2006 HUMMER H2 engine

Notice:Using a tool to force the key from the
ignition switch could cause damage or break the
key. Use the correct key and turn the key only with
your hand. Make sure the key is all the way in. If
it is, turn the steering wheel left and right while you
turn the key hard. If none of this works, then
your vehicle needs service.
B (ACCESSORY):This position lets you use things like
the radio and the windshield wipers when the engine
is off.
Notice:Lengthy operation of features such as the
radio in the accessory ignition position may drain the
battery and prevent your vehicle from starting. Do not
operate your vehicle in the accessory ignition
position for a long period of time.
C (RUN):This is the position for driving.
D (START):This position starts the engine.
Retained Accessory Power (RAP)
The Retained Accessory Power (RAP) feature will allow
certain features on your vehicle to continue to work
for up to 10 minutes after the ignition key is turned to
LOCK or until one of the doors is opened.
Starting the Engine
Your vehicle is equipped with Starter Motor Control.
This feature assists in starting the engine and protects
the electrical system. This feature may cause the
engine to crank even after the ignition key is not
in START.
Move your shift lever to PARK (P) or NEUTRAL (N).
Your engine will not start in any other position — that is
a safety feature. To restart when you are already
moving, use NEUTRAL (N) only.
Notice:Do not try to shift to PARK (P) if your
vehicle is moving. If you do, you could damage the
transmission. Shift to PARK (P) only when your
vehicle is stopped.
1. With your foot off the accelerator pedal, turn the
ignition key to START. When the engine starts,
let go of the key. The idle speed will go down as
your engine gets warm.
Notice:Holding your key in START for longer than
15 seconds at a time will disengage the starter
motor, cause your battery to be drained much
sooner, and add excessive heat that can damage
your starter motor. Try not to hold the key in
START for longer than 15 seconds and wait about
15 seconds between each try to help avoid draining
your battery or damaging your starter.
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2. If it does not start within 10 seconds, push the
accelerator pedal all the way to the oor, while
you hold the ignition key in START. When the
engine starts, let go of the key and let up on the
accelerator pedal. Wait about 15 seconds between
each try.
When starting your engine in very cold weather (below
0°F or−18°C), do this:
1. With your foot off the accelerator pedal, turn the
ignition key to START and hold it there up to
15 seconds. When the engine starts, let go of
the key.
2. If your engine still will not start, or starts but then
stops, it could be ooded with too much gasoline.
Try pushing your accelerator pedal all the way to the
oor and holding it there as you hold the key in
START for about three seconds. When the engine
starts, let go of the key and accelerator. If the
vehicle starts briey but then stops again, do the
same thing, but this time keep the pedal down
for ve or six seconds. This clears the extra
gasoline from the engine.
Notice:Your engine is designed to work with the
electronics in your vehicle. If you add electrical
parts or accessories, you could change the way the
engine operates. Before adding electrical equipment,
check with your dealer. If you do not, your engine
might not perform properly. Any resulting damage
would not be covered by your vehicle’s warranty.Engine Coolant Heater
Your vehicle may be equipped with an engine
coolant heater.
In very cold weather, 0°F (−18°C) or colder, the engine
coolant heater can help. You will get easier starting
and better fuel economy during engine warm-up.
Usually, the coolant heater should be plugged in a
minimum of four hours prior to starting your vehicle. At
temperatures above 32°F (0°C), use of the coolant
heater is not required. Your vehicle may also have an
internal thermostat in the plug end of the cord. This will
prevent operation of the engine coolant heater when
the temperature is at or above 0°F (-18°C) as noted
on the cord.
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Locate the electrical cord near the front recovery
loop on the driver’s side of the vehicle.
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3. Plug it into a normal, grounded 110-volt AC outlet.
{CAUTION:
Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the
wrong kind of extension cord could overheat
and cause a re. You could be seriously
injured. Plug the cord into a properly grounded
three-prong 110-volt AC outlet. If the cord will
not reach, use a heavy-duty three-prong
extension cord rated for at least 15 amps.
4. Before starting the engine, be sure to unplug and
store the cord as it was before to keep it away
from moving engine parts. If you do not, it could be
damaged.
How long should you keep the coolant heater plugged in?
The answer depends on the outside temperature, the
kind of oil you have, and some other things. Instead of
trying to list everything here, we ask that you contact
your dealer in the area where you will be parking your
vehicle. The dealer can give you the best advice for that
particular area.
Automatic Transmission Operation
Your vehicle is equipped with an automatic transmission
and features an electronic shift position indicator
located within the instrument panel cluster.
There are several different positions for your shift lever.
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PARK (P):This position locks your drive wheels. It is
the best position to use when you start your engine
because your vehicle cannot move easily.
{CAUTION:
It is dangerous to get out of your vehicle if the
shift lever is not fully in PARK (P) with the
parking brake rmly set. Your vehicle can roll.
Do not leave your vehicle when the engine is
running unless you have to. If you have left the
engine running, the vehicle can move
suddenly. You or others could be injured. To
be sure your vehicle will not move, even when
you are on fairly level ground, always set your
parking brake and move the shift lever to
PARK (P). SeeShifting Into Park (P) on
page 2-35. If you are pulling a trailer, see
Towing a Trailer on page 4-63.
{CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the
transmission is in PARK (P). You or someone
else could be seriously injured. Be sure to set
the parking brake before placing the transfer
case in NEUTRAL. SeeParking Brake on
page 2-34.
REVERSE (R):Use this gear to back up.
Notice:Shifting to REVERSE (R) while your vehicle
is moving forward could damage the transmission.
The repairs would not be covered by your warranty.
Shift to REVERSE (R) only after your vehicle is
stopped.
To rock your vehicle back and forth to get out of snow,
ice or sand without damaging your transmission,
seeIf Your Vehicle is Stuck in Sand, Mud, Ice or Snow
on page 4-50.
NEUTRAL (N):In this position, your engine does not
connect with the drive wheels. To restart when you
are already moving, use NEUTRAL (N) only.
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{CAUTION:
Shifting into a drive gear while your engine is
running at high speed is dangerous. Unless
your foot is rmly on the brake pedal, your
vehicle could move very rapidly. You could
lose control and hit people or objects. Do not
shift into a drive gear while your engine is
running at high speed.
Notice:Shifting out of PARK (P) or NEUTRAL (N)
with the engine running at high speed may damage
the transmission. The repairs would not be
covered by your warranty. Be sure the engine is not
running at high speed when shifting your vehicle.
DRIVE (D):This position is for normal driving. If
you need more power for passing, and you are:
Going less than about 35 mph (55 km/h), push your
accelerator pedal about halfway down.
Going about 35 mph (55 km/h) or more, push the
accelerator all the way down.
You will shift down to the next gear and have
more power.DRIVE (D) can be used when towing a trailer, carrying a
heavy load, driving on steep hills or for off-road
driving. You may want to shift the transmission to
THIRD (3) or, if necessary, a lower gear selection if the
transmission shifts too often.
THIRD (3):This position is also used for normal driving,
however it offers more power and lower fuel economy
than DRIVE (D).
SECOND (2):This position gives you more power but
lower fuel economy. You can use SECOND (2) on
hills. It can help control your speed as you go down
steep mountain roads, but then you would also want to
use your brakes off and on.
If you manually select SECOND (2), the transmission
will drive in second gear. You may use this feature
for reducing the speed of the rear wheels when you are
trying to start your vehicle from a stop on slippery
road surfaces. Once the vehicle is moving, shift into
DRIVE (D).
FIRST (1):This position gives you even more power,
but lower fuel economy than SECOND (2). You can use
it on very steep hills, or in deep snow or mud. If the
shift lever is put in FIRST (1) while the vehicle is moving
forward, the transmission will not shift into rst gear
until the vehicle is going slowly enough.
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Notice:Spinning the tires or holding the vehicle in
one place on a hill using only the accelerator
pedal may damage the transmission. If you are
stuck, do not spin the tires. When stopping on a hill,
use the brakes to hold the vehicle in place.
On cold days, approximately 32°F (0°C) or colder, your
transmission is designed to shift differently until the
engine reaches normal operating temperature. This is
intended to improve heater performance.
Tow/Haul Mode
Your vehicle is equipped
with a tow/haul mode.
The button is located
on the instrument panel
to the right of the
steering wheel.
You can use this feature to assist when towing or
hauling a heavy load. See “Tow/Haul Mode” under
Towing a Trailer on page 4-63for more information.
Full-Time Four-Wheel Drive
The transfer case on your Full-Time Four-Wheel Drive
vehicle is designed to constantly send your engine’s
driving power to all four wheels for extra traction. To get
the most out of Full-Time Four-Wheel Drive, you
must be familiar with its operation.
Notice:Driving on pavement in Four-Wheel
High Lock or Four Wheel Low Lock for extended
periods may cause premature wear on your vehicle’s
powertrain and tires. Do not drive in Four-Wheel
High Lock or Four-Wheel Low Lock on pavement for
extended periods.
Transfer Case Buttons
The transfer case buttons
are located to the right of
the instrument panel
cluster. Use these switches
to shift into and out of
the different Full-Time
Four-Wheel Drive modes.
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Indicator lights in the buttons show which mode you are
in. The indicator lights will come on briey when you
turn on the ignition and one will stay on. If the lights do
not come on, you should take your vehicle to your
dealer for service. An indicator light will ash while
shifting the transfer case. It will remain on when the shift
is complete. If for some reason the transfer case
cannot make a requested shift, it will return to the last
chosen setting.
If the SERVICE 4WD message stays on, you should
take your vehicle to your dealer for service. See “Service
4WD message” underDriver Information Center (DIC)
on page 3-45.
Shifting between Four-Wheel High and
Four-Wheel-High Lock
With the vehicle traveling less than 40 mph (64 km/h),
press and release the Four-Wheel High or
Four-Wheel-Low Lock button. The indicator light will
ash while shifting. It will remain on when the shift
is complete.
It may be necessary to drive backwards for a short
distance of 25 feet (7.5 m) to get the lock feature
to disengage.
Shifting into Four-Wheel-Low Lock
To shift into Four-Wheel-Low Lock, the ignition must be in
RUN and the vehicle must be stopped or moving less
than 3 mph (5 km/h) with the transmission in
NEUTRAL (N). The preferred method for shifting into
Four-Wheel Low is to have your vehicle moving
1 to 2 mph (1.6 to 3.2 km/h). Press and release the
Four-Wheel-Low Lock button. You must wait for the
Four-Wheel-Low Lock indicator light to stop ashing and
remain lit before shifting your transmission in gear.
Notice:Shifting the transmission into gear before
the indicator light stops ashing could cause
damage to the transfer case. Always wait until the
indicator light stops ashing before putting the
transmission back in gear.
It is normal for your vehicle to have engagement noise
and bump when shifting between Four-Wheel Low
and Four-Wheel High or Four-Wheel-High Lock ranges
or from NEUTRAL with the engine running.
If the Four-Wheel-Low Lock button is pressed when
your vehicle is in gear and/or moving, the Four-Wheel
Low Lock indicator light will ash for 15 seconds and not
complete the shift unless your vehicle is moving less
than 3 mph (5 km/h) and the transmission is in
NEUTRAL (N). After 15 seconds the transfer case will
return to the setting last chosen.
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Shifting Out of Four-Wheel Low Lock
To shift from Four-Wheel-Low Lock to Four-Wheel High
or Four-Wheel-High Lock, your vehicle must be stopped
or moving less than 3 mph (5 km/h) with the transmission
in NEUTRAL (N) and the ignition in RUN. The preferred
method for shifting out of Four-Wheel-Low Lock is to
have your vehicle moving 1 to 2 mph (1.6 to 3.2 km/h).
Press and release the Four-Wheel High or
Four-Wheel-High Lock button. You must wait for the
Four-Wheel High or Four-Wheel-High Lock indicator light
to stop ashing and remain lit before shifting your
transmission into gear.
It is normal for your vehicle to have engagement noise
and bump when shifting between Four-Wheel Low
and Four-Wheel High or Four-Wheel-High Lock ranges
or from NEUTRAL with the engine running.
If the Four-Wheel High or Four-Wheel-High Lock button
is pressed when your vehicle is in gear and/or moving,
the Four-Wheel High or Four-Wheel-High Lock indicator
light will ash for 30 seconds but will not complete
the shift unless your vehicle is moving less than 3 mph
(5 km/h) and the transmission is in NEUTRAL (N).
Notice:Shifting the transmission into gear before
the indicator light stops ashing could cause
damage to the transfer case. Always wait until the
indicator light stops ashing before putting the
transmission back in gear.
Shifting into NEUTRAL
To shift the transfer case to NEUTRAL, do the following:
1. Make sure the vehicle is parked so that it will
not roll.
2. Set the parking brake.
3. Start the vehicle or turn the ignition to RUN.
4. Put the transmission in NEUTRAL (N).
5. Shift the transfer case to Four-Wheel High.
6. Simultaneously press and hold the Four-Wheel
High and Four-Wheel Low Lock buttons for
10 seconds. The NEUTRAL light will come on when
the transfer case shift to NEUTRAL is complete.
7. If the engine is running, verify that the transfer case
is in NEUTRAL by shifting the transmission to
REVERSE (R), then shift the transmission to
DRIVE (D) and then back to NEUTRAL (N).
8. Turn the ignition to ACCESSORY, which will turn
the engine off.
9. Place the transmission shift lever in PARK (P).
10. Turn the ignition to LOCK.
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