ECU HUMMER H2 2005 Service Manual

{CAUTION:
If the airbag readiness light ever comes on
when you have turned off the airbag, it means
that something may be wrong with the airbag
system. The right front passenger’s airbag
could inate even though the switch is off. If
this ever happens, do not let anyone whom the
national government has identied as a
member of a passenger airbag risk group sit in
the right front passenger’s position (for
example, do not secure a rear-facing child
restraint in the right front passenger’s seat)
until you have your vehicle serviced. See
Airbag Off Switch on page 1-65, for more on
this, including important safety information.
Charging System Light
The charging system light
will come on briey when
you turn on the ignition,
but the engine is not
running, as a check to
show you it is working.
It should go out once the engine is running. If it stays
on, or comes on while you are driving, you may have a
problem with the charging system. It could indicate
that you have problems with a generator drive belt, or
another electrical problem. Have it checked right
away. Driving while this light is on could drain your
battery.
When this light comes on the DIC will also display the
battery not charging message. SeeDIC Warnings
and Messages on page 3-47.
If you must drive a short distance with the light on, be
certain to turn off all your accessories, such as the radio
and air conditioner.
3-31

Security Light
This light will come on
briey when you turn the
key toward START.
The light will stay on until
the engine starts.
If the light ashes, the Passlock
®system has entered a
tamper mode. If the vehicle fails to start, seePasslock®
on page 2-24.
If the light comes on continuously while driving and
stays on, there may be a problem with the Passlock
®
system. Your vehicle will not be protected by Passlock®,
and you should see your dealer.
Also, seeContent Theft-Deterrent on page 2-22for
additional information regarding the security light.
Cruise Control Light
The cruise light comes on
whenever you set your
cruise control. See “Cruise
Control” underTurn
Signal/Multifunction Lever
on page 3-7.
Highbeam On Light
This light will illuminate
when the headlamp high
beams are in use.
SeeHeadlamp High/Low-Beam Changer on page 3-8.
3-41

XM™ Radio Messages (cont’d)
Radio Display
MessageCondition Action Required
No Info Category Name not
availableNo category information is available at this time on this
channel. The system is working properly.
No Info No Text/Informational
message availableNo text or informational messages are available at this
time on this channel. The system is working properly.
Not Found No channel available for
the chosen categoryThere are no channels available for the selected category.
The system is working properly.
XM Locked Theft lock active The XM receiver in the vehicle may have previously been
in another vehicle. For security purposes, XM receivers
cannot be swapped between vehicles. If this message is
received after having your vehicle serviced, check with
your GM dealer.
Radio ID Radio ID label
(channel 0)If tuned to channel 0, this message will alternate with the
XM Radio 8 digit radio ID label. This label is needed to
activate the service.
Unknown Radio ID not known
(should only be if
hardware failure)If this message is received when tuned to channel 0, there
may be a receiver fault. Consult with your GM dealer.
Chk XMRcvr Hardware failure If this message does not clear within a short period of time,
the receiver may have a fault. Consult with your GM
dealer.
3-68

XM™ Radio Messages (cont’d)
Radio Display
MessageCondition Action Required
No Info Category Name not
availableNo category information is available at this time on this
channel. The system is working properly.
No Info No Text/Informational
message availableNo text or informational messages are available at this
time on this channel. The system is working properly.
Not Found No channel available for
the chosen categoryThere are no channels available for the selected category.
The system is working properly.
XM Locked Theft lock active The XM receiver in the vehicle may have previously been
in another vehicle. For security purposes, XM receivers
cannot be swapped between vehicles. If this message is
received after having your vehicle serviced, check with
your GM dealer.
Radio ID Radio ID label
(channel 0)If tuned to channel 0, this message will alternate with the
XM Radio 8 digit radio ID label. This label is needed to
activate the service.
Unknown Radio ID not known
(should only be if
hardware failure)If this message is received when tuned to channel 0, there
may be a receiver fault. Consult with your GM dealer.
Chk XMRcvr Hardware failure If this message does not clear within a short period of time,
your receiver may have a fault. Consult with your GM
dealer.
3-81

Off-Road Driving
This off-road guide is meant to provide advice for when
you drive your vehicle off paved roads. Also, see
Braking on page 4-6.
Off-road driving can be great fun. But it does have
some denite hazards. The greatest of these is
the terrain itself.
“Off-roading” means you have left the great North
American road system behind. Traffic lanes are not
marked. Curves are not banked. There are no
road signs. Surfaces can be slippery, rough, uphill or
downhill. In short, you have gone right back to nature.
Off-road driving involves some new skills. And that is
why it is very important that you read this guide. You will
nd many driving tips and suggestions. These will help
make your off-road driving safer and more enjoyable.
Before You Go Off-Roading
There are some things to do before you go out. For
example, be sure to have all necessary maintenance
and service work done. Check to make sure all
underbody shields are properly attached. Make sure any
equipment you may need (rst aid kit, cell phone,
ashlight, etc.) is securely stored in the vehicle.Be sure you read all the information about your
four-wheel-drive vehicle in this manual. Is there enough
fuel? Is the spare tire fully inated? Are the uid
levels up where they should be? What are the local
laws that apply to off-roading where you will be driving?
If you do not know, you should check with law
enforcement people in the area. Will you be on
someone’s private land? If so, be sure to get the
necessary permission.
Removable Side Steps
Your vehicle may be equipped with removable
side steps.
Remove the steps prior to off roading to give your
vehicle more ground clearance and to prevent damage
to the vehicle from the side steps dragging and/or
catching on obstacles.
Notice:Do not drive off road with the side steps
attached to your vehicle. You can damage the side
steps and/or your vehicle’s frame if they get caught
or drag against an obstacle. This damage would not
be covered by your vehicle’s warranty. Always
remove the side steps prior to any off road driving.
4-16

4. Thread the knob through the remaining hole — rst
into the rocker panel protector and then into the
threaded hole in the side step bracket.
Notice:Threading the knob into the side step and
then into the rocker panel will not secure the step.
The step could fall off the vehicle and be damaged.
Always thread the knob through the rocker panel
rst. After the knob is installed, try moving the step
left and right to be sure the step is secure.5. Hand-tighten the knob by turning it clockwise until it
is seated against the rocker panel protector bracket
and then tighten it to 10 lb ft (13.5Y) with the
tool as shown.
4-18

To install a step:
1. Before installing the bolts:
Remove all traces of the original adhesive patch.
Clean the threads of the bolts with denatured
alcohol or equivalent and allow threads to dry.
Apply Threadlocker (GM Part No. 12345382, in
Canada 10953489) or equivalent.
2. Install the side step to the vehicle. You may need
someone to assist you in the installation.
3. Install the nuts and bolts for the two inner brackets
rst, but do not tighten them.
4. Using a level, make sure the step is level in
relationship to the vehicle. Then, tighten the
inner bracket nuts and bolts.
5. Install the other nuts and bolts. Tighten all nuts and
bolts to 39 lb ft (50Y).
Loading Your Vehicle for
Off-Road Driving
There are some important things to remember about
how to load your vehicle.
The heaviest things should be on the load oor and
forward of your rear axle. Put heavier items in the
rear area, as far forward as you can.
Be sure the load is secured properly, so driving on
the off-road terrain does not toss things around.
4-20

{CAUTION:
Cargo on the load oor piled higher than
the seatbacks can be thrown forward
during a sudden stop. You or your
passengers could be injured. Keep cargo
below the top of the seatbacks.
Unsecured cargo on the load oor can be
tossed about when driving over rough
terrain. You or your passengers can be
struck by ying objects. Secure the
cargo properly.
Heavy loads on the roof raise the vehicle’s
center of gravity, making it more likely to
roll over. You can be seriously or fatally
injured if the vehicle rolls over. Put heavy
loads inside the cargo area, not on the
roof. Keep cargo in the cargo area as far
forward and low as possible.
You will nd other important information in this manual.
SeeLoading Your Vehicle on page 4-58andTires
on page 5-54.
Environmental Concerns
Off-road driving can provide wholesome and satisfying
recreation. However, it also raises environmental
concerns. We recognize these concerns and urge every
off-roader to follow these basic rules for protecting
the environment:
Always use established trails, roads and areas that
have been specially set aside for public off-road
recreational driving; obey all posted regulations.
Avoid any driving practice that could damage
the environment — shrubs, owers, trees,
grasses — or disturb wildlife (this includes
wheel-spinning, breaking down trees or
unnecessary driving through streams or over
soft ground).
Always carry a litter bag — make sure all refuse is
removed from any campsite before leaving.
Take extreme care with open res (where
permitted), camp stoves and lanterns.
Never park your vehicle over dry grass or other
combustible materials that could catch re from
the heat of the vehicle’s exhaust system.
4-21

Include an ice scraper, a small brush or broom, a
supply of windshield washer uid, a rag, some winter
outer clothing, a small shovel, a ashlight, a red
cloth, and a couple of reective warning triangles. And,
if you will be driving under severe conditions, include
a small bag of sand, a piece of old carpet or a couple of
burlap bags to help provide traction. Be sure you
properly secure these items in your vehicle.
Driving on Snow or Ice
Most of the time, those places where your tires meet
the road probably have good traction.
However, if there is snow or ice between your tires and
the road, you can have a very slippery situation. You
will have a lot less traction, or grip, and will need to be
very careful.
What is the worst time for this? Wet ice. Very cold snow
or ice can be slick and hard to drive on. But wet ice
can be even more trouble because it may offer the least
traction of all. You can get wet ice when it is about
freezing (32°F; 0°C) and freezing rain begins to fall. Try
to avoid driving on wet ice until salt and sand crews
can get there.
Whatever the condition — smooth ice, packed, blowing,
or loose snow — drive with caution.
4-49

If you put things inside your vehicle – like suitcases,
tools, packages, or anything else – they go as fast as
the vehicle goes. If you have to stop or turn quickly,
or if there is a crash, they’ll keep going.
{CAUTION:
Things you put inside your vehicle can strike
and injure people in a sudden stop or turn, or
in a crash.
Put things in the cargo area of your
vehicle. Try to spread the weight evenly.
Never stack heavier things, like suitcases,
inside the vehicle so that some of them
are above the tops of the seats.
Do not leave an unsecured child restraint
in your vehicle.
When you carry something inside the
vehicle, secure it whenever you can.
Do not leave a seat folded down unless
you need to.
There’s also important loading information for off-road
driving in this manual. See “Loading Your Vehicle
for Off-Road Driving” underOff-Road Driving on
page 4-16.
Add-On Equipment
When you carry removable items, you may need to put
a limit on how many people you can carry inside
your vehicle. Be sure to weigh your vehicle before you
buy and install the new equipment.
Notice:Overloading your vehicle may cause
damage. Repairs would not be covered by your
warranty. Do not overload your vehicle.
Remember not to exceed the Gross Axle Weight Rating
(GAWR) of the front or rear axle.
The Cargo Weight Rating (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
vehicle’s CWR.
4-63