warning HUMMER H3 2007 Service Manual

What to Use
Use a mixture of one-half clean, drinkable water
and one-half DEX-COOL®coolant which will
not damage aluminum parts. If you use this coolant
mixture, you do not need to add anything else.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can
boil before the proper coolant mixture will.
Your vehicle’s coolant warning system is
set for the proper coolant mixture. With
plain water or the wrong mixture, your
engine could get too hot but you would
not get the overheat warning. Your engine
could catch re and you or others could
be burned. Use a 50/50 mixture of clean,
drinkable water and the proper coolant.Notice:If you use an improper coolant
mixture, your engine could overheat and be
badly damaged. The repair cost would not be
covered by your warranty. Too much water
in the mixture can freeze and crack the engine,
radiator, heater core, and other parts.
Notice:If you use extra inhibitors and/or
additives in your vehicle’s cooling system,
you could damage your vehicle. Use only the
proper mixture of the engine coolant listed
in this manual for the cooling system.
SeeRecommended Fluids and Lubricants
on page 440for more information.
336

CAUTION: (Continued)
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 297.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.
If you no longer have the overheat warning, you
can drive. Just to be safe, drive slower for
about 10 minutes. If the warning does not come
back on, you can drive normally.
If the warning continues, pull over, stop, and park
your vehicle right away.
If there is still no sign of steam, idle the engine for
three minutes while you are parked. Push down
the accelerator until the engine speed is about
twice as fast as normal idle speed for at least three
minutes while you are parked. If you still have
the warning, turn off the engine and get everyone
out of the vehicle until it cools down.
You may decide not to lift the hood but to get
service help right away.
339

How to Add Coolant to the Coolant
Recovery Tank
If you have not found a problem yet, but the
coolant level is not at the FULL COLD mark,
add a 50/50 mixture of clean, drinkable water and
DEX-COOL
®engine coolant at the coolant
recovery tank. SeeEngine Coolant on page 335
for more information.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can
boil before the proper coolant mixture will.
Your vehicle’s coolant warning system is
set for the proper coolant mixture. With
plain water or the wrong mixture, your
engine could get too hot but you would
not get the overheat warning. Your engine
could catch re and you or others could
be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.Notice:In cold weather, water can freeze and
crack the engine, radiator, heater core and
other parts. Use the recommended coolant and
the proper coolant mixture.
{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.
When the coolant in the coolant recovery tank is
at the FULL COLD mark, start your vehicle.
If the overheat warning continues, there is one
more thing you can try. Add the proper mixture
directly to the radiator, but be sure the cooling
system is cool before you do it.
342

Brake Wear
Your vehicle has four-wheel disc brakes.
Disc brake pads have built-in wear indicators that
make a high-pitched warning sound when the
brake pads are worn and new pads are needed.
The sound may come and go or be heard all
the time your vehicle is moving, except when you
are pushing on the brake pedal rmly.
{CAUTION:
The brake wear warning sound means that
soon the brakes will not work well. That
could lead to an accident. When you hear
the brake wear warning sound, have your
vehicle serviced.
Notice:Continuing to drive with worn-out
brake pads could result in costly brake repair.
Some driving conditions or climates may cause
a brake squeal when the brakes are rst applied or
lightly applied. This does not mean something is
wrong with your brakes.Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated,
inspect brake pads for wear and evenly tighten
wheel nuts in the proper sequence to GM torque
specications.
Brake linings should always be replaced as
complete axle sets.
Brake Pedal Travel
See your dealer if the brake pedal does not
return to normal height, or if there is a rapid
increase in pedal travel. This could be a sign
of brake trouble.
Brake Adjustment
Every time you make a brake stop, your disc
brakes adjust for wear.
350

Replacing Brake System Parts
The braking system on a vehicle is complex. Its
many parts have to be of top quality and work well
together if the vehicle is to have really good
braking. Your vehicle was designed and tested with
top-quality GM brake parts. When you replace parts
of your braking system — for example, when your
brake linings wear down and you need new ones
put in — be sure you get new approved GM
replacement parts. If you do not, your brakes may
no longer work properly. For example, if someone
puts in brake linings that are wrong for your vehicle,
the balance between your front and rear brakes can
change — for the worse. The braking performance
you have come to expect can change in many other
ways if someone puts in the wrong replacement
brake parts.
Battery
Your vehicle has a maintenance free battery.
When it is time for a new battery, get
one that has the replacement number shown on
the original battery’s label. We recommend
an ACDelco
®replacement battery. SeeEngine
Compartment Overview on page 322for
battery location.
Warning:Battery posts, terminals, and related
accessories contain lead and lead compounds,
chemicals known to the State of California
to cause cancer and reproductive harm. Wash
hands after handling.
351

How to Check
Use a good quality pocket-type gage to check tire
pressure. You cannot tell if your tires are
properly inated simply by looking at them. Radial
tires may look properly inated even when they
are underinated. Check the tire’s ination
pressure when the tires are cold. Cold means your
vehicle has been sitting for at least three hours
or driven no more than 1 mile (1.6 km).
Remove the valve cap from the tire valve stem.
Press the tire gage rmly onto the valve to
get a pressure measurement. If the cold tire
ination pressure matches the recommended
pressure on the Tire and Loading Information
label, no further adjustment is necessary. If the
ination pressure is low, add air until you reach the
recommended amount.
If you overll the tire, release air by pushing on
the metal stem in the center of the tire valve.
Recheck the tire pressure with the tire gage.
Be sure to put the valve caps back on the valve
stems. They help prevent leaks by keeping out dirt
and moisture.
Tire Pressure Monitor System
Your vehicle has a Tire Pressure Monitor System
(TPMS). This system uses radio and sensor
technology to check tire pressure levels. TPMS
sensors are mounted onto each tire and wheel
assembly on your vehicle, including the spare tire.
The TPMS sensors monitor the air pressure in
your vehicle’s tires and transmit the tire pressure
readings to a receiver located in the vehicle.
When a low tire pressure condition is detected,
the TPMS will illuminate the low tire pressure
warning light located in the instrument panel
cluster, and at the same time display the LOW
TIRE warning message on the Driver Information
Center (DIC). The low tire pressure warning
light and the LOW TIRE warning message appear
at each ignition cycle until the tires are inated
to the correct ination pressure.
376

For additional information and details about the
DIC operation and displays seeDIC Controls and
Displays on page 192andDIC Warnings and
Messages on page 196.
You may notice, during cooler weather conditions,
that the low tire pressure warning light and the
DIC LOW TIRE message may come on when the
vehicle is rst started, and then turn off as you
start to drive. This may be an early indicator that
the air pressure in the tire(s) is getting low
and needs to be inated to the proper pressure.
Each tire, including the spare (if provided), should
be checked monthly when cold and inated to
the ination pressure recommended by the vehicle
manufacturer on the vehicle placard or tire
ination pressure label. (If your vehicle has tires of
a different size than the size indicated on the
vehicle placard or tire ination pressure label, you
should determine the proper tire ination
pressure for those tires.)As an added safety
feature, your vehicle
has been equipped with
a tire pressure
monitoring system
(TPMS) that illuminates
a low tire pressure
telltale when one
or more of your tires is
signicantly
under-inated.
Accordingly, when the low tire pressure telltale
illuminates, you should stop and check your tires
as soon as possible, and inate them to the
proper pressure. Driving on a signicantly
under-inated tire causes the tire to overheat and
can lead to tire failure. Under-ination also
reduces fuel efficiency and tire tread life, and may
affect the vehicle’s handling and stopping ability.
Please note that the TPMS is not a substitute for
proper tire maintenance, and it is the driver’s
responsibility to maintain correct tire pressure, even
if under-ination has not reached the level to trigger
illumination of the TPMS low tire pressure telltale.
377

TPMS Sensor Identication Codes
Each TPMS sensor has a unique identication
code. Any time you replace one or more of
the TPMS sensors, install the spare tire onto your
vehicle, or rotate your vehicle’s tires, the
identication codes will need to be matched to the
new tire/wheel position. The sensors are
matched to the tire/wheel positions in the following
order: driver’s side front tire, passenger’s side
front tire, passenger’s side rear tire, and driver’s
side rear tire using a TPMS diagnostic tool.
See your dealer for service.
The TPMS sensors may also be matched to each
tire/wheel position by increasing or decreasing
the tire’s air pressure. If increasing the tire’s
air pressure, do not exceed the maximum ination
pressure indicated on the tire’s sidewall.
You will have one minute to match the rst
tire/wheel position, and ve minutes overall, to
match all four tire/wheel positions.If it takes longer than one minute, to match the
rst tire and wheel, or more than ve minutes
to match all four tire and wheel positions
the matching process stops and you will need to
start over.
The TPMS sensor matching procedure is
outlined below:
1. Set the parking brake.
2. Turn the ignition switch to ON with the
engine off.
3. Turn the exterior lamp switch from AUTO to
ON four times within three seconds. A double
horn chirp will sound and the TPMS low
tire warning light will begin to ash. The
double horn chirp and ashing TPMS warning
light indicates the TPMS matching process
has started. The TPMS warning light should
continue ashing throughout the matching
procedure. The SERV TPM message will be
displayed on the Driver Information
Center (DIC).
4. Start with the driver’s side front tire.
379

5. Remove the valve cap from the valve cap
stem. Activate the TPMS sensor by
increasing or decreasing the tire’s air pressure
for 10 seconds, then stop and listen for a
single horn chirp. The single horn chirp should
sound within 15 seconds, conrming that
the sensor identication code has been
matched to this tire and wheel position. If you
do not hear the conrming single horn
chirp, you will need to start over with step
number one. To let air-pressure out of a tire
you can use the pointed end of the valve cap,
a pencil-style air pressure gage, or a key.
6. Proceed to the passenger’s side front tire,
and repeat the procedure in Step 5.
7. Proceed to the passenger’s side rear tire,
and repeat the procedure in Step 5.8. Proceed to the driver’s side rear tire, and
repeat the procedure in Step 5.
9. After hearing the conrming horn chirp
for the left rear tire, check to see if
the TPMS warning light is still ashing.
If it is, turn the ignition switch to LOCK.
If the TPMS warning light is not ashing,
the ve minute time limit has passed and
you will need to start the process
over beginning with Step 1.
10. Set all four tires to the recommended air
pressure level as indicated on the Tire
and Loading Information label.
11. Put the valve caps back on the valve stems.
380

Vehicles equipped with a tire pressure monitoring
system may give an inaccurate low-pressure
warning if non-TPC spec rated tires are installed
on your vehicle. Non-TPC Spec rated tires
may give a low-pressure warning that is higher or
lower than the proper warning level you would
get with TPC Spec rated tires. SeeTire Pressure
Monitor System on page 376.
Your vehicle’s original equipment tires are listed
on the Tire and Loading Information Label.
This label is attached to the vehicle’s center pillar
(B-pillar). SeeLoading Your Vehicle on page 289,
for more information about the Tire and Loading
Information Label.
Different Size Tires and Wheels
If you add wheels or tires that are a different size
than your original equipment wheels and tires,
this may affect the way your vehicle performs,
including its braking, ride and handling
characteristics, stability, and resistance to rollover.
Additionally, if your vehicle has electronic
systems such as, anti-lock brakes, traction control,
and electronic stability control, the performance
of these systems can be affected.
{CAUTION:
If you add different sized wheels, your
vehicle may not provide an acceptable
level of performance and safety if tires
not recommended for those wheels are
selected. You may increase the chance
that you will crash and suffer serious
injury. Only use GM specic wheel and
tire systems developed for your vehicle,
and have them properly installed by a
GM certied technician.
SeeBuying New Tires on page 383and
Accessories and Modications on page 314for
additional information.
385