heater GMC YUKON 2012 User Guide

Black plate (17,1)GMC Yukon/Yukon XL Owner Manual - 2012
Vehicle Care 10-17
{WARNING
An electric engine cooling fan
under the hood can start up even
when the engine is not running
and can cause injury. Keep
hands, clothing, and tools away
from any underhood electric fan.
{WARNING
Heater and radiator hoses, and
other engine parts, can be very
hot. Do not touch them. If you do,
you can be burned.(Continued)
WARNING (Continued)
Do not run the engine if there is a
leak. If you run the engine, it
could lose all coolant. That could
cause an engine fire, and you
could be burned. Get any leak
fixed before you drive the vehicle.
Notice: Using coolant other than
DEX-COOL
®can cause premature
engine, heater core, or radiator
corrosion. In addition, the engine
coolant could require changing
sooner, at 50 000 km (30,000 mi)
or 24 months, whichever occurs
first. Any repairs would not be
covered by the vehicle warranty.
Always use DEX-COOL
(silicate-free) coolant in the
vehicle.
Engine Coolant
The cooling system in the vehicle
is filled with DEX-COOL engine
coolant. This coolant is designed to
remain in the vehicle for 5 years or
240 000 km (150,000 mi), whichever
occurs first.
The following explains the cooling
system and how to check and add
coolant when it is low. If there is a
problem with engine overheating,
see Engine Overheating on
page 10‑21.

Black plate (18,1)GMC Yukon/Yukon XL Owner Manual - 2012
10-18 Vehicle Care
What to Use
{WARNING
Adding only plain water or some
other liquid to the cooling system
can be dangerous. Plain water
and other liquids, can boil before
the proper coolant mixture will.
The coolant warning system is set
for the proper coolant mixture.
With plain water or the wrong
mixture, the engine could get too
hot but you would not get the
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.Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
coolant. If using this mixture,
nothing else needs to be added.
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.
Notice: If an improper coolant
mixture is used, the engine could
overheat and be badly damaged.
The repair cost would not be
covered by the vehicle warranty.
Too much water in the mixture
can freeze and crack the engine,
radiator, heater core, and other
parts. Notice:
If extra inhibitors and/or
additives are used in the vehicle
cooling system, the vehicle
could be damaged. Use only the
proper mixture of the engine
coolant listed in this manual for
the cooling system. See
Recommended Fluids and
Lubricants on page 11‑11 for
more information.
Never dispose of engine coolant
by putting it in the trash, 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.

Black plate (23,1)GMC Yukon/Yukon XL Owner Manual - 2012
Vehicle Care 10-23
.Idles for long periods in traffic.
.Tows a trailer. SeeTrailer
Towing on page 9‑72.
If the overheat warning is displayed
with no sign of steam:
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. In heavy traffic, let the engine idle in N (Neutral) while stopped.
If 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. If the warning continues, pull
over, stop, and park the vehicle
right away.
If there is no sign of steam, idle
the engine for three minutes
while parked. If the warning is still
displayed, turn off the engine until it
cools down. Also, see
“Overheated
Engine Protection Operating Mode”
later in this section.
Overheated Engine
Protection
Operating Mode
If an overheated engine condition
exists and the ENGINE POWER IS
REDUCED message is displayed,
an overheat protection mode which
alternates firing groups of cylinders
helps prevent engine damage. In
this mode, a loss in power and
engine performance will be noticed.
This operating mode allows the
vehicle to be driven to a safe place
in an emergency. Driving extended distances and/or towing a trailer in
the overheat protection mode
should be avoided.
Notice:
After driving in the
overheated engine protection
operating mode, to avoid engine
damage, allow the engine to cool
before attempting any repair.
The engine oil will be severely
degraded. Repair the cause of
coolant loss, change the oil and
reset the oil life system. See
Engine Oil on page 10‑8.
Engine Fan
If the vehicle has a clutched engine
cooling fan, when the clutch is
engaged, the fan spins faster to
provide more air to cool the engine.
In most everyday driving conditions,
the fan is spinning slower and the
clutch is not fully engaged.
This improves fuel economy and
reduces fan noise. Under heavy
vehicle loading, trailer towing, and/
or high outside temperatures, the
fan speed increases as the clutch

Black plate (4,1)GMC Yukon/Yukon XL Owner Manual - 2012
i-4 INDEX
DoorAjar Messages . . . . . . . . . . . . . . . 5-39
Delayed Locking . . . . . . . . . . . . . . . 2-8
Locks . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
Power Locks . . . . . . . . . . . . . . . . . . . 2-8
Drive Belt Routing, Engine . . . . . 12-4
Driver Information Center (DIC) . . . . . . . . . . . . . . . . . 5-29
Driving Characteristics andTowing Tips . . . . . . . . . . . . . . . . . 9-68
Defensive . . . . . . . . . . . . . . . . . . . . . . 9-3
Drunk . . . . . . . . . . . . . . . . . . . . . . . . . . 9-3
For Better Fuel Economy . . . . . 1-27
Highway Hypnosis . . . . . . . . . . . . 9-12
Hill and Mountain Roads . . . . . . 9-13
If the Vehicle is Stuck . . . . . . . . . 9-15
Loss of Control . . . . . . . . . . . . . . . . 9-5
Off-Road . . . . . . . . . . . . . . . . . . . . . . 9-6
Off-Road Recovery . . . . . . . . . . . . 9-5
Vehicle Load Limits . . . . . . . . . . . 9-16
Wet Roads . . . . . . . . . . . . . . . . . . . 9-11
Winter . . . . . . . . . . . . . . . . . . . . . . . . 9-13
Dual Automatic Climate Control System . . . . . . . . . . . . . . . . 8-4 DVD
Rear Seat Entertainment
System . . . . . . . . . . . . . . . . . . . . . . 7-34
DVD/CD Player . . . . . . . . . . . . . . . . 7-19
E
E85 Fuel . . . . . . . . . . . . . . . . . . . . . . . 9-64
Electrical Equipment, Add-On . . . . . . . . . . . . . . . . . . . . . . 9-86
Electrical System Engine CompartmentFuse Block . . . . . . . . . . . . . . . . 10-41
Fuses and Circuit
Breakers . . . . . . . . . . . . . . . . . . 10-40
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . . 10-45
Overload . . . . . . . . . . . . . . . . . . . 10-39
Emergency, OnStar
®. . . . . . . . . . 14-2
Engine Air Cleaner/Filter . . . . . . . . . . . 10-15
Check and Service EngineSoon Light . . . . . . . . . . . . . . . . . . 5-21
Compartment Overview . . . . . . . 10-6
Coolant . . . . . . . . . . . . . . . . . . . . . 10-17
Coolant Temperature
Gauge . . . . . . . . . . . . . . . . . . . . . . 5-16 Engine (cont'd)
Cooling System . . . . . . . . . . . . . 10-16
Cooling System Messages . . . 5-39
Drive Belt Routing . . . . . . . . . . . . 12-4
Exhaust . . . . . . . . . . . . . . . . . . . . . . 9-30
Fan . . . . . . . . . . . . . . . . . . . . . . . . . 10-23
Heater . . . . . . . . . . . . . . . . . . . . . . . . 9-26
Oil Pressure Gauge . . . . . . . . . . 5-15
Overheated Protection
Operating Mode . . . . . . . . . . . 10-23
Overheating . . . . . . . . . . . . . . . . 10-21
Power Messages . . . . . . . . . . . . . 5-41
Pressure Light . . . . . . . . . . . . . . . . 5-27
Running While Parked . . . . . . . . 9-30
Starting . . . . . . . . . . . . . . . . . . . . . . . 9-24
Engine Oil Life System . . . . . . . . . . . . . . . . . 10-10
Messages . . . . . . . . . . . . . . . . . . . . 5-40
Entry Lighting . . . . . . . . . . . . . . . . . . . 6-9
Equipment, Towing . . . . . . . . . . . . 9-76
Event Data Recorders . . . . . . . . 13-14
Exit Lighting . . . . . . . . . . . . . . . . . . . . 6-9
Extender, Safety Belt . . . . . . . . . . 3-28
Exterior Lamp Controls . . . . . . . . . 6-1
Exterior Lamps Off Reminder . . . 6-2

Black plate (6,1)GMC Yukon/Yukon XL Owner Manual - 2012
i-6 INDEX
General InformationService and Maintenance . . . . . 11-1
Towing . . . . . . . . . . . . . . . . . . . . . . . . 9-67
Vehicle Care . . . . . . . . . . . . . . . . . . 10-2
Glass Replacement . . . . . . . . . . . 10-34
Glove Box . . . . . . . . . . . . . . . . . . . . . . 4-1
GM Mobility Reimbursement Program . . . . . . . . . . . . . . . . . . . . . . 13-5
H
Halogen Bulbs . . . . . . . . . . . . . . . . 10-37
Hazard Warning Flashers . . . . . . . 6-5
Head Restraints . . . . . . . . . . . . . . . . 3-2
HeadlampsAiming . . . . . . . . . . . . . . . . . . . . . . 10-35
Automatic . . . . . . . . . . . . . . . . . . . . . . 6-4
Bulb Replacement . . . . . . . . . . 10-37
Daytime RunningLamps (DRL) . . . . . . . . . . . . . . . . . 6-3
Flash-to-Pass . . . . . . . . . . . . . . . . . . 6-3
High-Beam On Light . . . . . . . . . . 5-28
High/Low Beam Changer . . . . . . 6-3
Heated
Rear Seats . . . . . . . . . . . . . . . . . . . 3-10 Heated and Ventilated Front
Seats . . . . . . . . . . . . . . . . . . . . . . . . . 3-9
Heated Mirrors . . . . . . . . . . . . . . . . . 2-19
Heater Engine . . . . . . . . . . . . . . . . . . . . . . . . 9-26
Heating and Air Conditioning . . . 8-1
High-Beam On Light . . . . . . . . . . . 5-28
Highway Hypnosis . . . . . . . . . . . . . 9-12
Hill and Mountain Roads . . . . . . . 9-13
Hill Start Assist (HSA) . . . . . . . . . 9-46
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . 10-5
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
How to Wear Safety Belts Properly . . . . . . . . . . . . . . . . . . . . . . 3-21
I
Ignition Positions . . . . . . . . . . . . . . 9-22
Ignition Transmission LockCheck . . . . . . . . . . . . . . . . . . . . . . . 10-33
Immobilizer . . . . . . . . . . . . . . . . . . . . 2-15
Infants and Young Children, Restraints . . . . . . . . . . . . . . . . . . . . 3-47
Infotainment . . . . . . . . . . . . . . . . . . . . 7-1 Instrument Cluster . . . . . . . . . . . . . 5-12
Instrument Panel Overview . . . . . 1-2
Introduction . . . . . . . . . . . . . . . . . . . . . . . iii
J
Jump Starting . . . . . . . . . . . . . . . . . 10-88
K
Key and Lock Messages . . . . . . . 5-41
Keyless Entry
Remote (RKE) System . . . . . . . . 2-3
Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
L
Labeling, Tire Sidewall . . . . . . . . 10-50
Lamp Messages . . . . . . . . . . . . . . . 5-42
Lamps Auxiliary Roof
Mounted Lamp . . . . . . . . . . . . . . . 6-7
Daytime Running (DRL) . . . . . . . 6-3
Dome . . . . . . . . . . . . . . . . . . . . . . . . . . 6-8
Exterior Controls . . . . . . . . . . . . . . . 6-1
Exterior Lamps Off Reminder . . . . . . . . . . . . . . . . . . . . 6-2