engine HUMMER H2 2005 Service Manual

CHARGING SYSTEM FAILURE
On some vehicles, if there is a problem with the
generator and battery charging system, this message
will appear on the DIC, a chime will sound and the
charging system light on the instrument panel cluster
will come on. SeeCharging System Light on page 3-31
for more information. Driving with this problem could
drain your battery. Turn off all unnecessary accessories.
Stop and turn off the vehicle as soon as it is safe to
do so. Have the electrical system checked by your
GM dealer immediately.
CHECK OIL LEVEL
If the oil level in the vehicle is low, this message will
appear on the DIC. Check the oil level and correct it as
necessary. You may need to let the vehicle cool or
warm up and cycle the ignition to be sure this message
will clear. Once the problem is corrected, pressing
any of the four DIC buttons or the trip odometer reset
stem will clear this message from the DIC display. This
message will clear itself after 10 seconds until the
next ignition cycle.
CHECK WASHER FLUID
If the washer uid level is low, this message will appear
on the DIC. Adding washer uid will clear the message.
Pressing any of the four DIC buttons or the trip
odometer reset stem will clear it from the DIC display.
This message will clear itself after 10 seconds until
the next ignition cycle.
DRIVER DOOR AJAR
If the driver’s door is not fully closed and the vehicle is in
a drive gear, this message will appear on the display and
you will hear a chime. Stop and turn off the vehicle, check
the door for obstacles, and close the door again. Check to
see if the message still appears on the DIC. Pressing any
of the four DIC buttons or the trip odometer reset stem
will clear the message from the DIC display.
ENGINE COOLANT HOT
If the cooling system temperature gets hot, this message
will appear in the DIC. Stop the vehicle and let the
engine idle in PARK (P) to allow the coolant to reach a
safe temperature. This message will clear when the
coolant temperature drops to a safe operating
temperature. Pressing any of the four DIC buttons or
the trip odometer reset stem will clear the message from
the DIC display.
3-48

ENGINE OVERHEATED
If the engine cooling system reaches unsafe
temperatures for operation, this message will appear in
the DIC and you will hear a chime. Stop and turn off
the vehicle as soon as it is safe to do so to avoid severe
damage. This message will clear when the engine
has cooled to a safe operating temperature.
FUEL LEVEL LOW
If the fuel level is low, this message will appear on the
DIC and you will hear a chime. Refuel as soon as
possible. Pressing any of the four DIC buttons or the
trip odometer reset stem will clear the message from the
DIC display. It will also clear itself after 10 seconds.
The low fuel light near the fuel gage will still remain on
in either case.
KEYFOB X BATTERY LOW
If a remote keyless entry transmitter battery is low, this
message will appear on the DIC. The battery needs
to be replaced in the transmitter. See “Battery
Replacement” underRemote Keyless Entry System
Operation on page 2-5. Pressing any of the four
DIC buttons or the trip odometer reset stem will clear
the message from the DIC display.
LEFT REAR DOOR AJAR
If the driver’s side rear door is not fully closed and the
vehicle is in a drive gear, this message will appear
on the display and you will hear a chime. Stop and turn
off the vehicle, check the door for obstacles, and
close the door again. Check to see if the message still
appears on the DIC. Pressing any of the four DIC
buttons or the trip odometer reset stem will clear the
message from the DIC display.
LOW COOLANT LEVEL
If your vehicle has a low coolant sensor and the engine
coolant level is low, this message will appear on the
DIC. Adding coolant will clear the message. This
message will clear itself after 10 seconds until the next
ignition cycle.
OIL LIFE RESET
This message will appear on the display for about
10 seconds after resetting the change engine oil
message.
3-49

OIL PRESSURE LOW
If low oil pressure levels occur, this message will be
displayed on the DIC and a chime will sound. Stop the
vehicle as soon as safely possible and do not operate
it until the cause of the low oil pressure has been
corrected. Check your oil as soon as possible and have
your vehicle serviced by your GM dealer.
PASSENGER DOOR AJAR
If the passenger’s door is not fully closed and the
vehicle is in a drive gear, this message will appear on
the display and you will hear a chime. Stop and turn off
the vehicle, check the door for obstacles, and close
the door again. Check to see if the message still
appears on the DIC. Pressing any of the four DIC
buttons or the trip odometer reset stem will clear the
message from the DIC display.
REAR ACCESS OPEN
On the SUV, if the liftgate is open while the ignition is in
RUN, this message will appear on the DIC and you will
hear a chime. Turn off the vehicle and check the liftgate.
Restart the vehicle and check for the message on the DIC
display. Pressing any of the four DIC buttons or the trip
odometer reset stem will clear the message from the DIC
display.On the SUT, if the midgate is open or one or both of the
midgate latches are not fully closed, this message will
appear on the DIC. Turn off the vehicle and check that
the midgate and the latches are closed. Restart the
vehicle and check for the message on the DIC display.
Pressing any of the four DIC buttons or the trip odometer
reset stem will clear the message from the DIC display.
REDUCED ENGINE POWER
This message is displayed when the cooling system
temperature gets too hot and the engine further enters
the engine coolant protection mode.
SeeEngine Overheating on page 5-26for further
information.
You may also see this message when the vehicle
determines a problem with the electronic throttle control.
See your GM dealer for service.
REPLACE LIFTGATE FUSE
This message will be displayed if the liftgate lock
malfunctions and/or the liftgate fuse blows. For more
information on fuses, seeInstrument Panel Fuse Block
on page 5-103andUnderhood Fuse Block on
page 5-107.
If the message returns after replacing the fuse, see your
GM dealer for service.
3-50

SERVICE CHARGING SYSTEM
On some vehicles, if there is a problem with the battery
charging system, this message will appear on the
DIC. The battery will not be charging at an optimal rate
and the vehicle will lose the ability to enter the fuel
economy mode. The vehicle is safe to drive, however
you should have the electrical system checked by
your GM dealer. Pressing any of the four DIC buttons or
the trip odometer reset stem will clear the message
from the DIC display.
TIGHTEN FUEL CAP
If the vehicle’s fuel cap is not tightened properly, this
message may appear along with the check engine light
on the instrument panel cluster. SeeMalfunction Indicator
Lamp on page 3-37. Reinstall the fuel cap, making sure
to fully install the cap. SeeFilling Your Tank on page 5-7.
The diagnostic system can determine if the fuel cap has
been left off or improperly installed. A loose or missing
fuel cap will allow fuel to evaporate into the atmosphere.
A few driving trips with the cap properly installed should
turn the light and message off.
TRACTION ACTIVE
When the traction control system has detected that any
of the vehicle’s wheels are slipping, the traction
control system will activate and this message will appear
on the DIC. SeeTraction Control System (TCS) on
page 4-9for more information.
TRANS HOT IDLE ENGINE
If the transmission uid gets hot, this message will
appear on the DIC along with a continuous chime.
Driving with the transmission uid temperature high can
cause damage to the vehicle. Stop the vehicle and
let it idle to allow the transmission to cool. This message
will clear and the chime will stop when the uid
temperature reaches a safe level.
3-52

Elevated Idle
The elevated idle feature is available on diesel engine
vehicles only. Press the personalization button until
ELEVATED IDLE appears in the display. To select your
personalization for elevated idle, press the select
button while ELEVATED IDLE is displayed on the DIC.
Pressing the select button will scroll through the
following choices:
ELEVATED IDLE: OFF (default):The elevated
idle/exhaust restrictor feature is turned off. See
“Elevated Idle/Exhaust Restrictor” under Starting and
Operating Your Vehicle in your DURAMAX™ Diesel
supplement.
ELEVATED IDLE: ON:The elevated idle/exhaust
restrictor feature is turned on. See “Elevated
Idle/Exhaust Restrictor” under Starting and Operating
Your Vehicle in your DURAMAX™ Diesel supplement.
Choose one of the available options and press the
personalization button while your choice is displayed on
the DIC to select it and move on to the next feature.
Language
To select your personalization for display language,
press the select button while LANGUAGE is displayed
on the DIC. Pressing the select button will scroll through
the following languages:
ENGLISH
FRANCAIS (French)
ESPANOL (Spanish)
Choose one of the available options and press the
personalization button while it is displayed on the DIC to
select it.
If you accidentally choose a language that you do not
want or understand, press and hold the personalization
button and the trip information button at the same
time. The DIC will begin scrolling through the languages
in their particular language. English will be in English,
Francais will be in French and Espanol will be in
Spanish. When you see the language that you would
like, release both buttons. The DIC will then display the
information in the language you chose.
You can also scroll through the different languages
by pressing and holding the trip reset stem for
four seconds, as long as you are in the odometer mode.
3-59

Display Units
Press the personalization button until DISPLAY UNITS
appears in the display. To select English or metric,
press the select button while DISPLAY UNITS is
displayed on the DIC. Pressing the select button will
scroll through the following choices:
DISPLAY UNITS: ENGLISH
DISPLAY UNITS: METRIC
If you choose English, all information will be displayed
in English units. For example, distance in miles and fuel
economy in miles per gallon.
Choose one of the available options and press the
personalization button while it is displayed on the DIC to
select it and end out of the personalization options.
Audio System(s)
Notice:Before adding any sound equipment to
your vehicle, like a tape player, CB radio, mobile
telephone, or two-way radio, make sure that it can
be added by checking with your dealer. Also,
check federal rules covering mobile radio and
telephone units. If sound equipment can be added,
it is very important to do it properly. Added
sound equipment may interfere with the operation
of your vehicle’s engine, radio, or other systems,
and even damage them. Your vehicle’s systems may
interfere with the operation of sound equipment
that has been added improperly.
Figure out which audio system is in your vehicle, nd
out what your audio system can do, and how to operate
all of its controls.
Your vehicle has a feature called Retained Accessory
Power (RAP). With RAP, the audio system can be
played even after the ignition is turned off. SeeRetained
Accessory Power (RAP) on page 2-26for more
information.
3-60

Braking
Braking action involves perception time and
reaction time.
First, you have to decide to push on the brake pedal.
That is perception time. Then you have to bring up your
foot and do it. That is reaction time.
Average reaction time is about three-fourths of a
second. But that is only an average. It might be less
with one driver and as long as two or three seconds or
more with another. Age, physical condition, alertness,
coordination and eyesight all play a part. So do alcohol,
drugs and frustration. But even in three-fourths of a
second, a vehicle moving at 60 mph (100 km/h) travels
66 feet (20 m). That could be a lot of distance in an
emergency, so keeping enough space between
your vehicle and others is important.
And, of course, actual stopping distances vary greatly
with the surface of the road (whether it is pavement
or gravel); the condition of the road (wet, dry, icy); tire
tread; the condition of your brakes; the weight of
the vehicle and the amount of brake force applied.Avoid needless heavy braking. Some people drive
in spurts — heavy acceleration followed by heavy
braking — rather than keeping pace with traffic. This is
a mistake. Your brakes may not have time to cool
between hard stops. Your brakes will wear out much
faster if you do a lot of heavy braking. If you keep pace
with the traffic and allow realistic following distances,
you will eliminate a lot of unnecessary braking.
That means better braking and longer brake life.
If your engine ever stops while you are driving, brake
normally but do not pump your brakes. If you do,
the pedal may get harder to push down. If your engine
stops, you will still have some power brake assist.
But you will use it when you brake. Once the power
assist is used up, it may take longer to stop and
the brake pedal will be harder to push.
4-6

Anti-Lock Brake System (ABS)
Your vehicle has anti-lock brakes. ABS is an advanced
electronic braking system that will help prevent a
braking skid.
When you start your engine and begin to drive away,
your anti-lock brake system will check itself. You
may hear a momentary motor or clicking noise while
this test is going on. This is normal.
If there is a problem with
the anti-lock brake system,
this warning light will
stay on. SeeAnti-Lock
Brake System Warning
Light on page 3-34.
Let us say the road is wet and you are driving safely.
Suddenly, an animal jumps out in front of you. You slam
on the brakes and continue braking. Here is what
happens with ABS:
A computer senses that wheels are slowing down. If
one of the wheels is about to stop rolling, the computer
will separately work the brakes at each front wheel
and at both rear wheels.
4-7

Traction Control System (TCS)
Your vehicle has a Traction Control System (TCS) that
limits wheel spin. This is especially useful in slippery
road conditions. The system operates only if it senses
that any of the wheels are spinning or beginning to lose
traction. When this happens, the system applies the
brakes to limit wheel spin.
The Traction Control System may operate on dry roads
under some conditions. When this happens, you may
notice a reduction in acceleration or a pumping sound.
This is normal and doesn’t mean there’s a problem with
your vehicle. Examples of these conditions include hard
acceleration in a turn, an abrupt upshift or downshift of
the transmission or driving on rough roads.
If your vehicle is in cruise control when the TCS begins
to limit wheel spin, the cruise control will automatically
disengage. When road conditions allow you to safely
use it again, you may re-engage the cruise control. See
Cruise Control on page 3-10.
Another feature of this system is the Traction Control 2
(TC2) mode. TC2 should be selected for improved
traction and system performance when the vehicle is on
loose surfaces such as deep sand or mud.To enter this mode,
press the TC2 button
located on the instrument
panel to the right of
the steering wheel.
TC2 only operates in the following transfer case modes:
4HI Lock
4LO Lock
4LO Lock and Rear Axle Lock
SeeLocking Rear Axle on page 4-10for more
information on the rear axle lock.
It will not operate in 4HI. If the TC2 button is pressed
while in 4HI, the light will ash for about 15 seconds and
then go out. The light should also come on briey
when you turn the ignition key to RUN; if it doesn’t see
your dealer for service.
If you restart your engine, the system reverts to the
standard TCS mode.
4-9

You must wait for the light in the button to stop ashing
and remain illuminated before the rear axle is locked.
Notice:If you try to lock the rear axle while
your vehicle is stuck and the tires are spinning, you
could damage your vehicle’s drivetrain. The
repairs would not be covered by your warranty.
Always lock the rear axle before attempting
situations and/or navigating terrain which could
possibly cause the vehicle to become stuck.
The locking rear axle will be disengaged when the
vehicle’s speed is greater than 20 mph (32 km/h), if the
vehicle’s battery is low and/or the transfer case is
shifted out of 4LO Lock mode.
Notice:If you lock the rear axle while driving on
pavement, you could damage your vehicle’s
drivetrain. The repairs would not be covered by
your warranty. Do not use the locking rear axle on
pavement. If you need four-wheel drive when
traveling on pavement, use only 4HI.
Steering
Power Steering
If you lose power steering assist because the engine
stops or the system is not functioning, you can steer but
it will take much more effort.
Steering Tips
Driving on Curves
It is important to take curves at a reasonable speed.
A lot of the “driver lost control” accidents mentioned on
the news happen on curves. Here is why:
Experienced driver or beginner, each of us is subject to
the same laws of physics when driving on curves.
The traction of the tires against the road surface makes
it possible for the vehicle to change its path when
you turn the front wheels. If there is no traction, inertia
will keep the vehicle going in the same direction. If
you have ever tried to steer a vehicle on wet ice, you
will understand this.
The traction you can get in a curve depends on the
condition of your tires and the road surface, the angle at
which the curve is banked, and your speed. While you are
in a curve, speed is the one factor you can control.
Suppose you are steering through a sharp curve.
Then you suddenly accelerate. Both control
systems — steering and acceleration — have to do their
work where the tires meet the road. Adding the
sudden acceleration can demand too much of those
places. You can lose control. SeeTraction Control
System (TCS) on page 4-9.
What should you do if this ever happens? Ease up on
the accelerator pedal, steer the vehicle the way you
want it to go, and slow down.
4-11