2008 CHEVROLET IMPALA climate control

Reading Lamps
The vehicle has reading lamps that also act as the
dome lamp. Press the button to turn them on and off.
Mirror Reading Lamps
Your vehicle has reading lamps on the rearview mirror.
Push the button to turn the reading lamps on and off.
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 put the charge back in. 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 loads are on: 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 or
Service Battery Charging System. 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 3-52.
3-19

Battery Run-Down Protection
This vehicle has a feature to help prevent the battery
from being drained, if the interior courtesy lamps,
reading/map lamps, visor vanity lamps or trunk lamp are
accidentally left on. If any of these lamps are left on,
they will automatically turn off after 10 minutes,
if the ignition is off. The lamps will not come back on
again until one of the following occurs:
The ignition is turned on.
The exterior lamps control is turned off,
then on again.
The headlamps will timeout after 10 minutes, if they are
manually turned on before the ignition is off.
Accessory Power Outlet(s)
Your vehicle has three 12-volt outlets which can be
used to plug in electrical equipment such as a cellular
telephone, a compact disc player, etc.
On vehicles with a center console, one outlet is located
at the rear of the console in the bottom of the bin
and two outlets are located at the front of the console
bin under the instrument panel. Lift the cover to access
the outlet. Close the cover when not using the outlet.
On vehicles without a center console, two are located
under the climate controls and another outlet for the
rear seat passengers is at the rear of the center
front seat. Remove the rubber cover to access the
outlets. When not using the outlet, make sure the cover
is closed.
Notice:Leaving electrical equipment plugged in for
an extended period of time while the vehicle is off
will drain the battery. Power is always supplied
to the outlets. Always unplug electrical equipment
when not in use and do not plug in equipment
that exceeds the maximum 20 ampere rating.
3-20

Climate Controls
Climate Control System
This vehicle may have a dual or single climate control
system. With this system you can control the heating,
cooling, defrost, defog and ventilation for the vehicle.
If this vehicle has heated seats, seeHeated Seats
on page 1-4.
Manual Operation
Turn the right knob clockwise or counterclockwise to
direct the airow inside of the vehicle.
To change the current mode, select one of the following:
H(Vent):This mode directs air to the instrument
panel outlets.
)(Bi-Level):This mode splits the air between the
instrument panel outlets and the oor outlets. Dual Zone with Optional Heated Seat Controls
Single Zone
3-22

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.
For quick cool down on hot days, do the following:
1. Select the vent mode.
2. Select A/C.
3. Select the coolest temperature for both zones.
4. Select the highest fan speeds.
5. When the coolest temperature is selected in the
A/C mode, the system automatically goes into the
recirculation mode to improve cooling. Press the
Outside Air or Recirculation button to turn off
the automatic recirculation. This feature stays off
until the climate control system is powered on again
or the vehicle has been turned off and on again.
Using these settings together for long periods of time
may cause the air inside the vehicle to become too dry.
To prevent this from happening, after the air inside
the vehicle has cooled, turn the recirculation mode off.
The air conditioning system removes moisture from
the air, so you may sometimes notice a small amount of
water dripping underneath your vehicle while idling or
after turning off the engine. This is normal.Defogging and Defrosting
Fog on the inside of the windows is a result of high
humidity (moisture) condensing on the cool window
glass. This can be minimized if the climate control
system is used properly. There are two modes to clear
fog or frost from your windshield. Use the defog
mode to clear the windows of fog or moisture and warm
the passengers. Use the defrost mode to remove fog
or frost from the windshield more quickly.
Do not drive the vehicle until all the windows are clear.
Turn the right knob clockwise to select the defog or
defrost mode.
-(Defog):This mode directs air equally to the
windshield and the oor outlets. When defog is selected,
the system turns off recirculation and runs the air
conditioning compressor unless the outside temperature
is below 40°F (4°C).
0(Defrost):This mode directs most of the air to the
windshield with some air to the side window vents and
the oor vents. When defrost is selected, the system
automatically forces outside air into the vehicle. The air
conditioning compressor will run automatically in this
setting, unless the outside temperature is below
40°F (4°C).
3-24

Passenger Compartment Air Filter
This vehicle has a passenger compartment particulate
air lter. It is located underneath the hood just below the
windshield wiper arm on the passenger’s side of the
vehicle, under the air inlet grille.
The lter traps most of the pollen from air entering the
Climate Control System. Like your engine’s air
cleaner/lter, it may need to be changed periodically to
ensure system performance. For information on how
often to change the passenger compartment air
lter, seeScheduled Maintenance on page 6-4.
To change the passenger compartment air lter, use the
following steps:
1. Turn off the ignition when the windshield wipers
are in the up position.
2. Raise the vehicle hood.
3. Peel back the hood weatherstrip from the
passenger’s side of the vehicle halfway to center.4. Remove the air inlet grille retainers.
5. Lift the air inlet grille and disconnect the washer
hose at the quick-connect.
6. Remove the air inlet grille.
7. Remove the water deector plate.
8. Remove the old passenger compartment air lter.
9. Reverse the steps to install the new air lter.
For best climate control system performance, be sure to
re-install the air lter.
For the type of lter to use, seeNormal Maintenance
Replacement Parts on page 6-13.
3-26

Compass Calibration
The compass can be manually calibrated. Only calibrate
the compass in a magnetically clean and safe location,
such as an open parking lot, where driving the vehicle
in circles is not a danger. It is suggested to calibrate
away from tall buildings, utility wires, manhole covers,
or other industrial structures, if possible.
If CAL should ever appear in the DIC display,
the compass should be calibrated.
If the DIC display does not show a heading, for example,
N for North, or the heading does not change after
making turns, there may be a strong magnetic eld
interfering with the compass. Such interference may be
caused by a magnetic CB or cell phone antenna
mount, a magnetic emergency light, magnetic note pad
holder, or any other magnetic item. Turn off the
vehicle, move the magnetic item, then turn on the
vehicle and calibrate the compass.To calibrate the compass, use the following procedure:Compass Calibration Procedure
1. Before calibrating the compass, make sure the
compass zone is set to the variance zone in
which the vehicle is located. See “Compass
Variance (Zone) Procedure” earlier in this section.
Do not operate any switches such as window,
sunroof, climate controls, seats, etc. during
the calibration procedure.
2. Press the vehicle information button until
PRESS
VTO CALIBRATE COMPASS displays.
3. Press the set/reset button to start the compass
calibration.
4. The DIC will display CALIBRATING: DRIVE IN
CIRCLES. Drive the vehicle in tight circles at
less than 5 mph (8 km/h) to complete the calibration.
The DIC will display CALIBRATION COMPLETE
for a few seconds when the calibration is complete.
The DIC display will then return to PRESS
VTO
CALIBRATE COMPASS.
3-51

SERVICE A/C (Air Conditioning)
SYSTEM
This message displays when the electronic sensors that
control the air conditioning and heating systems are
no longer working. Have the climate control system
serviced by your dealer/retailer if you notice a drop in
heating and air conditioning efficiency.
SERVICE AIR BAG
This message displays when there is a problem with the
airbag system. Have your vehicle serviced by your
dealer/retailer immediately. SeeAirbag Readiness Light
on page 3-31for more information.
SERVICE BATTERY CHARGING
SYSTEM
This message displays when there is a problem with the
generator and battery charging systems. Driving with
this problem could drain the battery. Turn off all
unnecessary accessories. Stop and turn off the vehicle
as soon as it is safe to do so. Have the electrical
system checked by your dealer/retailer immediately.
SERVICE BRAKE SYSTEM
This message displays when service is required on the
brake system. Have the brake system serviced by
your dealer/retailer as soon as possible. The brake
system warning light also appears on the instrument
panel cluster when this message appears on the DIC.
SeeBrake System Warning Light on page 3-34.
SERVICE POWER STEERING
This message displays when a problem is detected with
the power steering system. When this message is
displayed, you may notice that the effort required to
steer the vehicle increases or feels heavier, but you will
still be able to steer the vehicle. Have your vehicle
serviced by your dealer/retailer immediately.
SERVICE STABILITRAK
If your vehicle has Electronic Stability Control (ESC),
this message displays if there has been a problem
detected with ESC. The ESC/TCS light also appears on
the instrument panel cluster. SeeElectronic Stability
Control on page 4-7for more information.
If this message turns on while you are driving, pull off the
road as soon as possible and stop carefully. Try resetting
the system by turning the ignition off and then back on.
3-56

Uniform Tire Quality Grading
Quality grades can be found where applicable on
the tire sidewall between tread shoulder and
maximum section width. For example:
Treadwear 200 Traction AA Temperature A
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration (NHTSA), which
grades tires by treadwear, traction, and
temperature performance. This applies only to
vehicles sold in the United States. The grades are
molded on the sidewalls of most passenger car
tires. The Uniform Tire Quality Grading (UTQG)
system does not apply to deep tread, winter-type
snow tires, space-saver, or temporary use
spare tires, tires with nominal rim diameters of
10 to 12 inches (25 to 30 cm), or to some
limited-production tires.
While the tires available on General Motors
passenger cars and light trucks may vary with
respect to these grades, they must also conform
to federal safety requirements and additional
General Motors Tire Performance Criteria (TPC)
standards.
Treadwear
The treadwear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a specied
government test course. For example, a tire
graded 150 would wear one and a half (1.5) times
as well on the government course as a tire
graded 100. The relative performance of tires
depends upon the actual conditions of their use,
however, and may depart signicantly from the
norm due to variations in driving habits, service
practices, and differences in road characteristics
and climate.
Traction – AA, A, B, C
The traction grades, from highest to lowest, are AA,
A, B, and C. Those grades represent the tire’s
ability to stop on wet pavement as measured under
controlled conditions on specied government test
surfaces of asphalt and concrete. A tire marked C
may have poor traction performance.
Warning:The traction grade assigned to this tire is
based on straight-ahead braking traction tests,
and does not include acceleration, cornering,
hydroplaning, or peak traction characteristics.
5-73