2009 HUMMER H2 warning light

Electric Power Management
The vehicle has Electric Power Management (EPM) that
estimates the battery’s temperature and state of charge.
It then adjusts the voltage for best performance and
extended life of the battery.
When the battery’s state of charge is low, the voltage is
raised slightly to quickly bring the charge back up. When
the state of charge is high, the voltage is lowered slightly
to prevent overcharging. If the vehicle has a voltmeter
gage or a voltage display on the Driver Information
Center (DIC), you may see the voltage move up or down.
This is normal. If there is a problem, an alert will be
displayed.
The battery can be discharged at idle if the electrical
loads are very high. This is true for all vehicles. This is
because the generator (alternator) may not be spinning
fast enough at idle to produce all the power that is
needed for very high electrical loads.
A high electrical load occurs when several of the
following are on, such as: headlamps, high beams, fog
lamps, rear window defogger, climate control fan at
high speed, heated seats, engine cooling fans, trailer
loads, and loads plugged into accessory power outlets.EPM works to prevent excessive discharge of the
battery. It does this by balancing the generator’s output
and the vehicle’s electrical needs. It can increase
engine idle speed to generate more power, whenever
needed. It can temporarily reduce the power demands
of some accessories.
Normally, these actions occur in steps or levels, without
being noticeable. In rare cases at the highest levels of
corrective action, this action may be noticeable to the
driver. If so, a Driver Information Center (DIC) message
might be displayed, such as BATTERY SAVER ACTIVE,
BATTERY VOLTAGE LOW, or LOW BATTERY. If this
message is displayed, it is recommended that the driver
reduce the electrical loads as much as possible. SeeDIC
Warnings and Messages on page 3-56.
Battery Run-Down Protection
This feature shuts off the dome lamps if they are left
on for more than 10 minutes when the ignition is
in LOCK/OFF. This helps to prevent the battery
from running down.
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Manual Operation
DC(Fan Control):Press these buttons on the rear
seat audio control panel to increase or decrease airow.
+/−(Temperature Control):Press these buttons
to adjust the temperature of the air owing into the
passenger area. Press the + button for warmer air
and press the−button for cooler air. The temperature
settings will display in 0-12 increments, going from
the coolest (0) to the warmest (12) setting.
N(Air Delivery Mode Control):Press the mode
button to change the direction of the airow in the
vehicle. Repeatedly press the button until the desired
mode appears on the display. Multiple presses will cycle
through the delivery selections.
Select from the following:
H(Vent):Air is directed to the headliner outlets.
)(Bi-Level):Air is directed to the oor outlets as well
as the headliner outlets. The rear system oor outlet
is located at the passenger side rear quarter trim panel.
6(Floor):Air is directed to the oor outlets.
The rear system oor outlets are located under
the seats.
Warning Lights, Gages, and
Indicators
Warning lights and gages can signal that something is
wrong before it becomes serious enough to cause
an expensive repair or replacement. Paying attention
to the warning lights and gages could prevent injury.
Warning lights come on when there may be or is
a problem with one of the vehicle’s functions. Some
warning lights come on briey when the engine is
started to indicate they are working.
Gages can indicate when there may be or is a problem
with one of the vehicle’s functions. Often gages and
warning lights work together to indicate a problem with
the vehicle.
When one of the warning lights comes on and stays on
while driving, or when one of the gages shows there may
be a problem, check the section that explains what to do.
Follow this manual’s advice. Waiting to do repairs can be
costly and even dangerous.
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{CAUTION:
If the airbag readiness light ever comes on and
stays on, it means that something may be wrong
with the airbag system. For example, the right
front passenger airbag could inate even though
the airbag on-off switch is turned off.
To help avoid injury to yourself or others, have the
vehicle serviced right away. SeeAirbag Readiness
Light on page 3-32for more information, including
important safety information.
If the word ON or the on symbol is lit, it means that
the right front passenger frontal airbag is enabled (may
inate). SeeAirbag Off Switch on page 1-76for more
information, including important safety information.
If, after several seconds, both status indicator lights
remain on, or if there are no lights at all, there may
be a problem with the lights or the airbag on-off switch.
See your dealer/retailer for service.
Charging System Light
This light comes on briey
when the ignition key is
turned to START, but the
engine is not running, as a
check to show it is working.
If it does not, have the vehicle serviced by your
dealer/retailer.
The light should go out once the engine starts. If it stays
on, or comes on while driving, there could be a problem
with the charging system. A charging system message
in the Driver Information Center (DIC) can also appear.
SeeDIC Warnings and Messages on page 3-56for
more information. This light could indicate that there are
problems with a generator drive belt, or that there is an
electrical problem. Have it checked right away. If the
vehicle must be driven a short distance with the light
on, turn off accessories, such as the radio and air
conditioner.
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Voltmeter Gage
When the engine is not
running, but the ignition
is on, this gage shows the
battery’s state of charge
in DC volts.
When the engine is running, the gage shows the
condition of the charging system. The charging system
regulates voltage based on the state of the battery for
improved fuel economy and battery life. The gage can
transition from a higher to lower or a lower to higher
reading. This is normal. Readings between the low
and high warning zones indicate the normal operating
range. The gage can also read low during the fuel
economy mode.Readings in the low warning zone can occur when
a large number of electrical accessories are operating
in the vehicle and the engine is left at an idle for an
extended period. This condition is normal since the
charging system is not able to provide full power at
engine idle. As engine speeds are increased, this
condition should correct itself as higher engine speeds
allow the charging system to create full power. If there
is a problem with the battery charging system, this light
comes on or the SERVICE BATTERY CHARGING
SYSTEM DIC message displays. SeeDIC Warnings
and Messages on page 3-56andCharging System
Light on page 3-35for more information.
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Brake System Warning Light
With the ignition on, the brake system warning light
comes on when the parking brake is set. If the vehicle is
driven with the parking brake engaged, a chime sounds
when the vehicle speed is greater than 5 mph (8 km/h).
The vehicle’s hydraulic brake system is divided into
two parts. If one part is not working, the other part
can still work and stop the vehicle. For good braking,
both parts need to be working well.
If the warning light comes on and a chime sounds there
could be a brake problem. Have the brake system
inspected right away.
This light can also come on due to low brake uid.
SeeBrakes on page 5-38for more information.This light comes on briey when the ignition key is
turned to ON/RUN. If it does not come on then, have it
xed so it is ready to warn if there is a problem.
{CAUTION:
The brake system might not be working properly if
the brake system warning light is on. Driving with
the brake system warning light on can lead to a
crash. If the light is still on after the vehicle has
been pulled off the road and carefully stopped,
have the vehicle towed for service.
If the light comes on while driving, pull off the road and
stop carefully. The pedal might be harder to push or
might go closer to the oor. It can take longer to stop.
If the light is still on, have the vehicle towed for service.
SeeTowing Your Vehicle on page 4-50.
United States
Canada
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Antilock Brake System (ABS)
Warning Light
For vehicles with
the Antilock Brake
System (ABS), this light
comes on briey when
the engine is started.
If it does not, have the vehicle serviced by your
dealer/retailer. If the system is working normally the
indicator light then goes off.
If the ABS light stays on, turn the ignition off. If the
light comes on while driving, stop as soon as it is safely
possible and turn the ignition off. Then start the engine
again to reset the system. If the ABS light stays on, or
comes on again while driving, the vehicle needs service.
If the regular brake system warning light is not on, the
vehicle still has brakes, but not antilock brakes. If the
regular brake system warning light is also on, the vehicle
does not have antilock brakes and there is a problem with
the regular brakes. SeeBrake System Warning Light on
page 3-37.
For vehicles with a Driver Information Center (DIC),
seeDIC Warnings and Messages on page 3-56for all
brake related DIC messages.
StabiliTrak®Indicator Light
For vehicles with the
StabiliTrak®system, this
light comes on briey while
starting the engine.
If it does not, have the vehicle serviced by your
dealer/retailer. If the system is working normally the
indicator light then goes off.
If the light comes on and stays on while driving, there
could be a problem with the StabiliTrak
®system and the
vehicle might need service. When this warning light is
on, the StabiliTrak
®system is off and does not limit
wheel spin.
The light ashes if the system is active and is working
to assist the driver with directional control of the
vehicle in difficult driving conditions.
SeeStabiliTrak
®System on page 4-6for more
information.
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Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
It also provides an indicator of how hard the vehicle is
working. During a majority of the operation, the gage
reads 210°F (100°C) or less. If the vehicle is pulling a
load or going up hills, it is normal for the temperature to
uctuate and approach the 250°F (122°C) mark. If the
gage reaches the 260°F (125°C) mark, it indicates that
the cooling system is working beyond its capacity.
SeeEngine Overheating on page 5-33.
Tire Pressure Light
For vehicles with a tire
pressure light, this light
comes on briey when
the engine is started.
It provides information about tire pressures and the
Tire Pressure Monitoring System.
When the Light is On Steady
This indicates that one or more of the tires is signicantly
underinated.
A tire pressure message in the Driver Information
Center (DIC), can accompany the light. SeeDIC
Warnings and Messages on page 3-56for more
information. Stop and check the tires as soon as it is
safe to do so. If a tire is underinated, inate to the
proper pressure. SeeTires on page 5-57for more
information. United States
Canada
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Notice:Lack of proper engine oil maintenance
can damage the engine. The repairs would not be
covered by the vehicle warranty. Always follow
the maintenance schedule in this manual for
changing engine oil.
The oil pressure gage shows the engine oil pressure
in psi (pounds per square inch) when the engine
is running. Canadian vehicles indicate pressure in
kPa (kilopascals).
Oil pressure can vary with engine speed, outside
temperature and oil viscosity, but readings above
the low pressure zone indicate the normal operating
range. When the oil pressure reaches the low pressure
zone, the OIL PRESSURE LOW STOP ENGINE
message appears in the Driver Information Center (DIC).
SeeDIC Warnings and Messages on page 3-56and
Engine Oil on page 5-15for more information.
A reading in the low pressure zone can be caused
by a dangerously low oil level or some other problem
causing low oil pressure. Check the oil as soon as
possible.Oil Pressure Light
{CAUTION:
Do not keep driving if the oil pressure is low.
The engine can become so hot that it catches re.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.
Notice:Lack of proper engine oil maintenance
can damage the engine. The repairs would not be
covered by the vehicle warranty. Always follow
the maintenance schedule in this manual for
changing engine oil.
This light comes on briey while starting the engine.
If it does not, have the vehicle serviced by your
dealer/retailer. If the system is working normally
the indicator light then goes off.
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