coolant temperature HUMMER H3 2008 Owners Manual

Engine Coolant Heater
The engine coolant heater, if available, can help in cold
weather conditions at or below 0°F (−18°C) for easier
starting and better fuel economy during engine warm-up.
Plug in the coolant heater at least four hours before
starting your vehicle. An internal thermostat in the
plug-end of the cord may exist which will prevent
engine coolant heater operation at temperatures
above 0° F (−18°C).
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord.
The cord is located in the engine compartment
behind the underhood fuse block on the driver’s
side of the vehicle.
3. Plug it into a normal, grounded 110-volt AC outlet.
{CAUTION:
Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the
wrong kind of extension cord could overheat
and cause a re. You could be seriously
injured. Plug the cord into a properly grounded
three-prong 110-volt AC outlet. If the cord will
not reach, use a heavy-duty three-prong
extension cord rated for at least 15 amps.
4. Before starting the engine, be sure to unplug and
store the cord as it was before to keep it away
from moving engine parts. If you do not, it could be
damaged.
How long should you keep the coolant heater plugged
in? The answer depends on the outside temperature, the
kind of oil you have, and some other things. Instead
of trying to list everything here, we ask that you contact
your dealer/retailer in the area where you will be
parking your vehicle. The dealer/retailer can give you
the best advice for that particular area.
2-22

Instrument Panel Overview...............................3-4
Hazard Warning Flashers................................3-6
Other Warning Devices...................................3-6
Horn.............................................................3-6
Tilt Wheel.....................................................3-7
Turn Signal/Multifunction Lever.........................3-7
Turn and Lane-Change Signals........................3-8
Headlamp High/Low-Beam Changer..................3-9
Flash-to-Pass.................................................3-9
Windshield Wipers........................................3-10
Windshield Washer.......................................3-10
Rear Window Wiper/Washer...........................3-11
Cruise Control..............................................3-11
Exterior Lamps.............................................3-15
Headlamps on Reminder................................3-16
Daytime Running Lamps (DRL).......................3-17
Automatic Headlamp System..........................3-17
Off-Road Lamps...........................................3-18
Fog Lamps..................................................3-19
Instrument Panel Brightness...........................3-19
Dome Lamp.................................................3-19
Dome Lamp Override....................................3-20
Exit Lighting.................................................3-20
Reading Lamps............................................3-20Electric Power Management...........................3-20
Battery Run-Down Protection..........................3-20
Accessory Power Outlet(s).............................3-21
Ashtray(s) and Cigarette Lighter......................3-22
Climate Controls............................................3-22
Climate Control System.................................3-22
Outlet Adjustment.........................................3-24
Warning Lights, Gages, and Indicators............3-25
Instrument Panel Cluster................................3-26
Speedometer and Odometer..........................
.3-27
Trip Odometer..............................................3-27
Tachometer.................................................3-27
Safety Belt Reminders...................................3-28
Airbag Readiness Light..................................3-29
Passenger Airbag Status Indicator...................3-30
Charging System Light..................................3-32
Up-Shift Light...............................................3-32
Brake System Warning Light..........................3-33
Antilock Brake System Warning Light...............3-34
Traction Off Light..........................................3-34
StabiliTrak
®Not Ready Light..........................3-34
Engine Coolant Temperature Gage..................3-35
Tire Pressure Light.......................................3-35
Section 3 Instrument Panel
3-1

Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
If the gage pointer is in the shaded area of the gage,
the engine is too hot. It means that your engine coolant
has overheated. If you have been operating your
vehicle under normal driving conditions, you should pull
off the road, stop your vehicle and turn off the engine
as soon as possible.
SeeEngine Overheating on page 5-29for more
information.
Tire Pressure Light
This light comes on briey
when the engine is started.
This light will also come on when one or more of your
tires are signicantly underinated.
A tire pressure message in the Driver Information
Center (DIC), may accompany the light. SeeDIC
Warnings and Messages on page 3-43for more
information.
Stop and check your tires as soon as it is safe to do so.
If underinated, inate to the proper pressure. See
Tires on page 5-54for more information.
If a problem is detected with the Tire Pressure Monitor
System, this light will ash for approximately
60 seconds and then stay on solid for the remainder of
the ignition cycle. SeeTire Pressure Monitor System
on page 5-63for more information. United States
Canada
3-35

AC (Air Conditioning) OFF
This message displays when the engine coolant
temperature is too high and the air conditioning in your
vehicle needs to be turned off. SeeEngine Overheating
on page 5-29andClimate Control System on
page 3-22for more information. This message displays
along with the ENG HOT message.
ABS (Antilock Brake System) FAULT
This message displays if there is a problem with
the Antilock Brake System (ABS). Check the ABS as
soon as possible and have your vehicle serviced by your
dealer/retailer. SeeBrakes on page 5-38andAntilock
Brake System Warning Light on page 3-34for more
information. Press and release the reset stem to
acknowledge the message and clear it from the display.
BRAKES
This message displays if there is a problem with the
brakes. Check the brakes as soon as possible and have
your vehicle serviced by your dealer/retailer. See
Brakes on page 5-38andBrake System Warning Light
on page 3-33for more information. Press and release
the reset stem to acknowledge the message and clear it
from the display.
CHANGE OIL
This message displays when the oil needs to be
changed. Check the oil in your vehicle as soon as
possible and have your vehicle serviced by your
dealer/retailer. SeeEngine Oil on page 5-15and
Scheduled Maintenance on page 6-4for more
information. Press and release the reset stem to
acknowledge the message and clear it from the display.
DOORS
This message displays when one or more of the doors
is ajar. Check all the doors on your vehicle to make
sure they are closed. The message clears from
the display after all of the doors are closed.
ENG (Engine) HOT
This message displays when the engine coolant
temperature is hot. Check the engine coolant
temperature gage. SeeEngine Coolant Temperature
Gage on page 3-35. Have your vehicle serviced by your
dealer/retailer as soon as possible if you suspect the
engine is overheating. SeeEngine Overheating on
page 5-29for more information.
3-44

Driving On Grades
Reduce speed and shift to a lower gearbeforeyou start
down a long or steep downgrade. If you don’t shift
down, you might have to use your brakes so much
that they would get hot and no longer work well.
If you have an automatic transmission, you can tow
in DRIVE (D). You may want to shift the transmission to
THIRD (3) or, if necessary, a lower gear selection if
the transmission shifts too often under heavy loads
and/or hilly conditions.
If you have a manual transmission and you are towing a
trailer, it is better not to use the highest gear.
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a lower
temperature than at normal altitudes. If you turn your
engine off immediately after towing at high altitude on
steep uphill grades, your vehicle may show signs similar
to engine overheating. To avoid this, let the engine run
while parked, preferably on level ground, with the
automatic transmission in PARK (P) for a few minutes
before turning the engine off. For manual transmissions,
let the engine run while parked, preferably on level
ground, with the transmission out of gear and the parking
brake applied, for a few minutes before turning the engine
off. If you do get the overheat warning, seeEngine
Overheating on page 5-29.
Parking on Hills
{CAUTION:
You really should not park your vehicle, with a
trailer attached, on a hill. If something goes
wrong, your rig could start to move. People
can be injured, and both your vehicle and the
trailer can be damaged.
But if you ever have to park your rig on a hill, here’s
how to do it:
1. Apply your regular brakes, but don’t shift into
PARK (P) yet for an automatic transmission, or into
gear for a manual transmission. Turn your wheels
into the curb if facing downhill or into traffic if facing
uphill.
2. Have someone place chocks under the trailer
wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4. Reapply the regular brakes. Then apply your
parking brake and shift into PARK (P) for an
automatic transmission or into gear for a manual
transmission.
5. Release the regular brakes.
4-58

How to Check and Add Fluid
The proper uid should be added if the level does not
reach the bottom of the diaphragm when it is in place in
the reservoir. See the instructions on the reservoir cap.
Engine Coolant
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 5-29.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.
5-27

Adding Coolant
If you need more coolant, add the proper DEX-COOL®
coolant mixture at the coolant recovery tank.
{CAUTION:
Turning the radiator pressure cap when the
engine and radiator are hot can allow steam and
scalding liquids to blow out and burn you badly.
With the coolant recovery tank, you will almost
never have to add coolant at the radiator. Never
turn the radiator pressure cap — even a little —
when the engine and radiator are hot.
Add coolant mixture at the recovery tank, but be careful
not to spill it.
{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.Occasionally check the coolant level in the radiator.
For information on how to add coolant to the radiator,
seeCooling System on page 5-31.
Radiator Pressure Cap
Notice: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.
SeeEngine Compartment Overview on page 5-12for
more information on location.
Engine Overheating
A coolant temperature gage is on the instrument panel.
SeeEngine Coolant Temperature Gage on page 3-35.
The air conditioning might stop working if the engine
is too hot. This is normal and helps cool the engine.
5-29

4. Replace the cap and completely tighten it.
5. Then remove the cap again and look at the uid
level on the dipstick.
The level should be between the ADD and FULL marks.
If necessary, add only enough uid to bring the level
up to the proper range.
What to Use
To determine what kind of uid to use, see
Recommended Fluids and Lubricants on page 6-12.
Always use the proper uid.
Notice:Use of the incorrect uid may damage your
vehicle and the damages may not be covered by
your warranty. Always use the correct uid listed in
Recommended Fluids and Lubricants on page 6-12.
Windshield Washer Fluid
What to Use
When you need windshield washer uid, be sure to read
the manufacturer’s instructions before use. If you will be
operating your vehicle in an area where the temperature
may fall below freezing, use a uid that has sufficient
protection against freezing.
Adding Washer Fluid
Open the cap with the
washer symbol on it. Add
washer uid until the
tank is full. SeeEngine
Compartment Overview on
page 5-12for reservoir
location.
Notice:
When using concentrated washer uid, follow the
manufacturer’s instructions for adding water.
Do not mix water with ready-to-use washer uid.
Water can cause the solution to freeze and
damage your washer uid tank and other parts of
the washer system. Also, water does not clean as
well as washer uid.
Fill the washer uid tank only three-quarters full
when it is very cold. This allows for uid
expansion if freezing occurs, which could
damage the tank if it is completely full.
Do not use engine coolant (antifreeze) in your
windshield washer. It can damage the vehicle’s
windshield washer system and paint.
5-37

(d)Inspect wiper blades for wear, cracking, or
contamination. Clean the windshield and wiper blades, if
contaminated. Replace wiper blades that are worn or
damaged. See Windshield Wiper Blade Replacement on
page 5-52 and Windshield, Backglass, and Wiper
Blades on page 5-97 for more information.
(e)Make sure the safety belt reminder light and safety
belt assemblies are working properly. Look for any
other loose or damaged safety belt system parts. If you
see anything that might keep a safety belt system
from doing its job, have it repaired. Have any torn or
frayed safety belts replaced. Also see Checking
the Restraint Systems on page 1-69.
(f)Lubricate all key lock cylinders, hood latch assembly,
secondary latch, pivots, spring anchor, release pawl,
rear compartment hinges, outer swing-gate handle pivot
points, rear door detent link, roller mechanism,
swing-gate handle pivot points, latch bolt, fuel door
hinge, locks, and folding seat hardware. More frequent
lubrication may be required when exposed to a
corrosive environment. Applying silicone grease on
weatherstrips with a clean cloth will make them
last longer, seal better, and not stick or squeak.(g)Check vent hose at transfer case for kinks and
proper installation.
(h)Change automatic transmission fluid and filter if the
vehicle is mainly driven under one or more of these
conditions:
In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police, or delivery
service.
(i)Drain, flush, and refill cooling system. This service
can be complex; you should have your dealer/retailer
perform this service. See Engine Coolant on page 5-27
for what to use. Inspect hoses. Clean radiator,
condenser, pressure cap, and filler neck. Pressure test
the cooling system and pressure cap.
(j)A fluid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired and
the fluid level checked. Add fluid if needed.
(k)Visually inspect belt for fraying, excessive cracks, or
obvious damage. Replace belt if necessary.
6-8

Child Restraints
Child Restraint Systems...............................1-37
Infants and Young Children...........................1-33
Lower Anchors and Tethers for Children..........1-42
Older Children.............................................1-30
Securing a Child Restraint in a
Rear Outside Seat Position........................1-48
Securing a Child Restraint in the
Center Rear Seat Position.........................1-50
Securing a Child Restraint in the
Right Front Seat Position..........................1-51
Where to Put the Restraint...........................1-40
Cigarette Lighter.............................................3-22
Cleaning
Aluminum or Chrome-Plated Wheels..............5-97
Exterior Lamps/Lenses.................................5-95
Fabric/Carpet..............................................5-93
Finish Care.................................................5-96
Instrument Panel, Vinyl, and Other
Plastic Surfaces.......................................5-94
Interior.......................................................5-91
Leather......................................................5-93
Tires..........................................................5-98
Underbody Maintenance...............................5-98
Washing Your Vehicle...................................5-95
Weatherstrips..............................................5-94
Windshield, Backglass, and Wiper Blades.......5-97
Climate Control System...................................3-22
Outlet Adjustment........................................3-24Clock............................................................3-48
Clutch, Hydraulic.............................................5-26
Collision Damage Repair..................................7-11
Compass...............................................2-38, 2-41
Content Theft-Deterrent....................................2-14
Control of a Vehicle.......................................... 4-3
Convenience Net............................................2-59
Coolant
Engine Temperature Gage............................3-35
Heater, Engine............................................
2-22
Cooling System..............................................5-31
Cruise Control................................................3-11
Cruise Control Light........................................3-39
Cupholder(s)..................................................2-56
Customer Assistance Information
Courtesy Transportation.................................. 7-9
Customer Assistance for
Text Telephone (TTY) Users........................ 7-5
Customer Assistance Offices........................... 7-5
Customer Satisfaction Procedure..................... 7-2
GM Mobility Reimbursement Program............... 7-6
Reporting Safety Defects to General Motors.....7-15
Reporting Safety Defects to the
Canadian Government..............................7-15
Reporting Safety Defects to the
United States Government.........................7-14
Roadside Assistance Program......................... 7-6
Service Publications Ordering Information........7-15
3