Page 311 of 472
The trailer towing harness contains the following trailer
circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Taillamps
White: Ground
Light Green: Back-up Lamps
Light Blue: Center High-Mounted
Stoplamp (CHMSL)
Red: Battery Feed
Dark Blue: Trailer BrakeA jumper harness for an electric trailer brake controller
and a trailer battery feed fuse may be included with
this trailering package. See “Instrument Panel Jumper
Wiring Harness” later in this section.
If you need to tow a light-duty trailer with a standard
four-way, round pin connector, an adapter may be
included. See “Four-Wire Harness Adapter” later in this
section.
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Instrument Panel Jumper Wiring Harness
Notice:If your vehicle has factory or
dealer-installed HUMMER off-road lamps, the place
where an electric trailer brake connection must
be made is already in use. Do not attempt to
double-up or “piggyback” the connection, because
this could cause a failure or damage to your
vehicle, the electric trailer brake system, or both. If
you want to connect a trailer with electric brakes
to your vehicle, see your dealer to disconnect
the off-road lamps. Also, readAdd-On Electrical
Equipment on page 5-101for more information.This harness may be included with your vehicle as part
of the heavy-duty trailer wiring package.
{CAUTION:
Be sure to use only the correct trailer brake
harness, the one intended for use on your
vehicle. If you use some other trailer brake
harness, even if it seems to t, your trailer
brakes may not work at all. You could have a
crash in which you or others could be injured.
Use only the trailer brake harness intended for
your vehicle. If it is no longer available to you,
be sure to get a proper replacement from your
dealer.
This harness is for an electric brake controller and
includes a trailer battery feed fuse. It should be installed
by your dealer or a quali ed service center.
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Service............................................................5-3
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside of Your
Vehicle......................................................5-5
Fuel................................................................5-5
Gasoline Octane............................................5-5
Gasoline Speci cations....................................5-5
California Fuel...............................................5-6
Additives.......................................................5-6
Fuels in Foreign Countries...............................5-7
Filling Your Tank............................................5-7
Filling a Portable Fuel Container.......................5-9
Checking Things Under the Hood....................5-10
Hood Release..............................................5-10
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-14
Engine Air Cleaner/Filter................................5-19
Automatic Transmission Fluid.........................5-21
Engine Coolant.............................................5-24
Coolant Surge Tank Pressure Cap..................5-27
Engine Overheating.......................................5-27
Cooling System............................................5-30Engine Fan Noise.........................................5-35
Power Steering Fluid.....................................5-36
Windshield Washer Fluid................................5-37
Brakes........................................................5-38
Battery........................................................5-42
Jump Starting...............................................5-43
All-Wheel Drive..............................................5-48
Rear Axle.......................................................5-50
Front Axle......................................................5-51
Bulb Replacement..........................................5-52
Halogen Bulbs..............................................5-52
Headlamps..................................................5-52
Front Turn Signal and Parking Lamps..............5-53
Sidemarker Lamps........................................5-54
Daytime Running Lamps................................5-54
Roof Marker Lamps......................................5-55
Center High-Mounted Stoplamp (CHMSL).........5-57
Taillamps.....................................................5-57
Replacement Bulbs.......................................5-58
Windshield Wiper Blade Replacement..............5-59
Section 5 Service and Appearance Care
5-1
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A. Coolant Surge Tank. SeeCooling System on
page 5-30andCoolant Surge Tank Pressure Cap
on page 5-27.
B. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-19.
C. Windshield Washer Fluid Reservoir. SeeWindshield
Washer Fluid on page 5-37.
D. Engine Oil Fill. SeeEngine Oil on page 5-14.
E. Engine Oil Dipstick. SeeEngine Oil on page 5-14.
F. Automatic Transmission Dipstick. SeeAutomatic
Transmission Fluid on page 5-21.
G. Fan. SeeCooling System on page 5-30andEngine
Fan Noise on page 5-35.H. Remote Negative (−) Terminal (GND). SeeJump
Starting on page 5-43.
I. Power Steering Fluid Reservoir (Out of View). See
Power Steering Fluid on page 5-36.
J. Remote Positive (+) Terminal. SeeJump Starting on
page 5-43.
K. Brake Fluid Reservoir. SeeBrakes on page 5-38.
L. Underhood Fuse Block. See “Underhood Fuse Block”
underFuses and Circuit Breakers on page 5-102.
M. Battery. SeeBattery on page 5-42.
Before closing the hood, be sure all ller caps are on
properly. Pull down the hood and close it rmly.
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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.
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 new vehicle comes with a maintenance free
ACDelco®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
®
battery. SeeEngine Compartment Overview on
page 5-12for 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.
Vehicle Storage
If you are not going to drive your vehicle for 25 days or
more, remove the black, negative (−) cable from the
battery. This will help keep your battery from
running down.
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{CAUTION:
Batteries have acid that can burn you and gas
that can explode. You can be badly hurt if you
are not careful. SeeJump Starting on
page 5-43for tips on working around a battery
without getting hurt.
Contact your dealer to learn how to prepare your
vehicle for longer storage periods.
Also, for your audio system, seeTheft-Deterrent
Feature on page 3-88.
Jump Starting
If your battery has run down, you may want to use
another vehicle and some jumper cables to start your
vehicle. But please use the following steps to do it
safely.
{CAUTION:
Batteries can hurt you. They can be dangerous
because:
They contain acid that can burn you.
They contain gas that can explode or
ignite.
They contain enough electricity to
burn you.
If you do not follow these steps exactly, some
or all of these things can hurt you.
Notice:Ignoring these steps could result in costly
damage to your vehicle that would not be covered
by your warranty.
Trying to start your vehicle by pushing or pulling it
will not work, and it could damage your vehicle.
1. Check the other vehicle. It must have a 12-volt
battery with a negative ground system.
Notice:If the other vehicle’s system is not a 12-volt
system with a negative ground, both vehicles can
be damaged. Only use vehicles with 12-volt systems
with negative grounds to jump start your vehicle.
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2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles aren’t touching
each other. If they are, it could cause a ground
connection you don’t want. You wouldn’t be able to
start your vehicle, and the bad grounding could
damage the electrical systems.
To avoid the possibility of the vehicles rolling, set
the parking brake rmly on both vehicles involved in
the jump start procedure. Put an automatic
transmission in PARK (P) or a manual transmission
in NEUTRAL before setting the parking brake.
Notice:If you leave your radio or other accessories
on during the jump starting procedure, they could
be damaged. The repairs would not be covered
by your warranty. Always turn off your radio and
other accessories when jump starting your vehicle.
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or accessory power outlets. Turn off the radio
and all lamps that aren’t needed. This will avoid
sparks and help save both batteries. And it could
save your radio!4. Open the hoods and locate the positive (+) and
negative (−) terminal locations of the other vehicle.
Your vehicle has a remote positive (+) jump
starting terminal and a remote negative (−) jump
starting terminal. You should always use these
remote terminals instead of the terminals on the
battery.
The remote positive (+)
terminal is located near the
engine accessory drive
bracket. On some vehicles,
the terminal may be
covered under under a red
plastic cover. To access
the remote positive (+)
terminal, open the
red plastic cover.
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The remote negative (−)
terminal is located on
the engine accessory
drive bracket and is
marked GND.
SeeEngine Compartment Overview on page 5-12
for more information on location.
{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 battery has enough water. You do
not need to add water to the ACDelco
®battery
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.
5-45