heater GMC SIERRA 2008 User Guide

Rear Window Defogger
If your vehicle has a rear window defogger it uses a
warming grid to remove fog from the rear window.
The rear window defogger will only work when
the ignition is in RUN.
<(Rear):Press this button to turn the rear window
defogger on or off. An indicator light on the button
will come on to let you know that the rear window
defogger is activated.
The rear window defogger will only work when the
ignition is in RUN. The rear window defogger will stay
on for approximately 10 minutes after the button is
pressed, unless the ignition is turned to ACC or LOCK.
The defogger can also be turned off by pressing the
button again or by turning off the engine.
Notice:Do not use anything sharp on the inside of
the rear window. If you do, you could cut or
damage the warming grid, and the repairs would not
be covered by your warranty. Do not attach a
temporary vehicle license, tape, a decal or anything
similar to the defogger grid.
Climate Control System
(Heater Only)
With this system you can control the heating and
ventilation for your vehicle.
Operation
9
(Fan):Turn the left knob clockwise or
counterclockwise to increase or decrease the fan speed.
Turn the knob all the way counterclockwise to turn the
front system off.
Temperature Control:Turn the center knob clockwise
or counterclockwise to increase or decrease the
temperature inside the vehicle.
3-27

Your vehicle has one of these radios as its audio
system.
Radios with CD and DVD
Radios with CD and DVD have a Bose®Surround
Sound System. Some of its features are explained later
in this section under, “Adjusting the Speakers
(Balance/Fade)”.
If your vehicle has a Rear Seat Entertainment (RSE)
system, it has a CD/DVD radio. SeeRear Seat
Entertainment (RSE) System on page 3-113for more
information on the vehicle’s RSE system.
The DVD player is the top slot on the radio faceplate.
The player is capable of reading the DTS programmed
DVD Audio or DVD Video media, (DTS and DTS
Digital Surround are registered trademarks of Digital
Theater Systems, Inc.).
Manufactured under license from Dolby
®Laboratories.
Dolby®and the double-D symbol are trademarks of
Dolby®Laboratories. Radio with CD and DVD (MP3)
3-85

You can run the engine to keep warm, but be careful.
{CAUTION:
Snow can trap exhaust gases under your
vehicle. This can cause deadly CO (carbon
monoxide) gas to get inside. CO could
overcome you and kill you. You cannot see it
or smell it, so you might not know it is in your
vehicle. Clear away snow from around the
base of your vehicle, especially any that is
blocking the exhaust pipe. And check around
again from time to time to be sure snow does
not collect there.
Open a window just a little on the side of the
vehicle that is away from the wind. This will
help keep CO out.
Run your engine only as long as you must. This saves
fuel. When you run the engine, make it go a little
faster than just idle. That is, push the accelerator
slightly. This uses less fuel for the heat that you get and
it keeps the battery charged. You will need a
well-charged battery to restart the vehicle, and possibly
for signaling later on with the headlamps. Let the
heater run for a while.
4-33

Driving with a Trailer
{CAUTION:
If you have a rear-most window open and you
pull a trailer with your vehicle, carbon
monoxide (CO) could come into your vehicle.
You cannot see or smell CO. It can cause
unconsciousness or death. SeeEngine
Exhaust on page 2-53. To maximize your safety
when towing a trailer:
Have your exhaust system inspected for
leaks, and make necessary repairs before
starting on your trip.
Keep the rear-most windows closed.
CAUTION: (Continued)
CAUTION: (Continued)

If exhaust does come into your vehicle
through a window in the rear or another
opening, drive with your front, main
heating or cooling system on and with the
fan on any speed. This will bring fresh,
outside air into your vehicle. Do not use
the climate control setting for maximum air
because it only recirculates the air inside
your vehicle. SeeClimate Control System
(With Air Conditioning ) on page 3-25or
Climate Control System (Heater Only) on
page 3-27.
Towing a trailer requires a certain amount of experience.
Before setting out for the open road, you’ll want to get
to know your rig. Acquaint yourself with the feel of
handling and braking with the added weight of the trailer.
And always keep in mind that the vehicle you are
driving is now a good deal longer and not nearly as
responsive as your vehicle is by itself.
4-86

To ensure quick starts in the wintertime, the E85 fuel
must be formulated properly for your climate according
to ASTM specication D 5798. If you have trouble
starting on E85, it could be because the E85 fuel is not
properly formulated for your climate. If this happens,
switching to gasoline or adding gasoline to the fuel tank
can improve starting. For good starting and heater
efficiency below 32°F (0°C), the fuel mix in the fuel tank
should contain no more than 70% ethanol. It is best
not to alternate repeatedly between gasoline and E85.
If you do switch fuels, it is recommended that you
add as much fuel as possible — do not add less than
three gallons (11 L) when refueling. You should drive the
vehicle immediately after refueling for at least seven
miles (11 km) to allow the vehicle to adapt to the change
in ethanol concentration.
E85 has less energy per gallon than gasoline, so you
will need to rell the fuel tank more often when using
E85 than when you are using gasoline. SeeFilling the
Tank on page 5-10.Notice:Some additives are not compatible with
E85 fuel and can harm your vehicle’s fuel system.
Do not add anything to E85. Damage caused by
additives would not be covered by your new vehicle
warranty.
Notice:Your vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in the fuel
system and also damage plastic and rubber parts.
That damage would not be covered under your
warranty.
Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel might be hard
to nd. Never use leaded gasoline or any other fuel
not recommended in the previous text on fuel. Costly
repairs caused by use of improper fuel would not be
covered by your warranty.
To check the fuel availability, ask an auto club, or
contact a major oil company that does business in the
country where you will be driving.
5-9

Engine Coolant
If your vehicle has the DURAMAX®Diesel engine, see
the DURAMAX®Diesel manual for more information.
The cooling system in your vehicle is lled with
DEX-COOL
®engine coolant. This coolant is designed
to remain in your vehicle for ve years or 150,000 miles
(240 000 km), whichever occurs rst, if you add only
DEX-COOL
®extended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem
with engine overheating, seeEngine Overheating on
page 5-30.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
Give freezing protection down to−34°F (−37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as they
should.Notice:Using coolant other than DEX-COOL
®may
cause premature engine, heater core, or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at the rst maintenance
service after each 30,000 miles (50 000 km) or
24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
What to Use
Use a mixture of one-half clean, drinkable water and
one-half DEX-COOL®coolant which will not damage
aluminum parts. If you use this coolant mixture, you do
not need to add anything else.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle’s coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
CAUTION: (Continued)
5-28

CAUTION: (Continued)
but you would not get the overheat warning.
Your engine could catch re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.
Notice:If you use an improper coolant mixture,
your engine could overheat and be badly damaged.
The repair cost would not be covered by your
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core, and
other parts.
If you have to add coolant more than four times a year,
have your dealer/retailer check your cooling system.
Notice:If you use extra inhibitors and/or additives
in your vehicle’s cooling system, you could damage
your vehicle. Use only the proper mixture of the
engine coolant listed in this manual for the cooling
system. SeeRecommended Fluids and Lubricants on
page 6-15for more information.
Checking Coolant
The coolant surge tank is located in the engine
compartment on the passenger’s side of the vehicle.
SeeEngine Compartment Overview on page 5-14
for more information on location.
{CAUTION:
Turning the surge tank pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn
you badly. Never turn the surge tank pressure
cap — even a little — when the engine and
radiator are hot.
The vehicle must be on a level surface. When your
engine is cold, the coolant level should be at the FULL
COLD mark on the coolant surge tank.
If your vehicle has a low coolant sensor and the LOW
COOLANT LEVEL message comes on and stays on, it
means you are low on engine coolant. See “LOW
COOLANT LEVEL” underDIC Warnings and Messages
on page 3-63.
5-29

If No Steam Is Coming From Your
Engine
The ENGINE OVERHEATED STOP ENGINE or the
ENGINE OVERHEATED IDLE ENGINE message, along
with a low coolant condition, can indicate a serious
problem.
If you get an engine overheat warning, but see or hear
no steam, the problem may not be too serious.
Sometimes the engine can get a little too hot when you:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer. SeeTowing a Trailer on page 4-55.If you get the ENGINE OVERHEATED STOP ENGINE
or the ENGINE OVERHEATED IDLE ENGINE
message with no sign of steam, try this for a
minute or so:
1. If you have an air conditioner and it is on, turn it off.
2. Turn on your heater to full hot at the highest fan
speed and open the windows as necessary.
3. If you are stopped in a traffic jam, apply the brake,
shift to NEUTRAL (N); otherwise, shift to the
highest gear while driving — DRIVE (D) or
THIRD (3).
5-32

The coolant level should be at or above the FULL
COLD mark. If it is not, you may have a leak at the
pressure cap or in the radiator hoses, heater hoses,
radiator, water pump, or somewhere else in the
cooling system.
{CAUTION:
Heater and radiator hoses, and other engine
parts, can be very hot. Do not touch them.
If you do, you can be burned.
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 re, and you could be
burned. Get any leak xed before you drive the
vehicle.
Notice:Engine damage from running your engine
without coolant is not covered by your warranty.
SeeOverheated Engine Protection Operating Mode
(V8 Engines Only) on page 5-33for information
on driving to a safe place in an emergency.
Notice:Using coolant other than DEX-COOL
®may
cause premature engine, heater core, or radiator
corrosion. In addition, the engine coolant could
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by the warranty. Always use
DEX-COOL
®(silicate-free) coolant in the vehicle.
5-35

Notice:In cold weather, water can freeze and crack
the engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mixture.
{CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol
and it will burn if the engine parts are hot
enough. Do not spill coolant on a hot engine.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 you hear a hiss, wait for that to
stop. A hiss means there is still some pressure left.
2. Then keep turning the pressure cap slowly, and
remove it.
5-37