2020 GMC YUKON engine overheat

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
298 Vehicle Care
What to Use
{Warning
Plain water, or other liquids such
as alcohol, can boil before the
proper coolant mixture will. With
plain water or the wrong mixture,
the engine could get too hot but
there would not be an overheat
warning. The engine could catch
fire and you or others could be
burned.
Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
coolant. This mixture:
. Gives freezing protection down
to−37 °C (−34 °F), outside
temperature .
Gives boiling protection up to
129 °C (265 °F), engine
temperature
. Protects against rust and
corrosion
. Will not damage aluminum parts
. Helps keep the proper engine
temperature
Caution
Do not use anything other than a
mix of DEX-COOL coolant that
meets GM Standard
GMW3420 and clean, drinkable
water. Anything else can cause
damage to the engine cooling
system and the vehicle, which
would not be covered by the
vehicle warranty.
Never dispose of engine coolant by
putting it in the trash, or by pouring
it on the ground, or into sewers,
streams, or bodies of water. Have
the coolant changed by an
authorized service center, familiar
with legal requirements regarding used coolant disposal. This will help
protect the environment and your
health.
Checking Coolant
The coolant surge tank is in the
engine compartment on the
passenger side of the vehicle. See
Engine Compartment Overview
0
286.
The vehicle must be on a level
surface when checking the coolant
level.
Check to see if coolant is visible in
the coolant surge tank. If the coolant
inside the coolant surge tank is

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
Vehicle Care 299
boiling, wait until it cools down. The
coolant level should be at or above
the full cold mark. If it is not, there
may be a leak in the cooling
system.
If coolant is visible but the coolant
level is not at or above the full cold
mark, see“How to Add Coolant to
the Coolant Surge Tank,” following.
How to Add Coolant to the
Coolant Surge Tank
{Warning
Spilling coolant on hot engine
parts can burn you. Coolant
contains ethylene glycol and it will
burn if the engine parts are hot
enough.
{Warning
Plain water, or other liquids such
as alcohol, can boil before the
proper coolant mixture will. With
(Continued)
Warning (Continued)
plain water or the wrong mixture,
the engine could get too hot but
there would not be an overheat
warning. The engine could catch
fire and you or others could be
burned.
{Warning
Steam and scalding liquids from a
hot cooling system are under
pressure. Turning the pressure
cap, even a little, can cause them
to come out at high speed and
you could be burned. Never turn
the cap when the cooling system,
including the pressure cap, is hot.
Wait for the cooling system and
pressure cap to cool.
Caution
Failure to follow the specific
coolant fill procedure could cause
the engine to overheat and could
cause system damage. If coolant
is not visible in the surge tank,
contact your dealer.
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.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
300 Vehicle Care
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.
Caution
If the pressure cap is not tightly
installed, coolant loss and engine
damage may occur. Be sure the
cap is properly and tightly
secured.
Engine Overheating
Caution
Do not run the engine if there is a
leak in the engine cooling system.
This can cause a loss of all
coolant and can damage the
system and vehicle. Have any
leaks fixed right away.
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 0131.
In addition, there are ENGINE
OVERHEATED STOP ENGINE,
ENGINE OVERHEATED IDLE
ENGINE, and ENGINE POWER IS
REDUCED messages in the Driver
Information Center (DIC).
If the decision is made not to lift the
hood when this warning appears,
get service help right away. See
Roadside Assistance Program
0 400.
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. Have the
vehicle serviced.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
Vehicle Care 301
If Steam is Coming from the
Engine Compartment
{Warning
Steam and scalding liquids from a
hot cooling system are under
pressure. Turning the pressure
cap, even a little, can cause them
to come out at high speed and
you could be burned. Never turn
the cap when the cooling system,
including the pressure cap, is hot.
Wait for the cooling system and
pressure cap to cool.
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; see Trailer Towing
0 264.
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 engine coolant temperature
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.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
Vehicle Care 315
Windshield Wipers
If the wiper motor overheats due to
heavy snow or ice, the windshield
wipers will stop until the motor cools
and will then restart.
Although the circuit is protected
from electrical overload, overload
due to heavy snow or ice may
cause wiper linkage damage.
Always clear ice and heavy snow
from the windshield before using the
windshield wipers.
If the overload is caused by an
electrical problem and not snow or
ice, be sure to get it fixed.
Fuses and Circuit
Breakers
The wiring circuits in the vehicle are
protected from short circuits by a
combination of fuses and circuit
breakers. This greatly reduces the
chance of damage caused by
electrical problems.
{Danger
Fuses and circuit breakers are
marked with their ampere rating.
Do not exceed the
specified amperage rating when
replacing fuses and circuit
breakers. Use of an oversized
fuse or circuit breaker can result
in a vehicle fire. You and others
could be seriously injured or
killed.
To check a fuse, look at the
silver-colored band inside the fuse.
If the band is broken or melted,
replace the fuse. Be sure to replace
a bad fuse with a new one of the
identical size and rating.
Fuses of the same amperage can
be temporarily borrowed from
another fuse location, if a fuse goes
out. Replace the fuse as soon as
possible.
Engine Compartment
Fuse Block
The engine compartment fuse block
is in the engine compartment, on
the driver side of the vehicle.
Lift the cover to access the fuse
block.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./Cana-
da/Mexico-13566587) - 2020 - CRC - 4/15/19
424 Index
DrivingAssistance Systems . . . . . . . . . . 245
Better Fuel Economy . . . . . . . . . 184
Characteristics and
Towing Tips . . . . . . . . . . . . . . . . . 259
Defensive . . . . . . . . . . . . . . . . . . . . . 185
Drunk . . . . . . . . . . . . . . . . . . . . . . . . . 185
Hill and Mountain Roads . . . . . . 193
If the Vehicle is Stuck . . . . . . . . . 195
Loss of Control . . . . . . . . . . . . . . . 187
Off-Road . . . . . . . . . . . . . . . . . . . . . 188
Off-Road Recovery . . . . . . . . . . . 187
Vehicle Load Limits . . . . . . . . . . . 196
Wet Roads . . . . . . . . . . . . . . . . . . . 193
Winter . . . . . . . . . . . . . . . . . . . . . . . . 194
Dual Automatic Climate
Control System . . . . . . . . . . . . . . . . 175
E
E85 or FlexFuel . . . . . . . . . . . . . . . . 255
Electrical Equipment,Add-On . . . . . . . . . . . . . . . . . . . . . . . 280
Electrical System Engine Compartment FuseBlock . . . . . . . . . . . . . . . . . . . . . . . . 315
Fuses and Circuit Breakers . . . 315
Instrument Panel Fuse
Block . . . . . . . . . . . . . . . . . . . 320, 323 Electrical System (cont'd)
Overload . . . . . . . . . . . . . . . . . . . . . 314
Rear Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 325
Emergency OnStar . . . . . . . . . . . . . . . . . . . . . . . .411
Engine Air Cleaner/Filter . . . . . . . . . . . . . 296
Check Light (MalfunctionIndicator) . . . . . . . . . . . . . . . . . . . . 136
Compartment Overview . . . . . . . 286
Coolant Temperature Gauge . . . . . . . . . . . . . . . . . . . . . . 131
Coolant Temperature
Warning Light . . . . . . . . . . . . . . . 141
Cooling System . . . . . . . . . . . . . . . 297
Drive Belt Routing . . . . . . . . . . . . 395
Exhaust . . . . . . . . . . . . . . . . . . . . . . 212
Fan . . . . . . . . . . . . . . . . . . . . . . . . . . . 302
Heater . . . . . . . . . . . . . . . . . . . . . . . . 207
Oil Life System . . . . . . . . . . . . . . . 291
Oil Pressure Gauge . . . . . . . . . . 130
Oil Pressure Light . . . . . . . . . . . . 142
Overheating . . . . . . . . . . . . . . . . . . 300
Power Messages . . . . . . . . . . . . . 151
Running While Parked . . . . . . . . 212
Starting . . . . . . . . . . . . . . . . . . . . . . . 206
Entry Lighting . . . . . . . . . . . . . . . . . . . 171 Equipment, Towing . . . . . . . . . . . . . 270
Event Data Recorders . . . . . . . . . . 408
Exit Lighting . . . . . . . . . . . . . . . . . . . . 171
Extended Parking . . . . . . . . . . . . . . . 211
Extender, Seat Belt . . . . . . . . . . . . . . 71
Exterior Lamp Controls . . . . . . . . . 164
Exterior Lamps Off Reminder . . . 166
Exterior Lighting Battery
Saver . . . . . . . . . . . . . . . . . . . . . . . . . 173
F
FanEngine . . . . . . . . . . . . . . . . . . . . . . . . 302
Filter, Engine Air Cleaner . . . . . . . . . . . 296
Flash-to-Pass . . . . . . . . . . . . . . . . . . . 167
Flashers, Hazard Warning . . . . . . 168
Flat Tire . . . . . . . . . . . . . . . . . . . . . . . . 347 Changing . . . . . . . . . . . . . . . . . . . . . 349
FlexFuel E85 . . . . . . . . . . . . . . . . . . . . . . . . . . . 255
Floor Console Storage . . . . . . . . . . 111
Floor Mats . . . . . . . . . . . . . . . . . . . . . . 375
Fluid AutomaticTransmission . . . . . . . . . . . 292, 295
Brakes . . . . . . . . . . . . . . . . . . . . . . . . 304

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./Cana-
da/Mexico-13566587) - 2020 - CRC - 4/15/19
428 Index
Monitor System, TirePressure . . . . . . . . . . . . . . . . . . . . . . 335
N
Navigation
Connected Services . . . . . . . . . . 418
Net, Convenience . . . . . . . . . . . . . . 112
New Vehicle Break-In . . . . . . . . . . . 201
Noise Control System . . . . . . . . . . 306
O
Odometer . . . . . . . . . . . . . . . . . . . . . . . 129 Trip . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
Off-Road . . . . . . . . . . . . . . . . . . . . . . . 188 Driving . . . . . . . . . . . . . . . . . . . . . . . . 188
Recovery . . . . . . . . . . . . . . . . . . . . . 187
Oil
Engine . . . . . . . . . . . . . . . . . . . . . . . . 289
Engine Oil Life System . . . . . . . 291
Engine Oil Pressure Gauge . . . 130
Pressure Light . . . . . . . . . . . . . . . . 142
Older Children, Restraints . . . . . . . 86
Online Owner Center . . . . . . . . . . . 399
OnStar . . . . . . . . . . . . . . . . . . . . . . . . . 409
OnStar Additional
Information . . . . . . . . . . . . . . . . . . . . 412
OnStar Emergency . . . . . . . . . . . . . 411
OnStar Overview . . . . . . . . . . . . . . . 410
OnStar Security . . . . . . . . . . . . . . . . 412 Operation
Fog Lamps . . . . . . . . . . . . . . . . . . . 169
Outlets Power . . . . . . . . . . . . . . . . . . . . . . . . 120
Overheating, Engine . . . . . . . . . . . . 300
Overview Instrument Panel . . . . . . . . . . . . . . . . 5
P
Park
Shifting Out of . . . . . . . . . . . . . . . . 210
Park Assist . . . . . . . . . . . . . . . . . . . . . 242
Parking
Brake . . . . . . . . . . . . . . . . . . . . . . . . . 225
Brake and P (Park)Mechanism Check . . . . . . . . . . 309
Extended . . . . . . . . . . . . . . . . . . . . . .211
Over Things That Burn . . . . . . . .211
Parking or Backing Assistance Systems . . . . . . . . . . 242
Passenger Airbag Status
Indicator . . . . . . . . . . . . . . . . . . . . . . 135
Passenger Compartment Air Filter . . . . . . . . . . . . . . . . . . . . . . . . . . 181
Passenger Sensing System . . . . . 80
Perchlorate Materials Requirements, California . . . . . . 283 Personalization
Vehicle . . . . . . . . . . . . . . . . . . . . . . . 152
Power Door Locks . . . . . . . . . . . . . . . . . . . . . 25
Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Outlets . . . . . . . . . . . . . . . . . . . . . . . 120
Protection, Battery . . . . . . . . . . . . 172
Retained Accessory (RAP) . . . 209
Seat Adjustment . . . . . . . . . . . . . . . . 48
Windows . . . . . . . . . . . . . . . . . . . . . . . 42
Power Assist Steps . . . . . . . . . . . . . . 32
Pregnancy, Using Seat Belts . . . . 70
Privacy
Vehicle Data Recording . . . . . . . 407
Program Courtesy Transportation . . . . . . 402
Prohibited Fuels . . . . . . . . . . . . . . . . 255
Proposition 65 Warning,
California . . . . . . . . . . . .282, 305, 360, Back Cover
Publication Ordering Information . . . . . . . . . . . . . . . . . . . . 405
R
Radio Frequency Statement . . . . 405
Reading Lamps . . . . . . . . . . . . . . . . . 171
Rear Axle . . . . . . . . . . . . . . . . . . . . . . . 306