open hood 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

Checking Things Under
the Hood
{CAUTION:
An electric fan under the hood can start up
and injure you even when the engine is not
running. Keep hands, clothing, and tools away
from any underhood electric fan.
{CAUTION:
Things that burn can get on hot engine parts
and start a re. These include liquids like fuel,
oil, coolant, brake uid, windshield washer and
other uids, and plastic or rubber. You or
others could be burned. Be careful not to drop
or spill things that will burn onto a hot engine.
Hood Release
To open the hood, do the following:
1. Pull the handle with
this symbol on it. It is
located inside the
vehicle on the lower
left side of the
instrument panel.
2. Release the secondary latch on the hood. It is
located below the front center of the hood.
3. Lift the hood.
Before closing the hood, be sure all the ller caps are
on properly. Then pull the hood down and close it rmly.
5-11

Engine Compartment Overview
When you open the hood on the 3.7L engine, this is what you will see:
5-12

When you open the hood on the 5.3L engine, this is what you will see:
5-14

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. You
or others could be badly burned. Stop your
engine if it overheats, and get out of the
vehicle until the engine is cool.
Notice:If your engine catches re because you
keep driving with no coolant, your vehicle can
be badly damaged. The costly repairs would not be
covered by your warranty.
If No Steam Is Coming From Your
Engine
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. See “Driving on Grades” under
Towing a Trailer on page 4-50.
If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. In heavy traffic, let the engine idle in NEUTRAL
while stopped. If it is safe to do so, pull off the
road, shift to PARK (P) or NEUTRAL and let the
engine idle.
2. Turn off the air conditioning.
3. Turn on your heater to full hot at the highest fan
speed and open the windows as necessary.
5-30

4. Open the hoods and locate the batteries on both
vehicles. You will use the positive (+) battery terminal
and the remote negative (−) jump starting terminal to
jump start your vehicle. To access the positive (+)
battery terminal, open the terminal cover. See
Engine Compartment Overview on page 5-12for
more information on the terminal locations.
{CAUTION:
Using a match near a battery can cause battery
gas to explode. People have been hurt doing
this, and some have been blinded. Use a
ashlight if you need more light.
Be sure the batteries have enough water. You
do not need to add water to the ACDelco
®
battery (or batteries) installed in your new
vehicle. But if a battery has ller caps, be sure
the right amount of uid is there. If it is low,
add water to take care of that rst. If you do
not, explosive gas could be present.
Battery uid contains acid that can burn you.
Do not get it on you. If you accidentally get it
in your eyes or on your skin, ush the place
with water and get medical help immediately.
{CAUTION:
Fans or other moving engine parts can injure
you badly. Keep your hands away from moving
parts once the engine is running.
5. Check that the jumper cables do not have loose or
missing insulation. If they do, you could get a
shock. The vehicles could be damaged too.
Before you connect the cables, here are some
basic things you should know. Positive (+) will go to
positive (+) or to a remote positive (+) terminal if
the vehicle has one. Negative (−) will go to a heavy,
unpainted metal engine part or to a remote
negative (−) terminal if the vehicle has one.
Do not connect positive (+) to negative (−)oryou
will get a short that would damage the battery
and maybe other parts too. And do not connect the
negative (−) cable to the negative (−) terminal on
the dead battery because this can cause sparks.
5-43

To adjust the vertical aim:
1. Open the hood. SeeHood Release on page 5-11
for more information.
2. Find the aim dot on the lens of the headlamp.3. Record the distance from the ground to the aim dot
on the headlamp.
4. At a wall, measure from the ground upward the
recorded distance from Step 2 and mark it.
5. Draw or tape a horizontal line the width of the
vehicle at the wall where it was marked it Step 4.
Notice:Do not cover a headlamp to improve beam
cut-off when aiming. Covering a headlamp may
cause excessive heat build-up which may cause
damage to the headlamp.
6. Turn on the headlamps and place a piece of
cardboard or equivalent in front of the headlamp not
being aimed. This should allow only the beam of
light from the headlamp being aimed to be seen on
the wall.
5-47

Bulb Replacement
For the proper type of replacement bulbs, see
Replacement Bulbs on page 5-52.
For any bulb changing procedure not listed in this
section, contact your dealer/retailer.
Halogen Bulbs
{CAUTION:
Halogen bulbs have pressurized gas inside and
can burst if you drop or scratch the bulb. You or
others could be injured. Be sure to read and
follow the instructions on the bulb package.
Headlamps
To replace a headlamp bulb:
1. Open the hood. SeeHood Release on page 5-11
for more information.
2. Reach in and access the headlamp bulb socket
from inside the engine compartment.3. Turn the bulb socket counterclockwise to remove it
from the headlamp assembly and pull it straight out.
4. Unplug the electrical connector by pushing
the release tab and pulling the bulb socket out.
5. Replace with a new bulb socket.
6. Reinstall the electrical connector.
7. Reinstall the new bulb socket into the headlamp
assembly and turn it clockwise to secure.
8. Close the hood.
5-49