check engine HUMMER H3 2007 Owner's Guide

If you do it yourself, be sure to follow all the
instructions here, or you could get a false reading
on the dipstick.
Notice:Too much or too little uid can
damage your transmission. Too much can
mean that some of the uid could come out
and fall on hot engine parts or exhaust system
parts, starting a re. Too little uid could
cause the transmission to overheat. Be sure
to get an accurate reading if you check
your transmission uid.
Wait at least 30 minutes before checking the
transmission uid level if you have been driving:
When outside temperatures are above
90°F (32°C).
At high speed for quite a while.
In heavy traffic — especially in hot weather.
While pulling a trailer.
To get the right reading, the uid should
be at normal operating temperature, which is
180°F to 200°F (82°C to 93°C).Get the vehicle warmed up by driving about
15 miles (24 km) when outside temperatures are
above 50°F (10°C). If it is colder than 50°F (10°C),
drive the vehicle in THIRD (3) until the engine
temperature gage moves and then remains steady
for 10 minutes.
A cold uid check can be made after the vehicle has
been sitting for eight hours or more with the engine
off, but this is used only as a reference. Let the
engine run at idle for ve minutes if outside
temperatures are 50°F (10°C) or more. If it is colder
than 50°F (10°C), you may have to idle the engine
longer. Should the uid level be low during this cold
check, you must check the uid hot before adding
uid. Checking the uid hot will give you a more
accurate reading of the uid level.
Checking the Fluid Level
Prepare your vehicle as follows:
1. Park your vehicle on a level place. Keep the
engine running.
2. With the parking brake applied, place the shift
lever in PARK (P).
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3. With your foot on the brake pedal, move the
shift lever through each gear range, pausing
for about three seconds in each range.
Then, position the shift lever in PARK (P).
4. Let the engine run at idle for three minutes
or more.
Then, without shutting off the engine, follow
these steps:
1. Flip the handle up and then pull out the
dipstick and wipe it with a clean rag or
paper towel.
The automatic
transmission dipstick
handle with this symbol
on it is located in the
engine compartment on
the passenger’s side
of the vehicle.
SeeEngine Compartment Overview on
page 322for more information on location.
2. Push it back in all the way, wait three seconds
and then pull it back out again.3. Check both sides of the dipstick, and read the
lower level. The uid level must be in the
COLD area, below the cross-hatched area, for
a cold check or in the HOT or cross-hatched
area for a hot check. Be sure to keep the
dipstick pointed down to get an accurate
reading.
4. If the uid level is in the acceptable range,
push the dipstick back in all the way; then
ip the handle down to lock the dipstick
in place.
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How to Add Automatic
Transmission Fluid
Refer to the Maintenance Schedule to determine
what kind of transmission uid to use. See
Recommended Fluids and Lubricants on page 440.
Add uid only after checking the transmission
uid while it is hot. A cold check is used only
as a reference. If the uid level is low, add only
enough of the proper uid to bring the level up to
the HOT area for a hot check. It does not take
much uid, generally less than one pint (0.5 L).
Do not overll.
Notice:Use of the incorrect automatic
transmission uid may damage your vehicle,
and the damages may not be covered by
your warranty. Always use the automatic
transmission uid listed inRecommended
Fluids and Lubricants on page 440.
After adding uid, recheck the uid level as
described under “How to Check Automatic
Transmission Fluid,” earlier in this section.
When the correct uid level is obtained, push
the dipstick back in all the way; then ip the
handle down to lock the dipstick in place.
Manual Transmission Fluid
When to Check
A good time to have it checked is when the
engine oil is changed. However, the uid in your
manual transmission does not require changing.
How to Check
Because this operation can be a little difficult,
you may choose to have this done at your
GM dealership service department.
If you do it yourself, be sure to follow all the
instructions here, or you could get a false reading.
Notice:Too much or too little uid can
damage your transmission. Too little uid
could cause the transmission to overheat. Be
sure to get an accurate reading if you check
your transmission uid.
Check the uid level only when your engine is off,
the vehicle is parked on a level place and the
transmission is cool enough for you to rest your
ngers on the transmission case.
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Hydraulic Clutch
The hydraulic clutch linkage in your vehicle is
self-adjusting. The clutch master cylinder reservoir
is lled with hydraulic clutch uid.
The hydraulic clutch
uid reservoir cap has
this symbol on it.
SeeEngine
Compartment Overview
on page 322for
reservoir location.
It is not necessary to regularly check clutch uid
unless you suspect there is a leak in the system.
Adding uid will not correct a leak.
A uid loss in this system could indicate a
problem. Have the system inspected and repaired.
When to Check and What to Use
Refer to the Maintenance Schedule to determine
how often you should check the uid level in
your clutch master cylinder reservoir and for the
proper uid. SeeRecommended Fluids and
Lubricants on page 440.
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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.
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Checking Coolant
The coolant recovery
tank cap has this
symbol on it.
It is located toward the rear of the engine
compartment on the passenger’s side of the
vehicle. SeeEngine Compartment Overview on
page 322for more information on location.
The vehicle must be on a level surface. When
your engine is cold, the coolant level should be
at FULL COLD, or a little higher. When your
engine is warm, the level could be above the
FULL COLD level.
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.
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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)
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Engine Fan Noise
This vehicle has a clutched engine cooling fan.
When the clutch is engaged, the fan spins faster to
provide more air to cool the engine. In most
everyday driving conditions, the clutch is not
engaged. This improves fuel economy and reduces
fan noise. Under heavy vehicle loading, trailer
towing and/or high outside temperatures, the
fan speed increases when the clutch engages.
So you may hear an increase in fan noise.
This is normal and should not be mistaken as the
transmission slipping or making extra shifts. It
is merely the cooling system functioning properly.
The fan will slow down when additional cooling
is not required and the clutch disengages.
You may also hear this fan noise when you start
the engine. It will go away as the fan clutch
disengages.
Power Steering Fluid
SeeEngine
Compartment Overview
on page 322for
reservoir location.
When to Check Power Steering Fluid
It is not necessary to regularly check power
steering uid unless you suspect there is a leak
in the system or you hear an unusual noise.
A uid loss in this system could indicate a problem.
Have the system inspected and repaired.
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How to Check Power Steering Fluid
1. Turn the key off and let the engine
compartment cool down.
2. Wipe the cap and the top of the reservoir clean.
3. Unscrew the cap and wipe the dipstick with a
clean rag.
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 440.
Always use the proper uid. Failure to use the
proper uid can cause leaks and damage hoses
and seals.
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. See
Engine Compartment
Overview on page 322
for reservoir location.
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So, it is not a good idea to top off your brake uid.
Adding brake uid will not correct a leak. If you
add uid when your linings are worn, then you will
have too much uid when you get new brake
linings. You should add or remove brake uid, as
necessary, only when work is done on the
brake hydraulic system.
{CAUTION:
If you have too much brake uid, it can
spill on the engine. The uid will burn if
the engine is hot enough. You or others
could be burned, and your vehicle could
be damaged. Add brake uid only when
work is done on the brake hydraulic
system. See “Checking Brake Fluid” in
this section.
Refer to the Maintenance Schedule to determine
when to check your brake uid. SeeScheduled
Maintenance on page 429.
Checking Brake Fluid
You can check the brake uid without taking off
the cap.
Look at the brake uid reservoir. The uid level
should be above MIN. If it is not, have your brake
system checked to see if there is a leak.
After work is done on the brake hydraulic system,
make sure the level is above the MIN but not
over the MAX mark.
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