5-24 Instruments and Controls
Fuel System Messages
FUEL CAP
This message displays if the
vehicle's fuel cap is either off or
loose. Pull over as soon as possible
and check to see if the fuel cap is
secure. You may also see the check
engine light on the instrument panel
cluster. If the check engine light
does come on when the fuel cap
was loose, it may take a few driving
trips before the light turns off.
SeeMalfunction Indicator Lamp
on
page 5‑12for more information if
the light still remains on. Press
and release the reset stem to
acknowledge the message and
clear it from the display.
LOW FUEL
This message displays if the level of
fuel in the vehicle is low. Also check
the fuel gauge. See Fuel Gauge
on
page 5‑8for more information.
Refill the fuel tank as soon as
possible.
Lamp Messages
TURN SIGNAL
This message displays when the
turn signal is on for about 1.2 km
(0.75 miles) of travel. Press
and release the reset stem to
acknowledge the message and
clear it from the display.
Ride Control System
Messages
SERVICE STAB (Stability)
SYS (System)
This message displays if there is
a problem with the StabiliTrak®
system. Have the vehicle serviced
by your dealer. See StabiliTrak
System
on page 9‑53for more
information.
STAB (Stability)
SYS (System) OFF
This message displays when the
StabiliTrak®system is turned off.
See StabiliTrak Systemon
page 9‑53for more information.
TRAC (Traction) OFF
This message along with the
traction off light displays when the
Traction Control System (TCS) is
turned off by pressing the TCS
button. See Traction Control System
(TCS)
on page 9‑52and Traction
Control System (TCS)/StabiliTrak®
Lighton page 5‑16for more
information.
9-34 Driving and Operating
Ignition Positions
The ignition switch has four different
positions.
To shift out of P (Park), turn the
ignition to ON/RUN and apply the
regular brake pedal.
Notice:Using a tool to force the
key to turn in the ignition could
cause damage to the switch or
break the key. Use the correct
key, make sure it is all the way in,
and turn it only with your hand.
If the key cannot be turned by
hand, see your dealer. (A) LOCK/OFF:
This position
locks the ignition. It also locks
the transmission on automatic
transmission vehicles. It locks
the steering wheel on manual
transmission vehicles. The key can
only be removed in LOCK/OFF.
On vehicles with an automatic
transmission, the shift lever must be
in P (Park) to turn the ignition switch
to LOCK/OFF.
The steering can bind with the
wheels turned off center. If this
happens, move the steering wheel
from right to left while turning the
key to ACC/ACCESSORY. If this
doesn't work, then the vehicle needs
service.
(B) ACC/ACCESSORY: This is the
position in which you can operate
the electrical accessories or items
plugged into the accessory power
outlets. On automatic transmission
vehicles, this position unlocks the
ignition. On manual transmission
vehicles, it unlocks the ignition and steering wheel. Use this position
if the vehicle must be pushed or
towed.
(C) ON/RUN:
This position can
be used to operate the electrical
accessories and to display some
instrument panel cluster warning
and indicator lights. The switch
stays in this position when the
engine is running. The transmission
is also unlocked in this position on
automatic transmission vehicles.
If you leave the key in the
ACC/ACCESSORY or ON/RUN
position with the engine off, the
battery could be drained. You may
not be able to start the vehicle if the
battery is allowed to drain for an
extended period of time.
(D) START: This is the position that
starts the engine. When the engine
starts, release the key. The ignition
switch returns to ON/RUN for
driving.
Driving and Operating 9-47
Notice:Operating the vehicle
in Four-Wheel-Low Lock above
48 km/h (30 mph) for any
extended period of time could
cause damage to the transfer
case. Do not operate the vehicle
in Four-Wheel-Low Lock above
48 km/h (30 mph) for extended
periods.
4
n Q(Four-Wheel-Low Lock):
This setting delivers extra torque
to all four wheels and is used for
extreme off-road conditions.
If the vehicle has locking axles,
they can be locked for additional
traction in extreme off-road
situations. See Locking Rear Axle
on page 9‑54andLocking Front
Axle on page 9‑55.
Indicator lights in the buttons show
which setting the transfer case is
in. The indicator lights will come
on briefly when the ignition is in
ON/RUN. The If the lights do not
come on, take the vehicle to your
dealer for service. An indicator light will flash while shifting the transfer
case. If the transfer case cannot
make a requested shift, it will return
to the last chosen setting.
If the SERV 4WD message on the
Driver Information Center (DIC)
stays on, take the vehicle to your
dealer for service. See Service 4WD
message under
Driver Information
Center (DIC) on page 5‑18.
Shifting between Four-Wheel High
and Four-Wheel-High Lock
With the vehicle traveling less than
120 km/h (75 mph), press and
release the Four-Wheel High or
Four-Wheel-High Lock button.
It may be necessary to drive
backwards while turning for a
distance of 7.5 m (25 feet) to get
the lock feature to disengage.
Shifting into Four-Wheel Low Lock
Notice: Shifting the transmission
into gear before the indicator
light stops flashing could cause
damage to the transfer case. Always wait until the indicator
light stops flashing before putting
the transmission back in gear.
To shift into Four-Wheel-Low Lock,
the ignition must be in ON/RUN and
the vehicle must be stopped or
moving less than 5 km/h (3 mph)
with the transmission in N (Neutral).
The preferred method for shifting
into Four-Wheel Low is to have
the vehicle moving 1.6 to 3.2 km/h
(1 to 2 mph). Press and release
the Four-Wheel-Low Lock button.
If the vehicle has a manual
transmission, the clutch pedal must
be pressed to the floor while you
press the Four-Wheel-Low Lock
button, or the shift will not be
completed. You must wait for the
Four-Wheel-Low Lock indicator light
to stop flashing and remain lit before
shifting the transmission into gear.
It is normal for the vehicle to have
engagement noise and bump when
shifting between Four-Wheel Low
and Four-Wheel High ranges or
from Neutral.
9-66 Driving and Operating
For customers who do not use
TOP TIER Detergent Gasoline
regularly, one bottle of GM Fuel
System Treatment PLUS, added
to the fuel tank at every engine oil
change, can help clean deposits
from fuel injectors and intake
valves. GM Fuel System Treatment
PLUS is the only gasoline additive
recommended by HUMMER. It is
available at your dealer/retailer.
Gasolines containing oxygenates,
such as ethers and ethanol, and
reformulated gasolines might
be available in your area. We
recommend that you use these
gasolines, if they comply with the
specifications described earlier.
However, E85 (85% ethanol) and
other fuels containing more than
10% ethanol must not be used in
vehicles that were not designed for
those fuels.Notice:
This vehicle was not
designed for fuel that contains
methanol. Do not use fuel
containing methanol. It can
corrode metal parts in the fuel
system and also damage plastic
and rubber parts. That damage
would not be covered under the
vehicle warranty.
Some gasolines that are
not reformulated for low
emissions can contain an
octane-enhancing additive called
methylcyclopentadienyl manganese
tricarbonyl (MMT); ask the attendant
where you buy gasoline whether the
fuel contains MMT. We recommend
against the use of such gasolines.
Fuels containing MMT can reduce
the life of spark plugs and the
performance of the emission control
system could be affected. The
malfunction indicator lamp might
turn on. If this occurs, return to your
dealer/retailer for service.Fuel E85 (85% Ethanol)
The 8th digit of the Vehicle
Identification Number (VIN) shows
the code letter or number that
identifies the vehicle's engine.
The VIN is at the top left of the
instrument panel. See Vehicle
Identification Number (VIN)
on
page 12‑1.
If the vehicle has the 5.3L V8 engine
(VIN Code P), you can use either
unleaded gasoline or ethanol fuel
containing up to 85% ethanol (E85).
In all other engines, use only the
unleaded gasoline described under
Recommended Fuel on page 9‑64.
Only vehicles that have the
5.3L V8 engine (VIN Code P)
can use 85% ethanol fuel (E85).
We encourage the use of E85 in
vehicles that are designed to use it.
The ethanol in E85 is a “renewable”
fuel, meaning it is made from
renewable sources such as corn
and other crops.
Driving and Operating 9-67
Many service stations will not have
an 85% ethanol fuel (E85) pump
available. The U.S. Department of
Energy has an alternative fuels
website (www.eere.energy.gov/afdc/
infrastructure/locator.html) that can
help you find E85 fuel. Those
stations that do have E85 should
have a label indicating ethanol
content. Do not use the fuel if the
ethanol content is greater than 85%.
At a minimum, E85 should meet
ASTM Specification D 5798. By
definition, this means that fuel
labeled E85 will have an ethanol
content between 70% and 85%.
Filling the fuel tank with fuel
mixtures that do not meet ASTM
specifications can affect driveability
and could cause the malfunction
indicator lamp to come on.To ensure quick starts in the
wintertime, the E85 fuel must be
formulated properly for your climate
according to ASTM specification
D 5798. If you have trouble starting
on E85, it could be because the
E85 fuel is not properly formulated
for your climate. If this happens,
switching to gasoline or adding
gasoline to the fuel tank can
improve starting. For good starting
and heater efficiency below 0°C
(32°F), the fuel mix in the fuel tank
should contain no more than 70%
ethanol. It is best not to alternate
repeatedly between gasoline and
E85. If you do switch fuels, it is
recommended that you add as
much fuel as possible
—do not add
less than 11 L (three gallons) when
refueling. You should drive the
vehicle immediately after refueling
for at least 11 km (seven miles) to
allow the vehicle to adapt to the
change in ethanol concentration. E85 has less energy per gallon
than gasoline, so you will need to
refill the fuel tank more often when
using E85 than when you are using
gasoline. See
Filling the Tank
on
page 9‑68.
Notice: Some additives are not
compatible with E85 fuel and can
harm the vehicle's fuel system.
Do not add anything to E85.
Damage caused by additives
would not be covered by the
vehicle warranty.
Notice: This vehicle was not
designed for fuel that contains
methanol. Do not use fuel
containing methanol. It can
corrode metal parts in the fuel
system and also damage plastic
and rubber parts. That damage
would not be covered under the
vehicle warranty.
10-22 Vehicle Care
6. Start the engine and let it rununtil you can feel the upper
radiator hose getting hot. Watch
out for the engine cooling fan.
7. By this time, the coolant level inside the radiator filler neck
might be lower. If the level is
lower, add more of the proper
DEX‐COOL coolant mixture
through the filler neck until the
level reaches the base of the
filler neck.
8. Then replace the pressure cap. At any time during this procedure
if coolant begins to flow out of
the filler neck, reinstall the
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.
Engine Overheating
The vehicle has an indicator to warn
of engine overheating.
A coolant temperature gauge is
displayed on the instrument panel.
See Engine Coolant Temperature
Gauge on page 5‑9.
You may decide not to lift the
hood when this warning appears,
but instead get service help right
away. See Roadside Service
on
page 13‑5.
If you do decide to lift the hood,
make sure the vehicle is parked on
a level surface. Then check to see if the engine
cooling fans are running. If the
engine is overheating, both fans
should be running. If they are not,
do not continue to run the engine
and have the vehicle serviced.
The air conditioning might stop
working if the engine is too hot. This
is normal and helps cool the engine.
Notice:
Engine damage from
running the engine without
coolant is not covered by the
warranty.
Notice: If the engine catches
fire because of being driven
with no coolant, your vehicle can
be badly damaged. The costly
repairs would not be covered by
the vehicle warranty.
10-26 Vehicle Care
Brakes
This vehicle has 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 can come and go or be
heard all the time the vehicle is
moving, except when applying the
brake pedal firmly.
{WARNING
The brake wear warning sound
means that soon the brakes will
not work well. That could lead to
an accident. When the brake
wear warning sound is heard,
have the vehicle serviced.
Notice: Continuing to drive with
worn-out brake pads could result
in costly brake repair. Some driving conditions or climates
can cause a brake squeal when the
brakes are first applied or lightly
applied. This does not mean
something is wrong with the 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 torque
specifications in
Capacities and
Specifications on page 12‑2.
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
that brake service might be
required.
Brake Adjustment
Every time the brakes are applied,
with or without the vehicle moving,
the brakes adjust for wear.
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. The vehicle was designed
and tested with top-quality brake
parts. When parts of the braking
system are replaced, be sure to get
new, approved replacement parts.
If this is not done, the brakes might
not work properly. For example,
installing disc brake pads that are
wrong for the vehicle, can change
the balance between the front and
rear brakes —for the worse. The
braking performance expected can
change in many other ways if the
wrong replacement brake parts are
installed.
INDEX i-5
Fuel (cont.)Fuels in Foreign Countries . . . . 9-65
Gasoline Specifications . . . . . . . 9-65
Gauge . . . . . . . . . . . . . . . . . . . . . . . . . 5-8
Recommended . . . . . . . . . . . . . . . 9-64
Requirements, California . . . . . 9-65
System Messages . . . . . . . . . . . . 5-24
Fuel Economy Driving for Better . . . . . . . . . . . . . 1-18
Full-Size Spare Tire . . . . . . . . . . 10-85
Fuses Engine CompartmentFuse Block . . . . . . . . . . . . . . . . 10-39
Fuses and Circuit
Breakers . . . . . . . . . . . . . . . . . . 10-39
G
Garage Door Opener . . . . . . . . . . 5-26Programming . . . . . . . . . . . . . . . . . 5-26
Gasoline
Specifications . . . . . . . . . . . . . . . . . 9-65 Gauges
Engine Coolant
Temperature . . . . . . . . . . . . . . . . . 5-9
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8
Odometer . . . . . . . . . . . . . . . . . . . . . . 5-8
Speedometer . . . . . . . . . . . . . . . . . . 5-8
Tachometer . . . . . . . . . . . . . . . . . . . . 5-8
Trip Odometer . . . . . . . . . . . . . . . . . 5-8
Warning Lights and Indicators . . . . . . . . . . . . . . . . . . . . 5-6
General Information
Service and Maintenance . . . . . 11-1
Towing . . . . . . . . . . . . . . . . . . . . . . . . 9-70
Vehicle Care . . . . . . . . . . . . . . . . . . 10-2
Glove Box . . . . . . . . . . . . . . . . . . . . . . 4-1
H
Halogen Bulbs . . . . . . . . . . . . . . . . 10-35
Hazard Warning Flashers . . . . . . . 6-5
Head Restraints . . . . . . . . . . . . . . . . 3-2 Headlamps . . . . . . . . . . . . . . . . . . . 10-35
Aiming . . . . . . . . . . . . . . . . . . . . . . 10-33
Automatic . . . . . . . . . . . . . . . . . . . . . . 6-4
Bulb Replacement . . . . . . . . . . 10-35
Daytime Running
Lamps (DRL) . . . . . . . . . . . . . . . . . 6-3
Flash-to-Pass . . . . . . . . . . . . . . . . . . 6-3
High-Beam On Light . . . . . . . . . . 5-17
High/Low Beam Changer . . . . . . 6-3
Heated Front Seats . . . . . . . . . . . . . 3-6
Heater Engine Coolant . . . . . . . . . . . . . . . 9-36
High-Beam On Light . . . . . . . . . . . 5-17
Highway Hypnosis . . . . . . . . . . . . . 9-22
Hill and Mountain Roads . . . . . . . 9-23
Hill Start Assist (HSA) . . . . . . . . . 9-52
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . 10-5
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2
How to Wear Safety Belts Properly . . . . . . . . . . . . . . . . . . . . . . 3-15
Hydraulic Clutch . . . . . . . . . . . . . . 10-16