2008 HUMMER H2 ignition

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 (ACC/ACCESSORY):This position lets things like
the radio and the windshield wipers operate while
the engine is off.
Lengthy operation of features such as the radio in the
ACC/ACCESSORY ignition position and the ON/RUN
position may drain the battery and prevent your vehicle
from starting. Do not operate your vehicle in the
ACC/ACCESSORY ignition position for a long period
of time.
C (ON/RUN):This is the position for driving. It is the
position the ignition switch returns to after the engine
starts, and the key is released.
The battery could be drained if you leave the key in
the ACC/ACCESSORY or ON/RUN position with
the engine off. You may not be able to start your
vehicle if the battery is allowed to drain for an extended
period of time.
D (START):This position starts the engine.Key In the Ignition
Never leave your vehicle with the keys inside, as it is an
easy target for joy riders or thieves. If you leave the
key in the ignition and park your vehicle, a chime
will sound, when you open the driver’s door. Always
remember to remove your key from the ignition and take
it with you. This will lock your ignition and transmission.
Also, always remember to lock the doors.
The battery could be drained if you leave the key in the
ignition while your vehicle is parked. You may not be
able to start your vehicle after it has been parked for an
extended period of time.
Retained Accessory Power (RAP)
These vehicle accessories can be used for up to
10 minutes after the engine is turned off:
Audio System
Sunroof
Power Windows
The sunroof and power windows will continue to work
up to 10 minutes after the key is turned to LOCK/OFF or
until any door is opened. The radio will continue to
work for up to 10 minutes after the key is turned
to LOCK/OFF or until the driver’s door is opened.
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Starting the Engine
Move your shift lever to PARK (P) or NEUTRAL (N).
Your engine will not start in any other position – this 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.
Starting Procedure
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. Do not race the engine
immediately after starting it. Operate the engine and
transmission gently to allow the oil to warm up and
lubricate all moving parts.
Your vehicle has a Computer-Controlled Cranking
System. This feature assists in starting the engine
and protects components. If the ignition key is turned
to the START position, and then released when the
engine begins cranking, the engine will continue
cranking for a few seconds or until the vehicle starts.
If the engine does not start and the key is held in
START for many seconds, cranking will be stopped
after 15 seconds to prevent cranking motor damage.To prevent gear damage, this system also prevents
cranking if the engine is already running. Engine
cranking can be stopped by turning the ignition
switch to the ACC/ACCESSORY or LOCK/OFF
position.
Notice:Cranking the engine for long periods of
time, by returning the key to the START position
immediately after cranking has ended, can overheat
and damage the cranking motor, and drain the
battery. Wait at least 15 seconds between each try,
to let the cranking motor cool down.
2. If the engine does not start after 5-10 seconds,
especially in very cold weather (below 0°F or−18°C),
it could be ooded with too much gasoline. Try
pushing the accelerator pedal all the way to the oor
and holding it there as you hold the key in START
for up to a maximum of 15 seconds. Wait at least
15 seconds between each try, to allow the cranking
motor to cool down. When the engine starts, let go of
the key and accelerator. If the vehicle starts briey
but then stops again, do the same thing. This clears
the extra gasoline from the engine. Do not race the
engine immediately after starting it. Operate the
engine and transmission gently until the oil warms up
and lubricates all moving parts.
2-30

Automatic Transmission Operation
Your vehicle has a Hydra-Matic®6L80 automatic
transmission, and has an electronic shift position
indicator within the instrument panel cluster. This display
comes on when the ignition key is turned to the
ON/RUN position.
There are several different positions for the shift lever.
PARK (P):This position locks the rear wheels. It is the
best position to use when you start your engine
because your vehicle cannot move easily.
When parked on a hill, especially when the vehicle
has a heavy load, you may notice an increase in the
effort to shift out of PARK (P). See Torque Lock
(Automatic Transmission) underShifting Into PARK (P)
on page 2-41for more information.{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 2-41. If you are pulling a trailer, see
Towing a Trailer on page 4-55.
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.
2-32

When in this mode you can also choose to lock the rear
axle for additional traction in extreme off-road situations.
SeeLocking Rear Axle on page 4-6.
Notice:Operating your vehicle in
Four-Wheel-Low Lock above 50 mph (80 km/h) for
any extended period of time could cause damage to
the transfer case. Do not operate your vehicle in
Four-Wheel-Low Lock above 50 mph (80 km/h)
for extended periods.
{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 2-40.N (NEUTRAL):Shift the vehicle’s transfer case to
NEUTRAL only when towing your vehicle. See
Recreational Vehicle Towing on page 4-51orTowing
Your Vehicle on page 4-51for more information.
Indicator lights in the dial shows 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, take your vehicle to your dealer/retailer
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/retailer for service.
See “Service 4WD message” underDriver Information
Center (DIC) on page 3-49.
2-37

Shifting between Four-Wheel High and
Four-Wheel-High Lock
With the vehicle traveling less than 40 mph
(64 km/h), turn the dial to the Four-Wheel High or
Four-Wheel-High Lock position. The indicator light on
the dial 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). Turn the dial to the
Four-Wheel-Low Lock position. You must wait for the
Four-Wheel-Low Lock indicator light on the dial to
stop ashing and remain lit before shifting the
transmission in gear.When the transfer case is shifted into Four-Wheel-Low
Lock position a StabiliTrak
®indicator light will come
on to show that the system has been turned off and a
message will show in the DIC. SeeDIC Warnings
and Messages on page 3-56for more information.
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 position is selected 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.
2-38

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). Turn the dial to the
Four-Wheel High or Four-Wheel-High Lock position.
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 position
is selected 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 and apply the regular brake
pedal. SeeParking Brake on page 2-40
3. Start the vehicle or turn the ignition to ON/RUN.
4. Put the transmission in NEUTRAL (N).
5. Shift the transfer case to Two-Wheel Drive High.
6. Turn the transfer case dial clockwise to NEUTRAL
position. The transfer case will not shift to NEUTRAL
unless this position is held for 10 seconds.
The NEUTRAL light will come on and then the dial
can be slowly released. The dial will be in the
Four-Wheel Low Lock position but the transfer case
will be in NEUTRAL with the NEUTRAL light on.
7. If the engine is running, make sure that the transfer
case is in NEUTRAL (N) by shifting the transmission
to REVERSE (R) for one second, then shift the
transmission to DRIVE (D) for one second.
8. Turn the ignition to ACC/ACCESSORY, which will
turn the engine off.
9. Place the transmission shift lever in PARK (P).
10. Release the parking brake prior to moving
the vehicle.
11. Turn the ignition to LOCK/OFF.
2-39

Shifting Out of NEUTRAL
To shift out of NEUTRAL do the following:
1. Set the parking brake and apply the regular brake
pedal.
2. Shift the transmission to NEUTRAL (N) and turn
the ignition to RUN with the engine off.
3. Turn the transfer case dial to Four-Wheel High,
Four-Wheel High Lock or Four-Wheel Low Lock.
After the transfer case has shifted out of NEUTRAL
the NEUTRAL light will go out.
4. Release the parking brake prior to moving the
vehicle.
Notice:Shifting the transmission into gear before
the requested mode indicator light has stopped
ashing could damage the transfer case. To help
avoid damaging your vehicle, always wait for the
mode indicator lights to stop ashing before shifting
the transmission into gear.
5. Start the engine and shift the transmission to the
desired position.
Parking Brake
To set the parking brake, hold the regular brake pedal
down with your right foot. Push down the parking
brake pedal with your left foot.
A chime will activate and
the warning light will ash
when the parking brake
is applied and the vehicle
is moving at least 3 mph
(5 km/h) for at least
three seconds.
To release the parking brake, hold the regular brake
pedal down. Pull the bottom edge of the lever, located
above the parking brake pedal, with the parking
brake symbol, to release the parking brake.
If the ignition is on when the parking brake is released,
the brake system warning light will go off.
Notice:Driving with the parking brake on can
overheat the brake system and cause premature
wear or damage to brake system parts. Make sure
that the parking brake is fully released and the brake
warning light is off before driving.
If you are towing a trailer and are parking on any hill,
seeTowing a Trailer on page 4-55.
2-40

Shifting Into PARK (P)
{CAUTION:
It can be 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.
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, use
the steps that follow. If you are pulling a trailer,
seeTowing a Trailer on page 4-55.
1. Hold the brake pedal down with your foot and set
the parking brake. SeeParking Brake on page 2-40
for more information.
2. Move the shift lever into PARK (P) by pressing the
button on the shift lever and pushing the lever all
the way toward the front of the vehicle.
3. Turn the ignition key to LOCK/OFF.
4. Remove the key and take it with you. If you can
leave your vehicle with the key, your vehicle is
in PARK (P).
Leaving Your Vehicle With the
Engine Running
{CAUTION:
It can be dangerous to leave your vehicle with
the engine running. Your vehicle could move
suddenly if the shift lever is not fully in
PARK (P) with the parking brake rmly set.
And, if you leave the vehicle with the engine
running, it could overheat and even catch re.
You or others could be injured. Do not leave
your vehicle with the engine running.
If you have to leave your vehicle with the engine
running, be sure your vehicle is in PARK (P) and your
parking brake is rmly set before you leave it. After you
have moved the shift lever into PARK (P), hold the
regular brake pedal down. Then, see if you can move
the shift lever away from PARK (P) without rst pressing
the button on the console shift lever. If you can, it
means that the shift lever was not fully locked into
PARK (P).
2-41