2008 GMC ACADIA air conditioner

For quicker cool down on hot days, do the following:
1. Open the windows to let hot air escape.
2. Select the vent mode.
3. Select the air conditioner.
4. Select the coolest temperature.
5. Select the highest fan speed.
6. Close the windows after the hot air has escaped.
7. Once the vehicle’s interior temperature is below
the outside temperature, select recirculation
mode for better cooling.
This helps to reduce the time it takes for the vehicle
to cool down. It also helps the system to operate
more efficiently.
Using recirculation for long periods of time may
cause the air inside of the vehicle to become too dry.
To prevent this from happening, after the inside of
the vehicle has cooled, turn the recirculation mode off.
The air conditioning system removes moisture from
the air, so you might notice a small amount of water
dripping underneath the front center and right rear
of the 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 the windshield. Turn the right knob
clockwise to select the defog or defrost mode.
-(Defog):The defog mode is used to clear the
windows of fog or moisture and warm the passengers.
This mode directs air to the windshield, oor outlets,
and side window vents. When you select this mode,
the system turns off recirculation and runs the air
conditioning compressor unless the outside temperature
is less than 40°F (4°C). The recirculation mode
cannot be selected while in the defog mode. Do not
drive the vehicle until all the windows are clear.
0(Defrost):The defrost mode is used to remove fog
or frost from the windshield more quickly. This mode
directs most of the air to the windshield and side window
vents and some to the oor vents. In this mode, the
system will automatically force outside air into your
vehicle. The recirculation mode cannot be selected while
in the defrost mode. The air conditioning compressor
will run automatically in this setting, unless the outside
temperature is less than 40°F (4°C). Do not drive
the vehicle until all the windows are clear.
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Outlet Adjustment
Use the slider switch in the center of the outlet,
to change the direction of the air ow. Use the
thumbwheel near the outlet to control the amount
of air ow or to shut off the airow completely.
Keep all outlets open whenever possible for best
system performance.
Operation Tips
Clear away any ice, snow, or leaves from the
air inlets at the base of the windshield that can
block the ow of air into the vehicle.
Use of non-GM approved hood deectors can
adversely affect the performance of the system.
Keep the path under all seats clear of objects
to help circulate the air inside the vehicle more
effectively.
If fogging reoccurs while in vent or bi-level modes
with mild temperature throughout the vehicle, turn
on the air conditioner to reduce windshield fogging.
Rear Air Conditioning and
Heating System
If your vehicle has this system, the rear controls are
three knobs located on the rear of the center console.
The system can be controlled from the front controls
as well as the rear controls.
To turn the system on, press the AUX button on the
front climate control system, an indicator will be
lit. Pressing the AUX button the rst time will turn the
rear system on in a mimic mode. In this mode, the
airow in the rear will be approximately the same
direction, temperature, and fan speed as the front.
Pressing the AUX button again will turn the rear system
and the indicator off.
If the rear controls are adjusted, the system turns
on in a rear independent mode. Airow in the rear
will then be directed according to the settings of the
rear controls. The rear system can be turned off
by pressing the AUX button on the front climate control
system and the indicator will turn off. The system
can be turned back on, by adjusting any of the rear
air conditioning control knobs.
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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 passenger sensing
system. See your dealer/retailer for service.
{CAUTION:
If the airbag readiness light in the instrument
panel cluster ever comes on and stays on,
it means that something may be wrong with
the airbag system. If this ever happens, have
the vehicle serviced promptly, because an
adult-size person sitting in the right front
passenger’s seat may not have the protection
of the airbag(s). SeeAirbag Readiness Light
on page 3-42for more on this, including
important safety information.
Charging System Light
This light will come on
briey when you turn
on the ignition, but
the engine is not
running, as a check to
show you it is working.
It should go out once the engine is running. If it stays
on, or comes on while you are driving, you may have
a problem with the charging system. A charging system
Driver Information Center (DIC) message may also
appear. SeeDIC Warnings and Messages on page 3-66
for more information. This light could indicate that
you have problems with a generator drive belt, or
another electrical problem. Have it checked right away.
If you must drive a short distance with the light on,
be certain to turn off all your accessories, such as
the radio and air conditioner.
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If No Steam Is Coming From Your
Engine
If you get an engine overheat warning but see or hear
no steam, the problem may not be too serious.
Sometimes the engine can get a little too hot when you:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer.
If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. If your air conditioner is on, turn it off.
2. Turn on your heater to full hot at the highest fan
speed and open the windows as necessary.
3. If you are in a traffic jam, shift to NEUTRAL (N);
otherwise, shift to the highest gear while
driving — DRIVE (D) or LOW (L).
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning does not come back on, you can drive
normally.
If the warning continues, pull over, stop, and park your
vehicle right away.If there is still no sign of steam, idle the engine for three
minutes while you are parked. If you still have the
warning, turn off the engine and get everyone out of the
vehicle until it cools down. Also, see “Overheated
Engine Protection Operating Mode” later in this section.
You may decide not to lift the hood but to get service
help right away.
Overheated Engine Protection
Operating Mode
This emergency operating mode lets your vehicle be
driven to a safe place in an emergency situation. If an
overheated engine condition exists, an overheat
protection mode which alternates ring groups of
cylinders helps prevent engine damage. In this mode,
there is a signicant loss in power and engine
performance. The temperature gage indicates an
overheat condition exists. Driving extended distances
and/or towing a trailer in the overheat protection
mode should be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any
repair. The engine oil will be severely degraded.
Repair the cause of coolant loss, change the oil and
reset the oil life system. SeeEngine Oil on
page 5-15.
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