engine HUMMER H2 2009 User Guide

Ignition Positions
The ignition switch has
four different positions.
To shift out of P (Park), the ignition must be in ON/RUN
or ACC/ACCESSORY and the regular brake pedal
must be applied.A (LOCK/OFF):This position locks the ignition. It also
locks the transmission on automatic transmission
vehicles. The key can be removed in LOCK/OFF.
On vehicles with an automatic transmission, the shift
lever must be in P (Park) to turn the ignition switch
to LOCK/OFF.
The steering can bind with the wheels turned off center.
If this happens, move the steering wheel from right
to left while turning the key to ACC/ACCESSORY.
If this doesn’t work, then the vehicle needs service.
Notice:Using a tool to force the key to turn in
the ignition could cause damage to the switch or
break the key. Use the correct key, make sure it is
all the way in, and turn it only with your hand.
If the key cannot be turned by hand, see your
dealer/retailer.
B (ACC/ACCESSORY):This position lets things like
the radio and the windshield wipers operate while
the engine is off. Use this position if the vehicle must
be pushed or towed.
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C (ON/RUN):This position can be used to operate the
electrical accessories and to display some instrument
panel cluster warning and indicator lights. The switch
stays in this position when the engine is running.
The transmission is also unlocked in this position
on automatic transmission vehicles.
If you leave the key in the ACC/ACCESSORY or ON/
RUN position with the engine off, the battery could be
drained. You may not be able to start the vehicle if the
battery is allowed to drain for an extended period of time.
D (START):This is the position that starts the engine.
When the engine starts, release the key. The ignition
switch returns to ON/RUN for driving.
A warning tone will sound when the driver door is
opened, the ignition is in ACC/ACCESSORY or
LOCK/OFF and the key is in the ignition.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 door is opened.
Starting the Engine
Move the shift lever to P (Park) or N (Neutral).
The engine will not start in any other position.
To restart the engine when the vehicle is already
moving, use N (Neutral) only.
Notice:Do not try to shift to P (Park) if the
vehicle is moving. If you do, you could damage
the transmission. Shift to P (Park) only when the
vehicle is stopped.
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Starting Procedure
1. With your foot off the accelerator pedal, turn the
ignition to START. When the engine starts, let go of
the key. The idle speed will slow down as the engine
warms. 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.
The 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, 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, repeat these steps.
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.
Notice:The engine is designed to work with the
electronics in the vehicle. If you add electrical parts
or accessories, you could change the way the
engine operates. Before adding electrical equipment,
check with your dealer/retailer. If you do not, the
engine might not perform properly. Any resulting
damage would not be covered by the vehicle
warranty.
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Engine Coolant Heater
The engine heater can provide easier starting and better
fuel economy during engine warm-up in cold weather
conditions at or below 0°F (−18°C). Vehicles with an
engine heater should be plugged in at least four hours
before starting. An internal thermostat in the plug-end of
the cord may exist which will prevent engine coolant
heater operation at temperatures above 0°F (−18°C).
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Locate the electrical cord near the front recovery
loop on the driver side of the vehicle.
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.
The length of time the heater should remain plugged
in depends on several factors. Ask a dealer/retailer
in the area where you will be parking the vehicle for
the best advice on this.
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Automatic Transmission Operation
The 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.
P (Park):This position locks the rear wheels. It is the
best position to use when starting the engine because
the 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 P (Park). See Torque Lock (Automatic
Transmission) underShifting Into Park on page 2-43
for more information.{CAUTION:
It is dangerous to get out of the vehicle if the shift
lever is not fully in P (Park) with the parking brake
rmly set. The vehicle can roll.
Do not leave the 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 the
vehicle will not move, even when you are on fairly
level ground, always set the parking brake and
move the shift lever to P (Park). SeeShifting Into
Park on page 2-43. If you are pulling a trailer, see
Towing a Trailer on page 4-55.
R (Reverse):Use this gear to back up.
Notice:Shifting to R (Reverse) while the vehicle is
moving forward could damage the transmission.
The repairs would not be covered by the vehicle
warranty. Shift to R (Reverse) only after the vehicle
is stopped.
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To rock the vehicle back and forth to get out of snow,
ice, or sand without damaging the transmission, seeIf
Your Vehicle is Stuck in Sand, Mud, Ice, or Snow on
page 4-39.
N (Neutral):In this position, the engine does not
connect with the wheels. To restart the engine when
the vehicle is already moving, use N (Neutral) only.
Also, use N (Neutral) when the vehicle is being towed.
{CAUTION:
Shifting into a drive gear while the engine is
running at high speed is dangerous. Unless your
foot is rmly on the brake pedal, the vehicle could
move very rapidly. You could lose control and hit
people or objects. Do not shift into a drive gear
while the engine is running at high speed.
Notice:Shifting out of P (Park) or N (Neutral) with
the engine running at high speed may damage the
transmission. The repairs would not be covered by
the vehicle warranty. Be sure the engine is not
running at high speed when shifting the vehicle.D (Drive):This position is for normal driving. It provides
the best fuel economy. If you need more power for
passing, and you are:
Going less than about 35 mph (55 km/h), push the
accelerator pedal about halfway down.
Going about 35 mph (55 km/h) or more, push the
accelerator all the way down.
By doing this, the vehicle shifts down to the next gear
and has more power.
D (Drive) 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 a lower gear
selection if the transmission shifts too often.
Downshifting the transmission in slippery road conditions
could result in skidding, see Skidding underLoss of
Control on page 4-13.
M (Manual Mode):This position lets the driver select
the range of gears appropriate for current driving
conditions. If the vehicle has this feature, see Driver
Shift Control (DSC) later in this section.
Notice:Spinning the tires or holding the vehicle in
one place on a hill using only the accelerator pedal
may damage the transmission. The repair will not be
covered by the vehicle warranty. If you are stuck, do
not spin the tires. When stopping on a hill, use the
brakes to hold the vehicle in place.
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2 (Second):This position reduces vehicle speed
without using the brakes. Use 2 (Second) on hills.
It can help control vehicle speed as you go down steep
mountain roads, but then you may also want to use
the brakes off and on.
1 (First):This position reduces vehicle speed without
using the brakes. Use it for major/severe downgrades
and off-road driving where the vehicle would otherwise
accelerate due to steepness of grade.
When you shift to 2 (Second) or 1 (First) it provides
the lowest gear appropriate to your current road speed
and continues to downshift as the vehicle slows,
eventually downshifting to the selected gear.
The vehicle has a shift stabilization feature that adjusts
the transmission shifting to the current driving conditions
in order to reduce rapid upshifts and downshifts. This shift
stabilization feature is designed to determine, before
making an upshift, if the engine will be able to maintain
vehicle speed by analyzing things such as vehicle speed,throttle position and vehicle load. If the shift stabilization
feature determines that a current vehicle speed cannot be
maintained, the transmission does not upshift and instead
holds the current gear. In some cases, this may appear to
be a delayed shift, however the transmission is operating
normally.
The transmission uses adaptive shift controls that
compares key shift parameters to pre-programmed
ideal shifts stored in the transmission’s computer.
The transmission constantly makes adjustments to
improve vehicle performance according to how the
vehicle is being used, such as with a heavy load or
when the temperature changes. During this adaptive
shift control process, shifting may feel different as the
transmission determines the best settings.
When temperatures are very cold, the Hydra-Matic
®
6L80 automatic transmission’s gear shifting may
be delayed providing more stable shifts until the engine
warms up. Shifts may be more noticeable with a cold
transmission. This difference in shifting is normal.
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Tow/Haul Mode
The vehicle has a tow/haul mode. The tow/haul mode
adjusts the transmission shift pattern to reduce shift
cycling, providing increased performance, vehicle
control, and transmission cooling while towing or
hauling heavy loads.
Press the button located on the instrument panel to the
right of the steering wheel to turn tow/haul on or off. While
tow/haul is on, a light on the instrument panel cluster
comes on.
SeeTow/Haul Mode Light on page 3-44for more
information.
Also see “Tow Haul Mode” underTowing a Trailer on
page 4-55for more information.
Grade Braking
Grade Braking is only active while the Tow/Haul Mode is
selected and you are not in the Range Selection Mode.
See “Tow/Haul Mode listed previously andAutomatic
Transmission Operation on page 2-32for more
information on the Range Selection Mode. Grade Braking
assists in maintaining desired vehicle speeds when
driving on downhill grades by automatically implementing
a shift schedule that utilizes the engine and transmission
to slow the vehicle. This reduces wear on the braking
system and increases control of the vehicle. Grade
Braking monitors vehicle speed, acceleration, engine
torque and brake pedal usage. Using this information,
it detects when the truck is on a downhill grade and the
driver desires to slow the vehicle by pressing the brake.
Also seeTowing a Trailer on page 4-55for more
information.
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Cruise Grade Braking
Cruise Grade Braking operates while Cruise Control
is engaged in Tow/Haul mode to assist in maintaining
vehicle speed under loaded vehicle conditions. Cruise
Grade Braking assists when driving on a downhill grade.
It maintains vehicle speed by automatically implementing
a shift schedule that uses the engine and the
transmission to slow the vehicle. If vehicle speed is
above the desired speed the transmission will downshift
to slow the vehicle. If vehicle speed is near or below
desired speed the trans will upshift, allowing vehicle
speed to increase.
While in the Range Select Mode (RSM) mode, cruise
grade braking is not available.
SeeAutomatic Transmission Operation on page 2-32.
Full-Time Four-Wheel Drive
The Full-Time Four-Wheel Drive transfer case is
designed to constantly send the 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 the vehicle
powertrain and tires. Do not drive in Four-Wheel
High Lock or Four-Wheel Low Lock on pavement
for extended periods.
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N (Neutral):Shift the transfer case to N (Neutral) only
when towing the vehicle. SeeRecreational Vehicle
Towing on page 4-50orTowing Your Vehicle on
page 4-50for more information.
Indicator lights in the dial 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, take the 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 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 the vehicle to your dealer/retailer for service.
See “Service 4WD message” underDriver Information
Center (DIC) on page 3-46.
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 ON/RUN and the vehicle must be stopped or moving
less than 3 mph (5 km/h) with the transmission in
N (Neutral). The preferred method for shifting into
Four-Wheel Low Lock is to have the 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 the
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 3-56
for 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 the vehicle to have engagement noise
and bump when shifting between Four-Wheel Low Lock,
Full-Time Four-Wheel Drive or Four-Wheel-High Lock
ranges or from N (Neutral) with the engine running.
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