5. Open the hood on the other
vehicle and locate the
positive (+) and negative ( − )
terminal locations on that
vehicle.
The positive (+) terminal is under
a red plastic cover at the positive
battery post. To uncover the
positive (+) terminal, open the
red plastic cover.
For more information on the
location of the remote
positive (+) and remote negative
( − ) terminals, see Engine
Compartment Overview on
page 10-5 .
{ Warning
An electric fan can start up even
when the engine is not running
and can injure you. Keep hands,
clothing and tools away from any
underhood electric fan.