2008 HUMMER H3 light

If you have an automatic transmission, the ignition
switch cannot be turned to LOCK/OFF unless the shift
lever is in PARK (P).
If the steering wheel is locked, move it from right to
left and turn the key to ACC/ACCESSORY. If none of
this works, then your vehicle needs service.
(B) ACC/ACCESSORY:This is the position in which
you can operate your electrical accessories or items
plugged into the accessory power outlets. On automatic
transmission vehicles, this position unlocks the
ignition. On manual transmission vehicles, it unlocks the
ignition and steering wheel. Use this position if your
vehicle must be pushed or towed.
(C) ON/RUN:This is the position that the switch returns
to after you start your engine and release the switch.
The switch stays in ON when the engine is running.
But even when the engine is not running, you can use
ON/RUN to operate the electrical accessories and
to display some instrument panel cluster warning and
indicator lights. The transmission is also unlocked in
this position on automatic transmission vehicles.
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.START (D):This is the position that starts the engine.
When the engine starts, release the key. The ignition
switch returns to ON/RUN for driving.
When the engine is not running, ACC/ACCESSORY
and ON/RUN allows you to operate the electrical
accessories, such as the radio or items plugged into
the accessory power outlets.
A warning tone will sound if you open the driver’s
door when the ignition is in ACC/ACCESSORY or
LOCK/OFF and the key is in the ignition.
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.
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Up-Shift Light
This light will show you
when to shift to the next
higher gear for best
fuel economy.
When this light comes on, you can shift to the next
higher gear if weather, road and traffic conditions permit.
For the best fuel economy, accelerate slowly and shift
when the light comes on.
While you accelerate, it is normal for the light to go
on and off if you quickly change the position of
the accelerator. Ignore the shift light when you
downshift.
If your vehicle has four-wheel drive and has a manual
transmission, disregard the shift light when the transfer
case is in four-wheel low.
For more information, seeUp-Shift Light on page 3-32.
Shift Speeds
{CAUTION:
If you skip a gear when you downshift, you
could lose control of your vehicle. You could
injure yourself or others. Do not shift down
more than one gear at a time when you
downshift.
Full-Time Four-Wheel Drive
Full-Time Four-Wheel Drive sends 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.
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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.
You can choose between four modes:
4
m(Four-Wheel High):This setting is used for driving
in most street and highway situations. You can also
use this setting for light or variable off-road conditions.
N (NEUTRAL):Shift the vehicle’s transfer case to
NEUTRAL only when towing your vehicle. See
Recreational Vehicle Towing on page 4-48orTowing
Your Vehicle on page 4-48for more information.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.
4
mQ(Four-Wheel-High Lock):Use this mode
when you need extra traction in most off-road situations
such as sand, mud, snow or level, rocky trails.
Notice:Operating your vehicle in
Four-Wheel-Low Lock above 30 mph (48 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 30 mph (48 km/h) for
extended periods.
4
nQ(Four-Wheel-Low Lock):This mode delivers
extra torque to all four wheels and is used for extreme
off-road conditions. You might choose 4-Wheel-Low
Lock if you are driving in off-road situations, such as,
deep sand, mud, or snow and climbing or descending
steep hills.
If the vehicle has a locking rear axle, 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.
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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 the mode the vehicle is in
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 lit 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 SERV 4WD message on the Driver Information
Center (DIC) stays on, you should take your vehicle to
your dealer for service. See Service 4WD message
underDIC Warnings and Messages on page 3-43.
Shifting between Four-Wheel High
and Four-Wheel-High Lock
With the vehicle traveling less than 45 mph
(72 km/h), press and release the Four-Wheel High
or Four-Wheel-High Lock button. The indicator light
will ash while shifting. It will remain lit when the
shift is complete.
It may be necessary to drive backwards while turning
for a distance of 25 feet (7.5 m) to get the lock
feature to disengage.
Shifting into Four-Wheel Low Lock
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.
To shift into Four-Wheel-Low Lock, the ignition must be in
ON 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.
If your vehicle has a manual transmission, the clutch
pedal must be pressed to the oor while you press the
Four-Wheel-Low Lock button, or the shift will not be
completed. You must wait for the Four-Wheel-Low Lock
indicator light to stop ashing and remain lit before
shifting your transmission in gear.
It is normal for your vehicle to have engagement noise
and bump when shifting between Four-Wheel Low
and Four-Wheel High 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 too fast, 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 last chosen setting.
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Shifting Out of Four-Wheel-Low Lock
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.
To shift out of Four-Wheel-Low 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 ON. 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. If your vehicle has a
manual transmission, the clutch pedal must be pressed
to the oor while you press the Four-Wheel High or
Four-Wheel-High Lock button, or the shift will not be
completed. 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 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
too fast, the Four-Wheel High or Four-Wheel-High Lock
indicator light will ash for 15 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).
Shifting Into NEUTRAL
To shift the transfer case to NEUTRAL, do the following:
1. Set the parking brake.
2. Start the vehicle by turning the ignition to START.
3. Put the transmission in NEUTRAL (N). If your
vehicle has a manual transmission, press and
hold the clutch pedal down while you perform
Steps 5 through 9.
4. Shift the transfer case to Four-Wheel High.
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{CAUTION:
Shifting an all-wheel-drive vehicle’s transfer
case into NEUTRAL can cause your vehicle to
roll even if the automatic transmission is in
PARK (P) or the manual transmission is in
any gear. You or others could be injured.
Make sure the parking brake is rmly set
before you shift the transfer case to NEUTRAL.
5. 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.
6. Press and hold the regular brake pedal and Shift
the transmission to REVERSE (R) for one second,
then shift the transmission for one second to
DRIVE (D) for an automatic transmission, or
FIRST (1) for vehicles have a manual transmission
and then let out the clutch. This is to ensure the
transfer case is in NEUTRAL. If not, repeat
this procedure starting at Step 3.
7. Turn the engine off, by turning the key to ACC.8. Place the transmission shift lever in PARK (P) for
an automatic transmission, or FIRST (1) for
vehicles that have a manual transmission.
9. Turn the ignition to LOCK/OFF.Shifting Out of NEUTRAL
To shift out of NEUTRAL:
1. Set the parking brake and apply the regular
brake pedal.
2. Shift the transmission to NEUTRAL (N) for an
automatic transmission, or press the clutch pedal
for vehicles that have a manual transmission.
Then turn the ignition to ON with the engine off.
3. Press the button for the desired transfer case shift
position (Four-Wheel High, Four-Wheel-High Lock
or Four-Wheel-Low Lock).
After the transfer case has shifted out of
NEUTRAL the light will go out.
4. Release the parking brake.
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.
5. You may start the engine and shift the transmission
to the desired position.
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Parking Brake
The parking brake pedal is
located to the left of the
regular brake pedal,
near the driver’s door.
To set the parking brake, hold the regular brake pedal
down with your right foot. Push the parking brake
pedal down to its fully-applied position with your
left foot.
A chime will activate and the brake warning light,
located on the instrument panel, 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.
The chime will deactivate and the light will turn off
when the parking brake is set and the vehicle is
moving below 3 mph (5 km/h). SeeBrake System
Warning Light on page 3-33.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, directly rearward 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 4-50.
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Mirrors
Automatic Dimming Rearview
Mirror with OnStar
®, Compass
and Temperature Display
Your vehicle may have this feature. When on, the
automatic dimming mirror dims to the proper level to
minimize glare from lights behind you after dark.
The mirror has a dual display in the upper right corner
of the mirror face that shows the compass reading
and the outside temperature.
Control buttons for the OnStar
®system are at the
bottom of the mirror. SeeOnStar®System on page 2-48
for more information about the services OnStar®
provides.
Y:This button is used as a toggle for changing
displays and as an on/off toggle during a function.
Your vehicle may also have a Rear Vision Camera.
SeeRear Vision Camera on page 2-44for more
information.
Slide-Out Video Feature Enable
Press and holdYfor three seconds to toggle the
slide-out video feature on/off. An indicator light will turn
on at the time the slide-out video is enabled. If the
slide-out video feature is on, each time the vehicle is
put into reverse, the slide-out video screen will extend.
SeeRear Vision Camera on page 2-44for more
information.
The slide-out video feature will remain in the current
on/off state each time the ignition goes through its cycle.
Slide-Out Video Cleaning
The slide-out video has to be enabled before the
cleaning process can take place.
Press and holdYfor six seconds or until the lower
indicator light turns on.
While extended for cleaning, neither the screen nor
the camera will have power.
PressYbriey or wait 30 seconds to end cleaning.
The screen will then retract.
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