engine CHEVROLET TAHOE 2009 3.G Owner's Guide

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 3-64.Battery Run-Down Protection
This feature shuts off the dome, and reading lamps
if they are left on for more than 10 minutes when
the ignition is off. This will keep the battery from
running down.
Accessory Power Outlet(s)
Accessory power outlets can be used to connect
auxiliary electrical equipment, such as a cellular
telephone.
There are two under the climate controls, one inside the
center oor console, one on the rear of the center
oor console and one accessory power outlet in the rear
cargo area on the passenger side.
To use an accessory power outlet, remove the protective
cap. When not in use, always cover the accessory
power outlet with the protective cap.
The accessory power outlets are powered, even with
the ignition off. Continuing to use accessory power
outlets while the ignition is in LOCK/OFF may cause the
vehicle’s battery to run down.
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-(Defog):The defog mode is used to clear the
windows of fog or moisture. Air is directed to the
windshield, oor outlets, and side window vents. In this
mode, the system turns off recirculation and runs
the air conditioning compressor unless the outside
temperature is close to freezing. The recirculation mode
cannot be selected while in the defog mode.
0(Defrost):The defrost mode is used to remove fog
or frost from the windshield more quickly. Air is
directed to the windshield and side window vents, with
some directed to the oor vents. In this mode, the
system automatically forces outside air into the vehicle.
The recirculation mode cannot be selected while in
the defrost mode. The air conditioning compressor runs
automatically in this setting, unless the outside
temperature is close to freezing.
Do not drive the vehicle until all the windows are clear.
#(Air Conditioning):Press this button to turn the
air conditioning system on or off. An indicator light
comes on to show that the air conditioning is on. The air
conditioning can be selected in any mode as long as
the fan switch is on.
On hot days, open the windows to let hot inside air
escape; then close them. This helps to reduce the time
it takes for the vehicle to cool down. It also helps the
system to operate more efficiently.The air conditioning system removes moisture from the
air, so a small amount of water might drip under the
vehicle while idling or after turning off the engine. This is
normal.
h(Recirculation):Press this button to turn the
recirculation mode on or off. An indicator light comes on
to show that recirculation is on.
This mode recirculates and helps to quickly cool the air
inside the vehicle. It can be used to help prevent
outside air and odors from entering the vehicle.
The recirculation mode cannot be used with oor,
defrost, or defogging modes. If recirculation is selected
while in one of those modes, the indicator ashes
three times and turns off. The air conditioning
compressor will also come on when this mode is
activated. While in recirculation mode the windows may
fog when the weather is cold and damp. To clear the
fog, select either the defog or defrost mode and increase
the fan speed. The recirculation mode can also be
turned off by turning off the engine.
REAR:Press to turn the rear heating and air
conditioning on. SeeRear Air Conditioning and Heating
System on page 3-31orRear Air Conditioning and
Heating System and Electronic Climate Controls
on page 3-32for more information.
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Rear Window Defogger
The rear window defogger uses a warming grid to
remove fog from the rear window.
<(Rear Window Defogger):Press this button to
turn the rear window defogger on or off. The system
automatically turns off several minutes after it has been
activated. The defogger can also be turned off by
turning off the engine. Do not drive the vehicle until all
the windows are clear.
For vehicles with heated outside rearview mirrors, the
mirrors will heat to help clear fog or frost from the
surface of the mirror when the rear window defog button
is pressed.
Notice:Do not use anything sharp on the inside of
the rear window. If you do, you could cut or
damage the warming grid, and the repairs would not
be covered by the vehicle warranty. Do not attach
a temporary vehicle license, tape, a decal or
anything similar to the defogger grid.
Dual Automatic Climate Control
System
The heating, cooling, and ventilation in the vehicle can
be controlled with this system. The vehicle also has
a ow-through ventilation system described later in this
section.
If this vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
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The passenger’s temperature setting can be set to
match the driver’s temperature setting by pressing the
PASS button and turning off the PASS indicator.
When the passenger’s temperature setting is set
different than the driver’s setting, the indicator on the
PASS button illuminates and both the driver side
and passenger side temperature displays are shown.
Automatic Operation
AUTO (Automatic):When automatic operation is
active the system will control the inside temperature, the
air delivery, and the fan speed.
Use the steps below to place the entire system in
automatic mode:
1. Press the AUTO button.
When AUTO is selected, the display will change to
show the current temperature(s) and AUTO will
be lit on the display. The current delivery mode and
fan speed will also be displayed for approximately
5 seconds.
When AUTO is selected, the air conditioning
operation and air inlet will be automatically
controlled. The air conditioning compressor will run
when the outside temperature is over about
40°F (4°C). The air inlet will normally be set to
outside air. If it is hot outside, the air inlet mayautomatically switch to recirculate inside air to help
quickly cool down the vehicle. The light on the
button comes on in recirculation.
2. Set the driver’s and passenger’s temperature.
To nd your comfort setting, start with a 74°F (23°C)
temperature setting and allow about 20 minutes
for the system to regulate. Use the driver’s or
passenger’s temperature buttons to adjust the
temperature setting as necessary. If a temperature
setting of 60°F (15°C) is chosen, the system
remains at the maximum cooling setting. If a
temperature setting of 90°F (32°C) is chosen, the
system remains at the maximum heat setting.
Choosing either maximum setting will not cause the
vehicle to heat or cool any faster.
Do not to cover the solar sensor located on the top of
the instrument panel near the windshield. This
sensor regulates air temperature based on sun load and
also turns on the headlamps. For more information on
the solar sensor, see “Sensors” later in this section.
To avoid blowing cold air in cold weather, the system will
delay turning on the fan until warm air is available.
The length of delay depends on the engine coolant
temperature. Pressing the fan switch will override this
delay and change the fan to a selected speed.
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#(Air Conditioning):Press to turn the air conditioning
(A/C) compressor on and off. An indicator light comes on
to show that the air conditioning is on.
If this button is pressed when the air conditioning
compressor is unavailable, the indicator ashes three
times and then turns off. If the air conditioning is on and
the outside temperature drops below a temperature
which is too cool for air conditioning to be effective, the air
conditioning light turns off to show that the air
conditioning mode has been canceled.
On hot days, open the windows long enough to let hot
inside air escape. This helps to reduce the time it takes
for the vehicle to cool down. It also helps the system to
operate more efficiently.
The air conditioning system removes moisture from the
air, so a small amount of water might drip under the
vehicle while idling or after turning off the engine. This is
normal.
@(Recirculation):Press to turn the recirculation
mode on or off. An indicator light comes on to show that
the recirculation is on.This mode recirculates and helps to quickly cool the air
inside the vehicle. It can be used to help prevent
outside air and odors from entering the vehicle.
The recirculation mode cannot be used with oor, defog,
or defrost modes. If recirculation is selected with one
of those modes, the indicator light ashes three
times and then turns off. The air conditioning
compressor also comes on when this mode is activated.
While in recirculation mode the windows may fog
when the weather is cold and damp. To clear the fog,
select either the defog or defrost mode and increase the
fan speed.
The recirculation mode can also be turned off by turning
off the ignition.
REAR:For vehicles with the rear heat and air
conditioning controls. Press to turn the rear climate
control system on or off. SeeRear Air Conditioning and
Heating System and Electronic Climate Controls on
page 3-32.
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Rear Window Defogger
The rear window defogger uses a warming grid to
remove fog from the rear window.
<(Rear Window Defogger):Press to turn the rear
window defogger on or off. It automatically turns off
several minutes after it has been activated. The defogger
can also be turned off by turning off the engine. Do not
drive the vehicle until all the windows are clear.
Notice:Do not use a razor blade or sharp object to
clear the inside rear window. Do not adhere
anything to the defogger grid lines in the rear glass.
These actions may damage the rear defogger.
Repairs would not be covered by your warranty.
Heated Mirrors:For vehicles with heated outside
rearview mirrors, the mirrors heat to help clear fog or
frost from the surface of the mirror when the rear window
defog button is pressed. SeeOutside Power Mirrors
on page 2-53.
Sensors
The solar sensor, located in the defrost grille in the
middle of the instrument panel, monitors the solar heat.
Do not cover the solar sensor or the system will not
work properly.
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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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Speedometer and Odometer
The speedometer shows the vehicle’s speed in both
miles per hour (mph) and kilometers per hour (km/h).
The odometer shows how far the vehicle has been
driven, in either miles (used in the United States)
or kilometers (used in Canada).
Trip Odometer
The trip odometer can show how far the vehicle has
been driven since the trip odometer was last set to zero.
Press the reset button, located on the instrument
panel cluster next to the trip odometer display, to toggle
between the trip odometer and the regular odometer.
Holding the reset button for approximately one second
while the trip odometer is displayed resets it.
To display the odometer reading with the ignition off,
press the reset button.
Tachometer
The tachometer displays the engine speed in revolutions
per minute (rpm).
Safety Belt Reminders
Safety Belt Reminder Light
When the engine is started, a chime sounds for
several seconds to remind a driver to fasten the safety
belt, unless the driver safety belt is already buckled.
The safety belt light comes
on and stays on for
several seconds, then
ashes for several more.
This chime and light are repeated if the driver remains
unbuckled and the vehicle is in motion. If the driver’s
safety belt is already buckled, neither the chime nor the
light comes on.
Passenger Safety Belt Reminder Light
Several seconds after the engine is started, a chime
sounds for several seconds to remind the front passenger
to buckle their safety belt. This only occurs if the
passenger airbag is enabled. SeePassenger Sensing
System on page 1-90for more information. The
passenger safety belt light, located on the instrument
panel, comes on and stays on for several seconds and
then ashes for several more.
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This chime and light are
repeated if the passenger
remains unbuckled and
the vehicle is in motion.
If the passenger safety belt is buckled, neither the
chime nor the light comes on.
The front passenger safety belt warning light and chime
may turn on if an object is put on the seat such as a
briefcase, handbag, grocery bag, laptop or other
electronic device. To turn off the warning light and or
chime, remove the object from the seat or buckle
the safety belt
Airbag Readiness Light
The system checks the airbag’s electrical system for
possible malfunctions. If the light stays on it indicates
there is an electrical problem. The system check includes
the airbag sensor, the pretensioners, the airbag modules,
the wiring and the crash sensing and diagnostic module.
For more information on the airbag system, seeAirbag
System on page 1-81.The airbag readiness light
ashes for a few seconds
when the engine is
started. If the light does
not come on then, have it
xed immediately.
{CAUTION:
If the airbag readiness light stays on after the
vehicle is started or comes on while driving, it
means the airbag system might not be working
properly. The airbags in the vehicle might not
inate in a crash, or they could even inate
without a crash. To help avoid injury, have the
vehicle serviced right away.
If there is a problem with the airbag system, an airbag
Driver Information Center (DIC) message can also come
on. SeeDIC Warnings and Messages on page 3-64
for more information.
3-37

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. See
DIC Warnings and Messages on page 3-64for 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.
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
may 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 may also read low during the fuel
economy mode, this is normal.
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