2008 CHEVROLET AVALANCHE cooling

To replace the battery in the RKE transmitter:
1. Separate the halves of the transmitter with a at,
thin object inserted into the notch on the side.
2. Remove the old battery. Do not use a metal object.
3. Insert the new battery, positive side facing down.
Replace with a CR2032 or equivalent battery.
4. Put the transmitter back together tightly.
Remote Vehicle Start
Your vehicle may have a remote starting feature.
This feature allows you to start the engine from outside
of the vehicle. It may also start up the vehicle’s
heating or air conditioning systems and rear window
defogger. Normal operation of the system will return
after the key is turned to the ON/RUN position.
If your vehicle has an automatic climate control system,
the climate control system will default to a heating or
cooling mode depending on the outside temperatures.
If your vehicle does not have an automatic climate control
system, the system will turn on at the setting the vehicle
was set to when the vehicle was last turned off.
During a remote start, if your vehicle has an automatic
climate control system and heated seats, the heated
seats will turn on during colder outside temperatures
and will shut off when the key is turned to ON/RUN.
If your vehicle does not have an automatic climate
control system, during remote start, you will need to
manually turn the heated seats on and off. SeeHeated
Seats on page 1-5for additional information.
2-7

When you want to open a rear door when the security
lock is on, do the following:
1. Unlock the door by lifting the rear door manual lock,
using the power door lock switch, or the Remote
Keyless Entry (RKE) transmitter, if the vehicle
has one.
2. Open the door from the outside.
To cancel the rear door security lock, do the following:
1. Unlock the door and open it from the outside.
2. Insert the key into the security lock slot and turn it
so the slot is in the vertical position.
Lockout Protection
This feature protects you from locking your key in the
vehicle when the key is in the ignition and a door
is open.
If the power lock switch is pressed when a door is open
and the key is in the ignition, all of the doors will lock
and then the driver’s door will unlock.
Midgate®
{CAUTION:
It can be dangerous to drive with the cargo
area covered and the tailgate and the Midgate®
open because carbon monoxide (CO) gas can
come into your vehicle. You can not see or
smell CO. It can cause unconsciousness and
even death. If you must drive with the cargo
covers on and the tailgate and Midgate
®
open or if electrical wiring or other cable
connections must pass through the seal
between the body and the Midgate
®:
Make sure all windows are shut.
Turn the fan on your heating or cooling
system to its highest speed on the setting
that brings in outside air. This will force
outside air into your vehicle. SeeDual
Automatic Climate Control System on
page 3-24.
If you have air outlets on or under the
instrument panel, open them all the way.
SeeEngine Exhaust on page 2-48.
2-12

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 3-59.
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.
This will help prevent the battery from running down.
3-19

Climate Controls
Climate Control System
The heating, cooling, defrost, defog and ventilation of
your vehicle can be controlled with this system.
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 directs half of the air to the
instrument panel outlets and to the oor outlets. The
ow can be divided between vent and oor outlets
depending upon where the knob is placed between the
settings. A little air is directed towards the windshield
and side window outlets. Cooler air is directed to
the upper outlets and warmer air to the oor outlets.
6(Floor):This mode directs most of the air to
the oor outlets, with some of the air directed to the
windshield, side window outlets, and second row oor
outlets. In this mode, the system will automatically select
outside air. Recirculation cannot be selected when in
Floor Mode.
The right knob can also be used to select defog or
defrost mode. For more information, see “Defogging
and Defrosting” later in this section.
By positioning the right knob between two modes,
a combination of those two modes is selected.
The air conditioning compressor will be on unless the
outside temperature is close to freezing.
9(Fan):Turn the left knob clockwise or
counterclockwise to increase or decrease the fan speed.
Turn the knob all the way counterclockwise to turn the
front system off.
:(Outside Air):Press this button to turn on the
outside air mode. When this mode is selected, air from
outside the vehicle will circulate throughout your vehicle.
An indicator light on the button comes on to show that it
is activated. The outside air mode can be used with
all modes, but it cannot be used with the recirculation
mode. Pressing this button again will cancel the
recirculation mode.
3-21

Dual Automatic Climate Control
System
With this system, you can control the heating, cooling
and ventilation in your vehicle. Your vehicle also has a
ow-through ventilation system described later in this
section.
You can select different climate control settings for the
driver and passengers.
Driver’s Side Temperature Control
The driver’s side temperature buttons are used to adjust
the temperature of the air coming through the system on
the driver’s side. The temperature can be adjusted even
if the system is turned off. This is possible since outside
air will always ow through the system as the vehicle is
moving forward unless it is set to recirculation mode.
See “Recirculation” later in this section.
Press the + or−buttons to increase or decrease the
cabin temperature. The driver side temperature display
will show the temperature setting decreasing or
increasing.
3-24

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 you choose
the temperature setting of 60°F (15°C), the system
will remain at the maximum cooling setting. If you
choose the temperature setting of 90°F (32°C), the
system will remain at the maximum heat setting.
Choosing either maximum setting will not cause the
vehicle to heat or cool any faster.
Be careful 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 your 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.O(On/Off):Press this button to turn off the climate
control system. Outside air will still enter the vehicle, and
will be directed to the oor. This direction can be changed
by pressing the mode button. Recirculation can be
selected once you have selected vent or bi-level mode.
The temperature can also be adjusted using either
temperature button. If you adjust the air delivery mode or
temperature settings with the system off, the display will
illuminate briey to show you the settings and then return
off. Press the on/off button or the up down arrows on the
fan switch, the defrost button, AUTO button, or the air
conditioning button to turn the system on when it is off.
3-26

Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
It also provides an indicator of how hard your vehicle is
working. During a majority of the operation, the gage
will read 210°F (100°C) or less. If you are 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 5-28.
Tire Pressure Light
This light comes on briey
when the engine is started.
This light will also come on when one or more of your
tires are signicantly underinated.
A tire pressure message in the Driver Information
Center (DIC), may accompany the light. SeeDIC
Warnings and Messages on page 3-59for more
information.
Stop and check your tires as soon as it is safe to do so.
If underinated, inate to the proper pressure.
SeeTires on page 5-56for more information.
If a problem is detected with the Tire Pressure Monitor
System, this light will ash for approximately 60 seconds
and then stay on solid for the remainder of the ignition
cycle. SeeTire Pressure Monitor System on page 5-65
for more information. United States
Canada
3-42

DRIVER DOOR OPEN
This message displays and a chime sounds if the driver
door is not fully closed and the vehicle is in a drive
gear. Stop and turn off the vehicle, check the door
for obstructions, and close the door again. Check
to see if the message still appears on the DIC.
ENGINE HOT A/C (Air Conditioning)
TURNED OFF
This message displays when the engine coolant
becomes hotter than the normal operating temperature.
SeeEngine Coolant Temperature Gage on page 3-42.
To avoid added strain on a hot engine, the air
conditioning compressor automatically turns off.
When the coolant temperature returns to normal,
the air conditioning compressor turns back on.
You can continue to drive your vehicle.
If this message continues to appear, have the system
repaired by your dealer/retailer as soon as possible
to avoid damage to the engine.
ENGINE OVERHEATED IDLE ENGINE
Notice:If you drive your vehicle while the engine
is overheating, severe engine damage may occur.
If an overheat warning appears on the instrument
panel cluster and/or DIC, stop the vehicle as soon
as possible. SeeEngine Overheating on page 5-28
for more information.
This message displays when the engine coolant
temperature is too hot. Stop and allow the vehicle to idle
until it cools down. SeeEngine Coolant Temperature
Gage on page 3-42.
SeeOverheated Engine Protection Operating Mode on
page 5-30for information on driving to a safe place
in an emergency.
ENGINE OVERHEATED STOP ENGINE
Notice:If you drive your vehicle while the engine
is overheating, severe engine damage may occur.
If an overheat warning appears on the instrument
panel cluster and/or DIC, stop the vehicle as soon as
possible. SeeEngine Overheating on page 5-28
for more information.
This message displays and a chime sounds if the
engine cooling system reaches unsafe temperatures for
operation. Stop and turn off the vehicle as soon as it
is safe to do so to avoid severe damage. This message
clears when the engine has cooled to a safe operating
temperature.
3-60