2015 GMC YUKON DENALI engine overheat

Black plate (15,1)GMC 2015i Yukon Denali/Yukon XL Denali Owner Manual (GMNA-
Localizing-U.S./Canada/Mexico-8431504) - 2015 - CRC - 7/30/14
Vehicle Care 10-15
{Caution
This vehicle has a specific
coolant fill procedure. Failure to
follow this procedure could cause
the engine to overheat and be
severely damaged.
{Warning
Steam and scalding liquids from a
hot cooling system can blow out
and burn you badly. Never turn
the cap when the cooling system,
including the surge tank pressure
cap, is hot. Wait for the cooling
system and surge tank pressure
cap to cool.
If no coolant is visible in the surge
tank, add coolant.
1. Remove the coolant surge tank pressure cap when the cooling
system, including the coolant
surge tank pressure cap and
upper radiator hose, is no
longer hot.
Turn the pressure cap slowly
counterclockwise about one full
turn. If a hiss is heard, wait for
that to stop. A hiss means there
is still some pressure left.
2. Keep turning the pressure cap slowly, and remove it.
3. Fill the coolant surge tank with the proper mixture to the FULL
COLD mark. 4. With the coolant surge tank
pressure cap off, start the
engine and let it run until the
engine coolant temperature
gauge indicates approximately
90°C (195°F).
By this time, the coolant level
inside the coolant surge tank
may be lower. If the level is
lower, add more of the proper
mixture to the coolant surge tank
until the level reaches the FULL
COLD mark.
5. Replace the pressure cap tightly.
6. Verify coolant level after the engine is shut off and the
coolant is cold. If necessary,
repeat coolant fill procedure
Steps 1–6.

Black plate (16,1)GMC 2015i Yukon Denali/Yukon XL Denali Owner Manual (GMNA-
Localizing-U.S./Canada/Mexico-8431504) - 2015 - CRC - 7/30/14
10-16 Vehicle Care
{Caution
If the pressure cap is not tightly
installed, coolant loss and
possible engine damage may
occur. Be sure the cap is properly
and tightly secured.
Engine Overheating
{Caution
Running the engine without
coolant may cause damage or a
fire. Vehicle damage would not be
covered by the vehicle warranty.
The vehicle has several indicators
to warn of engine overheating.
There is a coolant temperature
gauge in the vehicle's instrument
cluster. See Engine Coolant
Temperature Gauge on page 5-15. 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 5-40
andEngine Power
Messages on page 5-41.
If the decision is made not to lift the
hood when this warning appears,
get service help right away.
If the decision is made to lift the
hood, make sure the vehicle is
parked on a level surface.
Check to see if the engine cooling
fan(s) are running. If the engine is
overheating, the fans should be
running. If they are not, do not
continue to run the engine and have
the vehicle serviced.
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. Just turn it
off and get everyone away from
the vehicle until it cools down.
Wait until there is no sign of
steam or coolant before you open
the hood.
If you keep driving when the
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.

Black plate (17,1)GMC 2015i Yukon Denali/Yukon XL Denali Owner Manual (GMNA-
Localizing-U.S./Canada/Mexico-8431504) - 2015 - CRC - 7/30/14
Vehicle Care 10-17
If No Steam is Coming from
the Engine Compartment
The ENGINE OVERHEATED STOP
ENGINE or the ENGINE
OVERHEATED IDLE ENGINE
message, along with a low coolant
condition, can indicate a serious
problem.
If there is an engine overheat
warning, but no steam is seen or
heard, the problem may not be too
serious. Sometimes the engine can
get a little too hot when the vehicle:
.Climbs a long hill on a hot day.
.Stops after high-speed driving.
.Idles for long periods in traffic.
.Tows a trailer; seeTrailer Towing
on page 9-73.
If the ENGINE OVERHEATED
STOP ENGINE or the ENGINE
OVERHEATED IDLE ENGINE
message appears with no sign of
steam, try this for a minute or so:
1. Turn the air conditioning off. 2. Turn the heater on to the highest
temperature and to the highest
fan speed. Open the windows as
necessary.
3. When it is safe to do so, pull off the road, shift to P (Park) or
N (Neutral), and let the
engine idle.
If the temperature overheat gauge is
no longer in the overheat zone or an
overheat warning no longer
displays, the vehicle can be driven.
Continue to drive the vehicle slowly
for about 10 minutes. Keep a safe
vehicle distance from the vehicle in
front. If the warning does not come
back on, continue to drive normally
and have the cooling system
checked for proper fill and function.
If the warning continues, pull over,
stop, and park the vehicle
right away.
If there is still no sign of steam and
the vehicle is equipped with an
engine driven cooling fan, push
down the accelerator until the
engine speed is about twice as fast as normal idle speed for at least
five minutes while the vehicle is
parked. If the warning is still there,
turn off the engine and get everyone
out of the vehicle until it cools down.
If there is no sign of steam, idle the
engine for five minutes while
parked. If the warning is still
displayed, turn off the engine until it
cools down.
Engine Fan
If the vehicle has electric cooling
fans, the fans may be heard
spinning at low speed during most
everyday driving. The fans may turn
off if no cooling is required. Under
heavy vehicle loading, trailer towing,
high outside temperatures,
or operation of the air conditioning
system, the fans may change to
high speed and an increase in fan
noise may be heard. This is normal
and indicates that the cooling
system is functioning properly. The

Black plate (4,1)GMC 2015i Yukon Denali/Yukon XL Denali Owner Manual (GMNA-
Localizing-U.S./Canada/Mexico-8431504) - 2015 - CRC - 7/30/14
i-4 INDEX
Driving (cont'd)Vehicle Load Limits . . . . . . . . . . . 9-15
Wet Roads . . . . . . . . . . . . . . . . . . . 9-10
Winter . . . . . . . . . . . . . . . . . . . . . . . . 9-12
Dual Automatic Climate Control System . . . . . . . . . . . . . . . . 8-1
E
Electrical Equipment,Add-On . . . . . . . . . . . . . . . . . . . . . . 9-84
Electrical System
Engine CompartmentFuse Block . . . . . . . . . . . . . . . . 10-31
Fuses . . . . . . . . . . . . . . . . . . . . . . 10-31
Instrument Panel Fuse Block . . . . . . . . . 10-34, 10-37
Overload . . . . . . . . . . . . . . . . . . . 10-30
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . 10-40
Emergency
OnStar
®. . . . . . . . . . . . . . . . . . . . . . 14-2
Engine Air Cleaner/Filter . . . . . . . . . . . 10-10
Check and Service EngineSoon Light . . . . . . . . . . . . . . . . . . 5-20
Compartment Overview . . . . . . . 10-5 Engine (cont'd)
Coolant . . . . . . . . . . . . . . . . . . . . . 10-13
Coolant Temperature
Gauge . . . . . . . . . . . . . . . . . . . . . . 5-15
Coolant Temperature Warning Light . . . . . . . . . . . . . . . 5-26
Cooling System . . . . . . . . . . . . . 10-12
Cooling System Messages . . . 5-40
Drive Belt Routing . . . . . . . . . . . . 12-4
Exhaust . . . . . . . . . . . . . . . . . . . . . . 9-28
Fan . . . . . . . . . . . . . . . . . . . . . . . . . 10-17
Heater . . . . . . . . . . . . . . . . . . . . . . . . 9-24
Oil Life System . . . . . . . . . . . . . . . 10-9
Oil Messages . . . . . . . . . . . . . . . . . 5-40
Oil Pressure Gauge . . . . . . . . . . 5-14
Overheating . . . . . . . . . . . . . . . . 10-16
Power Messages . . . . . . . . . . . . . 5-41
Pressure Light . . . . . . . . . . . . . . . . 5-27
Running While Parked . . . . . . . . 9-29
Starting . . . . . . . . . . . . . . . . . . . . . . . 9-22
Entry Lighting . . . . . . . . . . . . . . . . . . . 6-7
Equipment, Towing . . . . . . . . . . . . 9-77
Event Data Recorders . . . . . . . . 13-14
Exit Lighting . . . . . . . . . . . . . . . . . . . . 6-8
Extender, Safety Belt . . . . . . . . . . 3-24
Exterior Lamp Controls . . . . . . . . . 6-1
Exterior Lamps Off Reminder . . . 6-2
F
Fan Engine . . . . . . . . . . . . . . . . . . . . . . 10-17
Features Memory . . . . . . . . . . . . . . . . . . . . . . . . 1-8
Filter, Engine Air Cleaner . . . . . . . . . 10-10
Flash-to-Pass . . . . . . . . . . . . . . . . . . . 6-3
Flashers, Hazard Warning . . . . . . 6-4
Flat Tire . . . . . . . . . . . . . . . . . . . . . . 10-62 Changing . . . . . . . . . . . . . . . . . . . 10-64
Floor Mats . . . . . . . . . . . . . . . . . . . . 10-89
Fluid Automatic Transmission . . . . 10-10
Brakes . . . . . . . . . . . . . . . . . . . . . . 10-19
Four-Wheel DriveTransfer Case . . . . . . . . . . . . . . . 9-35
Washer . . . . . . . . . . . . . . . . . . . . . 10-18
Fog Lamps . . . . . . . . . . . . . . . . . . . . . 6-5 Bulb Replacement . . . . . . . . . . 10-27
Forward Collision Alert (FCA) System . . . . . . . . . . . . . . . . 9-58
Four-Wheel Drive . . . . . . . 9-35, 10-21
Four-Wheel-Drive Light . . . . . . . . 5-24
Frequency Statement Radio . . . . . . . . . . . . . . . . . . . . . . . 13-12

Black plate (8,1)GMC 2015i Yukon Denali/Yukon XL Denali Owner Manual (GMNA-
Localizing-U.S./Canada/Mexico-8431504) - 2015 - CRC - 7/30/14
i-8 INDEX
Messages (cont'd)Transmission . . . . . . . . . . . . . . . . . 5-47
Vehicle . . . . . . . . . . . . . . . . . . . . . . . 5-37
Vehicle Reminder . . . . . . . . . . . . . 5-49
Washer Fluid . . . . . . . . . . . . . . . . . 5-50
Mirror Child-View . . . . . . . . . . . . . . . . . . . . 2-25
Mirrors Automatic Dimming . . . . . . . . . . . 2-23
Automatic Dimming
Rearview . . . . . . . . . . . . . . . . . . . . 2-24
Blind Spot . . . . . . . . . . . . . . . . . . . . 2-23
Convex . . . . . . . . . . . . . . . . . . . . . . . 2-22
Heated . . . . . . . . . . . . . . . . . . . . . . . 2-22
Power . . . . . . . . . . . . . . . . . . . . . . . . 2-22
Tilt in Reverse . . . . . . . . . . . . . . . . 2-24
Mirrors, Interior Rearview . . . . . . 2-24
Monitor System, Tire Pressure . . . . . . . . . . . . . . . . . . . . 10-50
N
NavigationOnStar®. . . . . . . . . . . . . . . . . . . . . . 14-3
Net, Convenience . . . . . . . . . . . . . . 4-3
New Vehicle Break-In . . . . . . . . . . 9-19
Noise Control System . . . . . . . . 10-23
O
Object Detection System Messages . . . . . . . . . . . . . . . . . . . . 5-42
Odometer . . . . . . . . . . . . . . . . . . . . . . 5-13 Trip . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-13
Off-Road . . . . . . . . . . . . . . . . . . . . . . . 9-6 Driving . . . . . . . . . . . . . . . . . . . . . . . . . 9-6
Recovery . . . . . . . . . . . . . . . . . . . . . . 9-5
Oil Engine . . . . . . . . . . . . . . . . . . . . . . . . 10-6
Engine Oil Life System . . . . . . . 10-9
Engine Oil PressureGauge . . . . . . . . . . . . . . . . . . . . . . 5-14
Messages . . . . . . . . . . . . . . . . . . . . 5-40
Pressure Light . . . . . . . . . . . . . . . . 5-27
Older Children, Restraints . . . . . 3-39
Online Owner Center . . . . . . . . . . 13-4
OnStar . . . . . . . . . . . . . . . . . . . . . . . 13-15
OnStar
®
System, In Brief . . . . . . . . . . . . . . 1-23
OnStar®Additional
Information . . . . . . . . . . . . . . . . . . . 14-6
OnStar
®Connections . . . . . . . . . . 14-4
OnStar®Emergency . . . . . . . . . . . 14-2
OnStar®Navigation . . . . . . . . . . . . 14-3
OnStar®Overview . . . . . . . . . . . . . 14-1 OnStar
®Security . . . . . . . . . . . . . . 14-3
OnStar®Vehicle
Diagnostics . . . . . . . . . . . . . . . . . . 14-6
Ordering Service Publications . . . . . . . . .13-11
Outlets Power . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
Overheating, Engine . . . . . . . . . . 10-16
P
Park Shifting Into . . . . . . . . . . . . . . . . . . . 9-25
Shifting Out of . . . . . . . . . . . . . . . . 9-27
Parking Brake . . . . . . . . . . . . . . . . . . . . . . . . . 9-39
Brake and P (Park)Mechanism Check . . . . . . . . 10-25
Over Things That Burn . . . . . . . 9-27
Parking or Backing Assistance Systems . . . . . . . . . . 9-55
Passenger Airbag Status Indicator . . . . . . . . . . . . . . . . . . . . . 5-19
Passenger Compartment Air
Filter . . . . . . . . . . . . . . . . . . . . . . . . . . 8-7
Passenger Sensing System . . . 3-33