2012 GMC SIERRA 1500 heater

Black plate (20,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
10-20 Vehicle Care
.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 11‑12 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.
Checking Coolant
The coolant surge tank is located in
the engine compartment on the
passenger side of the vehicle. See
Engine Compartment Overview on
page 10‑6
for more information on
location.
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
boiling, do not do anything else until it cools down. If coolant is visible
but the coolant level is not at or
above the FULL COLD mark, add a
50/50 mixture of clean, drinkable
water and DEX-COOL coolant at the
coolant surge tank, but be sure the
cooling system is cool before this
is done.
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.

Black plate (24,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
10-24 Vehicle Care
.Idles for long periods in traffic
.Tows a trailer; seeTrailer Towing
on page 9‑78.
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. If stopped in a traffic jam, apply the brake, shift to N (Neutral);
otherwise, shift to the highest
gear while driving —D (Drive)
or 3 (Third).
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 five 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 displays, an
overheat protection mode which
alternates firing groups of cylinders
helps to 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 km (mi) 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 10‑7.
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

Black plate (4,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
i-4 INDEX
D
Damage Repair, Collision . . . . . 13-14
Danger, Warnings, andCautions . . . . . . . . . . . . . . . . . . . . . . . . iv
Data Recorders, Event . . . . . . . 13-19
Daytime Running Lamps (DRL) . . . . . . . . . . . . . . . . . . 6-3
Defensive Driving . . . . . . . . . . . . . . . 9-3
Delayed Locking . . . . . . . . . . . . . . . . 2-8
Devices, Auxiliary . . . . . . . . . . . . . 7-32
Diagnostics, OnStar
®. . . . . . . . . . 14-5
Distracted Driving . . . . . . . . . . . . . . . 9-2
Dome Lamps . . . . . . . . . . . . . . . . . . . 6-8
Door Ajar Messages . . . . . . . . . . . . . . . 5-40
Delayed Locking . . . . . . . . . . . . . . . 2-8
Locks . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
Power Locks . . . . . . . . . . . . . . . . . . . 2-8
Rear Doors . . . . . . . . . . . . . . . . . . . . 2-9
Drive Belt Routing, Engine . . . . . 12-6
Driver Information
Center (DIC) . . . . . . . . . . . . . . . . . 5-30 Driving
Characteristics and
Towing Tips . . . . . . . . . . . . . . . . . 9-74
Defensive . . . . . . . . . . . . . . . . . . . . . . 9-3
Drunk . . . . . . . . . . . . . . . . . . . . . . . . . . 9-3
For Better Fuel Economy . . . . . 1-36
Highway Hypnosis . . . . . . . . . . . . 9-12
Hill and Mountain Roads . . . . . . 9-12
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 . . . . . . . . . . . . . . . . 8-5
Dual Tire Rotation . . . . . . . . . . . . . . . . . . . . 10-67
DVD Rear Seat Entertainment
System . . . . . . . . . . . . . . . . . . . . . . 7-37
DVD/CD Player . . . . . . . . . . . . . . . . 7-21
E
E85 Fuel . . . . . . . . . . . . . . . . . . . . . . . 9-71
Electrical Equipment, Add-On . . . . . . . . . . . . . . . . . . . . . 9-105
Electrical System Engine CompartmentFuse Block . . . . . . . . . . . . . . . . 10-44
Fuses and Circuit Breakers . . . . . . . . . . . . . . . . . . 10-44
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . . 10-48
Overload . . . . . . . . . . . . . . . . . . . 10-43
Emergency, OnStar
®. . . . . . . . . . 14-2
Engine Air Cleaner/Filter . . . . . . . . . . . 10-17
Check and Service EngineSoon Light . . . . . . . . . . . . . . . . . . 5-22
Compartment Overview . . . . . . . 10-6
Coolant . . . . . . . . . . . . . . . . . . . . . 10-19
Coolant Heater . . . . . . . . . . . . . . . 9-30
Coolant Temperature Gauge . . . . . . . . . . . . . . . . . . . . . . 5-16
Cooling System . . . . . . . . . . . . . 10-18

Black plate (6,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
i-6 INDEX
Fuel (cont'd)Management, Active . . . . . . . . . . 9-32
Recommended . . . . . . . . . . . . . . . 9-68
Requirements, California . . . . . 9-69
System Messages . . . . . . . . . . . . 5-43
Full-Size Spare Tire . . . . . . . . . . 10-87
Fuses Engine CompartmentFuse Block . . . . . . . . . . . . . . . . 10-44
Fuses and Circuit Breakers . . . . . . . . . . . . . . . . . . 10-44
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . . 10-48
G
Garage Door Opener . . . . . . . . . . 5-56Programming . . . . . . . . . . . . . . . . . 5-56
Gasoline Specifications . . . . . . . . . . . . . . . . . 9-69 Gauges
Engine Coolant
Temperature . . . . . . . . . . . . . . . . 5-16
Engine Oil Pressure . . . . . . . . . . 5-15
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . 5-14
Odometer . . . . . . . . . . . . . . . . . . . . . 5-13
Speedometer . . . . . . . . . . . . . . . . . 5-13
Tachometer . . . . . . . . . . . . . . . . . . . 5-13
Trip Odometer . . . . . . . . . . . . . . . . 5-13
Voltmeter . . . . . . . . . . . . . . . . . . . . . 5-16
Warning Lights and Indicators . . . . . . . . . . . . . . . . . . . 5-11
General Information Service and Maintenance . . . . . 11-1
Towing . . . . . . . . . . . . . . . . . . . . . . . . 9-74
Vehicle Care . . . . . . . . . . . . . . . . . . 10-2
Glass Replacement . . . . . . . . . . . 10-37
Glove Box . . . . . . . . . . . . . . . . . . . . . . 4-1
GM Mobility Reimbursement Program . . . . . . . . . . . . . . . . . . . . . . 13-7
H
Halogen Bulbs . . . . . . . . . . . . . . . . 10-39
Hazard Warning Flashers . . . . . . . 6-5
Head Restraints . . . . . . . . . . . . . . . . 3-2
HeadlampsAiming . . . . . . . . . . . . . . . . . . . . . . 10-37
Automatic . . . . . . . . . . . . . . . . . . . . . . 6-4
Bulb Replacement . . . . . . . . . . 10-39
Daytime RunningLamps (DRL) . . . . . . . . . . . . . . . . . 6-3
Flash-to-Pass . . . . . . . . . . . . . . . . . . 6-3
Headlamps, Front Turn
Signal, Sidemarker, and
Parking Lamps . . . . . . . . . . . . 10-39
High-Beam On Light . . . . . . . . . . 5-29
High/Low Beam Changer . . . . . . 6-3
Heated and Ventilated Front Seats . . . . . . . . . . . . . . . . . . . . . . . . . 3-9
Heated Mirrors . . . . . . . . . . . . . . . . . 2-17
Heater Engine Coolant . . . . . . . . . . . . . . . 9-30