2008 HUMMER H2 towing

Trailer Wiring Harness
Heavy-Duty Trailer Wiring Harness
Package
Your vehicle is equipped with the seven-wire trailer
towing harness. This harness with a seven-pin universal
trailer connector is attached to a bracket on the hitch
platform.The seven-wire 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
Red/Black: Battery Feed*
Dark Blue: Trailer Brake*
*There is a location in the Underhood Fuse Block for
these circuits, but they are not connected. They should
be connected, and proper fuses installed, by your
dealer/retailer or a qualied service center.
If you are charging a remote (non-vehicle) battery, press
the Tow/Haul mode button located at the end of the shift
lever. This will boost the vehicle system voltage and
properly charge the battery.
4-66

Electric Brake Control Wiring
Provisions
These wiring provisions are included with your vehicle
as part of the trailer wiring package. These provisions
are for an electric brake controller. The instrument panel
contains blunt cut wires near the data link connector
for the trailer brake controller. The harness contains the
following wires:
Dark Blue: Brake Signal to Trailer Connector
Red/Black: Battery
Light Blue/White: Brake Switch
White: Ground
It should be installed by your dealer/retailer or a
qualied service center.
Trailer Recommendations
You must subtract your hitch loads from the Cargo
Weight Rating (CWR). CWR is the maximum weight of
the load your vehicle can carry. It doesn’t include the
weight of the people inside, but you can gure about
150 lbs. (68 kg) for each seat. The total cargo load must
not be more than your vehicles CWR.
Weigh your vehicle with your trailer attached, so that
you won’t go over the GVWR or GAWR. If you are using
a weight-distributing hitch, weigh the vehicle without
the spring bars in place.
You’ll get the best performance if you spread out the
weight of your load the right way, and if you choose the
correct hitch and trailer brakes.
For more information seeTowing a Trailer on page 4-55.
4-67

If No Steam Is Coming From
Your Engine
The ENGINE OVERHEATED IDLE ENGINE message,
along with a low coolant condition, can indicate a
serious problem.
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. SeeTowing a Trailer on page 4-55.
If you get the ENGINE COOLANT HOT message with
no sign of steam, try this for a minute or so:
1. Turn on your heater to full hot at the highest fan
speed and open the windows as necessary.
2. If you are in a traffic jam, shift to NEUTRAL (N);
otherwise, shift to the highest gear while
driving — DRIVE (D).
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 and you have not stopped, pull
over, stop, and park your vehicle right away.If there is still no sign of steam, 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. Also, see “Overheated Engine Protection
Operating Mode” later in this section.
You may decide not to lift the hood but to get service
help right away.
Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
ENGINE POWER IS REDUCED message is displayed,
an overheat protection mode which alternates ring
groups of cylinders helps prevent engine damage. In this
mode, you will notice a loss in power and engine
performance. This operating mode allows your vehicle
to be driven to a safe place in an emergency. Driving
extended miles (km) and/or towing a trailer in the
overheat protection mode should be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any repair.
The engine oil will be severely degraded. Repair the
cause of coolant loss, change the oil and reset the oil
life system. SeeEngine Oil on page 5-13.
5-28

5. With the coolant surge tank pressure cap off, start
the engine and let it run until you can feel the upper
radiator hose getting hot. Watch out for the engine
cooling fan.
By this time, the coolant level inside the coolant
surge tank may be lower. If the level is lower, add
more of the proper mixture to the coolant surge tank
until the level reaches the FULL COLD mark.
6. Then replace the pressure cap. Be sure the
pressure cap is hand-tight and fully seated.
7. Verify coolant level after engine is shut off and the
coolant is cold. If necessary, repeat coolant ll
procedure steps 1 through 7.
Engine Fan Noise
If your 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 fan is spinning slower and the clutch is
not fully engaged. This improves fuel economy and
reduces fan noise. Under heavy vehicle loading, trailer
towing, and/or high outside temperatures, the fan
speed increases as the clutch more fully 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 partially
disengages.
If your vehicle has electric cooling fans, you may hear
the fans spinning at low speed during most everyday
driving. The fans may turn off if no cooling is required.
Under heavy vehicle loading, trailer towing, and/or
high outside temperatures, or if you are operating your
air conditioning system, the fans may change to
high speed and you may hear an increase in fan noise.
This is normal and indicates that the cooling system
is functioning properly. The fans will change to low
speed when additional cooling is no longer required.
5-33

Spare tire carrier hinge and latch: Inspect for leaks
and lubricate if required. Remove the setscrew at the
hinge casting and add lubricant, moving the hinge back
and forth periodically, until lubricant can be seen
coming from the setscrew opening. Install setscrew and
tighten to 7 ft lb (9Y).See Recommended Fluids
and Lubricants on page 6-12 for what lubricant to use.
(g)Check vent hose at transfer case for kinks and
proper installation.
(h)Change automatic transmission fluid and filter if the
vehicle is mainly driven under one or more of these
conditions:
In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police, or delivery
service.
(i)Drain, flush, and refill cooling system. This service can
be complex; you should have your dealer/retailer perform
this service. See Engine Coolant on page 5-24 for what to
use. Inspect hoses. Clean radiator, condenser, pressure
cap, and filler neck. Pressure test the cooling system and
pressure cap.(j)A fluid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired and
the fluid level checked. Add fluid if needed.
(k)Visually inspect belt for fraying, excessive cracks, or
obvious damage. Replace belt if necessary.
Owner Checks and Services
These owner checks and services should be performed
at the intervals specied to help ensure the safety,
dependability, and emission control performance of your
vehicle. Your dealer/retailer can assist you with these
checks and services.
Be sure any necessary repairs are completed at once.
Whenever any uids or lubricants are added to your
vehicle, make sure they are the proper ones, as shown
inRecommended Fluids and Lubricants on page 6-12.
6-8

HUMMER Technician Roadside Service
(U.S. only)
HUMMER’s exceptional Roadside Service is more
than an auto club or towing service. It provides every
HUMMER owner in the United States with the advantage
of contacting a HUMMER advisor and, where available, a
HUMMER trained dealer technician who can provide
on-site service.
A dealer technician will travel to your location generally
within a 30 mile radius of a participating HUMMER
dealership. If beyond this radius, we will arrange to have
your car towed to the nearest HUMMER dealership.
Each technician travels with a specially equipped service
vehicle complete with the necessary HUMMER parts
and tools required to handle most roadside repairs.
Calling for Assistance
For prompt and efficient assistance when calling, please
provide the following to the Roadside Assistance
Representative:
Your name, home address, and home telephone
number
Telephone number of your location
Location of the vehicle
Model, year, color, and license plate number of
the vehicle
Odometer reading, Vehicle Identication
Number (VIN), and delivery date of the vehicle
Description of the problem
Towing and Road Service Exclusions
Specically excluded from Roadside Service coverage
are towing or services for vehicles operated on a
non-public roadway or highway, nes, impound towing
caused by a violation of local, Municipal, State, Provincial
or Federal law, and mounting, dismounting or changing of
snow tires, chains, or other traction devices.
Roadside Assistance is not part of or included in the
coverage provided by the New Vehicle Limited Warranty.
HUMMER and General Motors of Canada Limited
reserve the right to make any changes or discontinue
the Roadside Assistance program at any time without
notication.
Scheduling Service Appointments
When your vehicle requires warranty service, contact
your dealer/retailer and request an appointment.
By scheduling a service appointment and advising your
service consultant of your transportation needs, your
dealer/retailer can help minimize your inconvenience.
7-8

If a Crash Occurs
Here is what to do if you are involved in a crash.
Try to relax and then check to make sure you are
all right. If you are uninjured, make sure that no
one else in your vehicle, or the other vehicle,
is injured.
If there has been an injury, call emergency services
for help. Do not leave the scene of a crash until
all matters have been taken care of. Move
your vehicle only if its position puts you in danger
or you are instructed to move it by a police officer.
Give only the necessary and requested information
to police and other parties involved in the crash.
Do not discuss your personal condition, mental
frame of mind, or anything unrelated to the crash.
This will help guard against post-crash legal action.
If you need roadside assistance, call GM Roadside
Assistance. SeeRoadside Assistance Program on
page 7-6for more information.
If your vehicle cannot be driven, know where the
towing service will be taking it. Get a card from
the tow truck operator or write down the driver’s
name, the service’s name, and the phone number.
Remove any valuables from your vehicle before it is
towed away. Make sure this includes your insurance
information and registration if you keep these items
in your vehicle.
Gather the important information you will need from
the other driver. Things like name, address, phone
number, driver’s license number, vehicle license
plate, vehicle make, model and model year, Vehicle
Identication Number (VIN), insurance company and
policy number, and a general description of the
damage to the other vehicle.
If possible, call your insurance company from the
scene of the crash. They will walk you through the
information they will need. If they ask for a police
report, phone or go to the police department
headquarters the next day and you can get a copy of
the report for a nominal fee. In some states/provinces
with “no fault” insurance laws, a report may not be
necessary. This is especially true if there are no
injuries and both vehicles are driveable.
7-12

R
Radio Frequency Identication (RFID), Privacy....7-17
Radios..........................................................3-72
Radio(s)........................................................3-75
Radios
Navigation/Radio System,
see Navigation Manual............................3-104
Rear Seat Audio........................................3-114
Reception.................................................3-117
Setting the Clock.........................................3-73
Theft-Deterrent..........................................3-116
Reading Lamps..............................................3-19
Rear Air Conditioning and Heating System
and Electronic Climate Controls.....................3-29
Rear Axle......................................................5-45
Locking........................................................ 4-6
Rear Door Security Locks................................2-12
Rear Heated Seats........................................... 1-8
Rear Seat Armrest..........................................2-65
Rear Seat Audio (RSA)..................................3-114
Rear Seat Entertainment System.....................3-105
Rear Vision Camera........................................2-50
Rear Windshield Washer/Wiper.........................3-11
Rearview Mirror, Automatic Dimming with
Compass and Temperature Display................2-45
Reclining Seatbacks, Power............................... 1-5Recommended Fluids and Lubricants.................6-12
Recovery Loops..............................................4-40
Recreational Vehicle Towing.............................4-51
Remote Keyless Entry (RKE) System.................. 2-4
Remote Keyless Entry (RKE) System, Operation . . . 2-5
Remote Vehicle Start........................................ 2-8
Removing the Flat Tire and Installing
the Spare Tire.............................................5-88
Removing the Spare Tire and Tools...........5-80, 5-84
Replacement Bulbs.........................................5-53
Replacement Parts, Maintenance......................6-14
Reporting Safety Defects
Canadian Government..................................7-14
General Motors...........................................7-14
United States Government............................7-14
Restraint System Check
Checking the Restraint Systems....................1-76
Replacing Restraint System Parts
After a Crash..........................................1-77
Retained Accessory Power (RAP)......................2-29
Ride Height, Selectable Extended Rear Ride......4-53
Roadside
Assistance Program....................................... 7-6
Rocking Your Vehicle to Get it Out....................4-40
Routing, Engine Drive Belt...............................6-15
Running the Engine While Parked.....................2-44
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