2007 HUMMER H3 engine overheat

Your vehicle has a Computer-Controlled
Cranking System. This feature assists in
starting the engine and protects components.
If the ignition key is turned to the START
position, and then released when the engine
begins cranking, the engine will continue
cranking for a few seconds or until the vehicle
starts. If the engine does not start and the
key is held in START for many seconds,
cranking stoppes 15 seconds to prevent
cranking motor damage. To prevent gear
damage, this system also prevents cranking if
the engine is already running. Engine
cranking can be stopped by turning the ignition
switch to the ACC or LOCK position.
Notice:Cranking the engine for long periods of
time, by returning the key to the START position
immediately after cranking has ended, can
overheat and damage the cranking motor, and
drain the battery. Wait at least 15 seconds
between each try, to allow the cranking motor
to cool down.2. If the engine does not start after 5-10 seconds,
especially in very cold weather (below 0°F
or−18°C), it could be ooded with too much
gasoline. Try pushing the accelerator
pedal all the way to the oor and holding it
there as you hold the key in START for up to
a maximum of 15 seconds. Wait at least
15 seconds between each try, to allow the
cranking motor to cool down. When the engine
starts, let go of the key and accelerator.
If the vehicle starts briey but then stops
again, do the same thing. This clears the extra
gasoline from the engine. Do not race the
engine immediately after starting it. Operate
the engine and transmission gently until the oil
warms up and lubricates all moving parts.
Notice:Your engine is designed to work with
the electronics in your vehicle. If you add
electrical parts or accessories, you could
change the way the engine operates. Before
adding electrical equipment, check with your
dealer. If you do not, your engine might not
perform properly. Any resulting damage would
not be covered by your vehicle’s warranty.
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Engine Coolant Heater
Your vehicle may have this feature.
In very cold weather, 0°F (–18°C) or colder, the
engine coolant heater can help. You will get easier
starting and better fuel economy during engine
warm-up. Usually, the coolant heater should be
plugged in a minimum of four hours prior to starting
your vehicle. At temperatures above 32°F (0°C),
use of the coolant heater is not required. Your
vehicle may also have an internal thermostat in the
plug end of the cord. This will prevent operation of
the engine coolant heater when the temperature is
at or above 0F (−18C) as noted on the cord.
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 in the area
where you will be parking your vehicle. The dealer
can give you the best advice for that particular area.
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Leaving Your Vehicle With the Engine
Running (Automatic Transmission)
{CAUTION:
It can be dangerous to leave your vehicle
with the engine running. Your vehicle
could move suddenly if the shift lever is
not fully in PARK (P) with the parking
brake rmly set. And, if you leave the
vehicle with the engine running, it could
overheat and even catch re. You or
others could be injured. Do not leave your
vehicle with the engine running.
If you have to leave your vehicle with the engine
running, be sure your vehicle is in PARK (P)
and your parking brake is rmly set before you
leave it. After you have moved the shift lever into
PARK (P), hold the regular brake pedal down.
Then, see if you can move the shift lever
away from PARK (P) without rst pressing the shift
lever button. If you can, it means that the shift
lever was not fully locked into PARK (P).
Torque Lock (Automatic Transmission)
If you are parking on a hill and you do not shift
your transmission into PARK (P) properly,
the weight of the vehicle may put too much force
on the parking pawl in the transmission. You
may nd it difficult to pull the shift lever out
of PARK (P). This is called “torque lock.” To
prevent torque lock, set the parking brake and then
shift into PARK (P) properly before you leave
the driver’s seat. To nd out how, seeShifting Into
Park (P) (Automatic Transmission) on page 117.
When you are ready to drive, move the shift
lever out of PARK (P) before you release the
parking brake.
If torque lock does occur, you may need to have
another vehicle push yours a little uphill to
take some of the pressure from the parking pawl
in the transmission, so you can pull the shift
lever out of PARK (P).
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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
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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.
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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.
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If you decide you can go down a hill safely, then
try to keep your vehicle headed straight down, and
use a low gear. This way, engine drag can help
your brakes and they will not have to do all
the work. Descend slowly, keeping your vehicle
under control at all times.
{CAUTION:
Heavy braking when going down a hill can
cause your brakes to overheat and fade.
This could cause loss of control and a
serious accident. Apply the brakes lightly
when descending a hill and use a low
gear to keep vehicle speed under control.
Q:Are there some things I should not do
when driving down a hill?
A:Yes! These are important because if you
ignore them you could lose control and
have a serious accident:
When driving downhill, avoid turns that take
you across the incline of the hill. A hill that
is not too steep to drive down may be
too steep to drive across. You could roll over
if you do not drive straight down.
Never go downhill with the transmission in
NEUTRAL (N). This is called “free-wheeling.”
Your brakes will have to do all the work
and could overheat and fade.
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If Your Vehicle is Stuck in Sand,
Mud, Ice, or Snow
In order to free your vehicle when it is stuck,
you will need to spin the wheels, but you do not
want to spin your wheels too fast. The method
known as rocking can help you get out when you
are stuck, but you must use caution.
{CAUTION:
If you let your vehicle’s tires spin at high
speed, they can explode, and you or others
could be injured. And, the transmission or
other parts of the vehicle can overheat.
That could cause an engine compartment
re or other damage. When you are stuck,
spin the wheels as little as possible. Do not
spin the wheels above 35 mph (55 km/h)
as shown on the speedometer.Notice:Spinning the wheels can destroy
parts of your vehicle as well as the tires.
If you spin the wheels too fast while shifting
the transmission back and forth, you can
destroy the transmission.
For information about using tire chains on your
vehicle, seeTire Chains on page 389.
Rocking Your Vehicle to Get It Out
First, turn the steering wheel left and right.
That will clear the area around the front wheels.
Your vehicle has a traction control system that
will activate when the system senses that
the wheels are spinning. SeeTraction Control
System (TCS) on page 241for more information.
Then, with the wheels straight ahead, shift
back and forth between REVERSE (R) and a
forward gear, or with a manual transmission,
between FIRST (1) or SECOND (2) and
REVERSE (R), spinning the wheels as little as
possible. Release the accelerator pedal while
you shift, and press lightly on the accelerator
pedal when the transmission is in gear.
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