2007 HUMMER H3 overheating

Ashtray(s) and Cigarette Lighter
Your vehicle may have an ashtray and cigarette
lighter.
Your ashtray is located in your center console
area. The ashtray can be removed for cleaning.
When the ashtray is removed, this area can
also be used as a cupholder.
Notice:If you put papers, pins, or other
ammable items in the ashtray, hot cigarettes
or other smoking materials could ignite
them and possibly damage your vehicle.
Never put ammable items in the ashtray.
To use the lighter, press it in all the way, and let
go. When it’s ready, it will pop back out by itself.
Notice:Holding a cigarette lighter in while it
is heating will not allow the lighter to back
away from the heating element when it is hot.
Damage from overheating may occur to the
lighter or heating element, or a fuse could
be blown. Do not hold a cigarette lighter
in while it is heating.
Climate Controls
Climate Control System
This system controls the heating, cooling, and
ventilation of the vehicle. In-between modes are
available by moving the right control knob between
modes with symbols. The in-between mode will
be a combination of the two modes that the control
is centered between.
Temperature:Turn the left knob on the control
panel to adjust the temperature of the air in
the vehicle. Turn the knob clockwise or
counterclockwise to increase or decrease the
temperature.
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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 338for more
information.
Tire Pressure Light
This light should
come on briey
when you turn the
ignition to ON.
This light will also come on when one or more
of your tires are signicantly underinated.
A LOW TIRE message will also appear in the
Driver Information Center (DIC), seeDIC Warnings
and Messages on page 196for more information.
Stop and check your tires as soon as it is safe to do
so. If underinated, inate to the proper pressure.
SeeTires on page 367for more information.
This light will ash for 60 seconds and then turn
on solid if a problem is detected with the Tire
Pressure Monitor system. SeeTire Pressure
Monitor System on page 376for more information.
United StatesCanada
185

DIC Warnings and Messages
Messages are displayed on the DIC to notify the
driver that the status of the vehicle has changed
and that some action may be needed by the driver
to correct the condition. Multiple messages may
appear one after another. The messages are
displayed for four seconds each.
Some messages may not require immediate
action, but you should press and release the trip
odometer reset stem to acknowledge that you
received the messages and to clear them from the
display. Each message must be acknowledged
individually.
Some messages cannot be cleared from the DIC
display because they are more urgent. These
messages require action before they can be
cleared. You should take any messages that
appear on the display seriously and remember
that clearing the messages will only make
the messages disappear, not correct the problem.
The following are the possible messages that can
be displayed and some information about them.
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 338andClimate Control
System on page 170for more information.
This message displays along with the ENG HOT
message.
ABS (Anti-Lock Brake System) FAULT
This message displays if there is a problem
with the Anti-Lock Brake System (ABS). Check the
ABS as soon as possible and have your vehicle
serviced by your dealer. SeeBrakes on page 347
andAnti-Lock Brake System Warning Light on
page 183for more information. Press and release
the reset stem to acknowledge the message
and clear it from the display.
196

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.
SeeBrakes on page 347andBrake System
Warning Light on page 182for 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. SeeEngine Oil on page 323
andScheduled Maintenance on page 429for
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 185. Have your
vehicle serviced by your dealer as soon as
possible if you suspect the engine is overheating.
SeeEngine Overheating on page 338for more
information.
FLUID
This message displays if the brake uid is low.
Check the brake uid as soon as possible
and have your vehicle serviced by your dealer.
SeeBrakes on page 347for more information.
Press and release the reset stem to acknowledge
the message and clear it from the display.
197

Turn Signals When Towing a Trailer
The arrows on your instrument panel will ash
whenever you signal a turn or lane change.
Properly hooked up, the trailer lamps will also ash,
telling other drivers you’re about to turn, change
lanes or stop.
When towing a trailer, the arrows on your
instrument panel will ash for turns even if the bulbs
on the trailer are burned out. Thus, you may think
drivers behind you are seeing your signal when
they are not. It’s important to check occasionally to
be sure the trailer bulbs are still working.
Driving On Grades
Reduce speed and shift to a lower gearbefore
you 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 338.
305

Service........................................................ 314
Accessories and Modications................... 314
California Proposition 65 Warning.............. 315
Doing Your Own Service Work.................. 315
Adding Equipment to the Outside
of Your Vehicle...................................... 316
Fuel............................................................. 316
Gasoline Octane........................................ 316
Gasoline Specications.............................. 316
California Fuel........................................... 316
Additives................................................... 317
Fuels in Foreign Countries........................ 318
Filling the Tank......................................... 318
Filling a Portable Fuel Container............... 320
Checking Things Under the Hood.............. 321
Hood Release........................................... 321
Engine Compartment Overview.................. 322
Engine Oil................................................. 323Engine Oil Life System.............................. 326
Engine Air Cleaner/Filter............................ 328
Automatic Transmission Fluid.................... 329
Manual Transmission Fluid........................ 332
Hydraulic Clutch........................................ 334
Engine Coolant.......................................... 335
Radiator Pressure Cap.............................. 338
Engine Overheating................................... 338
Cooling System......................................... 340
Engine Fan Noise..................................... 345
Power Steering Fluid ................................. 345
Windshield Washer Fluid........................... 346
Brakes...................................................... 347
Battery...................................................... 351
Jump Starting............................................ 352
Rear Axle.................................................... 357
Four-Wheel Drive........................................ 358
Front Axle................................................... 358
Section 5 Service and Appearance Care
311

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 338.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.
335

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 340.
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 322
for more information on location.
Engine Overheating
A coolant temperature gage is on the instrument
panel. SeeEngine Coolant Temperature Gage
on page 185.
The air conditioning might stop working if the
engine is too hot. This is normal and helps cool
the engine.
If Steam Is Coming From Your Engine
{CAUTION:
Steam from an overheated engine can
burn you badly, even if you just open the
hood. Stay away from the engine if you
see or hear steam coming from it. Just
turn it off and get everyone away from the
vehicle until it cools down.Wait until there
is no sign of steam or coolant before you
open the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch re.
CAUTION: (Continued)
338