AUX HUMMER H3 2008 Owners Manual

If you start your vehicle in a dark garage, the automatic
headlamp system will come on immediately. Once
you leave the garage, it will take about one minute for
the automatic headlamp system to change to DRL if it is
light outside. During that delay, the instrument panel
cluster may not be as bright as usual. Make sure
the instrument panel brightness control is in the full
bright position. SeeInstrument Panel Brightness
on page 3-19.
Off-Road Lamps
The off-road lamps, if the vehicle has them, provide
auxiliary lighting when the vehicle is used off road.
These lamps are not intended to be used in place of
existing vehicle lighting. The lamps are not to be used
on any public street or highway and are to be covered
when not in use. Check your state and local laws before
installing or using any auxiliary lighting. In some
states it may be necessary to remove the roof lamps
when operating the vehicle on the highway.The switches for the off-road lamps are located in the
center of the instrument panel below the climate
controls. One switch is used for the front lower-grille
mounted off-road lamps, if the vehicle has them, and the
other switch is used for the roof-mounted off-road
lamps, if the vehicle has them.
To use the lamps, remove the covers from the lamps and
press the switch to turn them on or off. An indicator light
on the switch will turn on when the lamps are on.
Notice:Turning on the off-road lamps before
removing the lamp covers could damage the
off-road lamps and the covers. Always remove the
covers before turning on the off-road lamps.
The off-road lamps remain on even after the ignition is
turned off. The off-road lamp switch must be pressed
to turn them off.Roof Mounted Off-Road
Light Switch
Lower Grille Off-Road
Light Switch
3-18

Accessory Power Outlet(s)
Your vehicle has accessory power outlets.
With accessory power outlets you can plug in auxiliary
electrical equipment such as a cellular telephone or
CB radio.
Your vehicle has two accessory power outlets located on
the lower part of the instrument panel below the climate
control system and there may be one located in the rear
cargo area. A small cap must be pulled down to access
an accessory power outlet. When not using an outlet, be
sure to cover it with the protective cap.
Notice:Leaving electrical equipment on for
extended periods will drain the battery. Always
unplug electrical equipment when not in use and do
not plug in equipment that exceeds the maximum
amperage rating of 20 amperes.Certain electrical accessories may not be compatible
with the accessory power outlet and could result
in blown vehicle or adapter fuses. If you experience a
problem, see your dealer for additional information
on accessory power outlets.
Notice:Adding any electrical equipment to your
vehicle may damage it or keep other components
from working as they should. The repairs would not
be covered by your warranty. Do not use equipment
exceeding maximum amperage rating of 20 amperes.
Check with your dealer/retailer before adding
electrical equipment.
When adding electrical equipment, be sure to follow the
proper installation instructions included with the
equipment.
Notice:Improper use of the power outlet can cause
damage not covered by your warranty. Do not
hang any type of accessory or accessory bracket
from the plug because the power outlets are
designed for accessory power plugs only.
3-21

Trailer Brake Control Wiring Harness
The trailer brake control wiring harness is located
under the instrument panel to the right of the steering
column. The wires are taped to the harness that goes
to the courtesy light under the instrument panel.
The harness will contain the following wires:
Red Wire: AUX B+
Black Wire: Ground
Light Blue Wire: Brake Signal
Dark Blue Wire: Trailer Brakes
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 4-50.
4-62

Fuse Usage
7 Regulated Voltage Control Power
8 Power Locks
9 Sunroof, Front Washer Pump
10 Accessories (SPO)
11 Air Compressor
12 Transfer Case Control Module
13Radio, Heating, Ventilation, Air
Conditioning Display
14 Body Control Module
15 Rear Wiper Motor
16 Rear Wiper Pump Switch
17 Air Injection Reactor (AIR) Solenoid
18 Spare 6
19 Cluster
20 Rear Turn Signal, Hazard Signal
21 Powertrain Control Module 1
22Mass Air Flow Sensor, Purge
Solenoid
23 Injector
24 Fog Lamp
25 Powertrain Control Module B
26 Transmission Control Module (TCM)
27 Airbags
28 Back-up LampsFuse Usage
29 Antilock Brakes, StabiliTrak®
30 Rear Window Defogger
31 Canister Vent
32 Regulated Voltage Control VSense+
33 Ignition 1
34 Transmission
35 Cruise, Inside Rearview Mirror
36 Horn
37 Driver Side Rear Park Lamp
38 Amplier
39Reduced Intensity Low-Beam
Daytime Running Lamps
40 Passenger Side Headlamp
41 Driver Side Headlamp
42 Trailer Back-Up Lamp
43 Front Park Lamps
44 Air Injection Reactor (AIR) Solenoid
45 Auxiliary Power 2
46 Electronic Throttle Control
47 Oxygen Sensor
48 Air Conditioning Clutch
49 Passenger Side Rear Park Lamp
50 Spare
51 Auxiliary Power 1
5-105