2003 CHEVROLET AVALANCHE engine overheat

Engine Coolant Heater
Your vehicle may be equipped with an engine coolant
heater.
In very cold weather, 0ÉF
(-18ÉC) or colder, the
engine coolant heater can
help. You'll get easier
starting and better
fuel economy during
engine warm-up.
Usually, the coolant heater should be plugged in a
minimum of four hours prior to starting your vehicle. At
temperatures above 32ÉF (0ÉC), use of the coolant
heater is not required.
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord. The
cord is located on the driver's side of the engine
compartment, near the power steering ¯uid reservoir.3. Plug it into a normal, grounded 110-volt AC outlet.
{CAUTION:
Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the
wrong kind of extension cord could overheat
and cause a ®re. You could be seriously
injured. Plug the cord into a properly grounded
three-prong 110-volt AC outlet. If the cord
won't reach, use a heavy-duty three-prong
extension cord rated for at least 15 amps.
4. Before starting the engine, be sure to unplug and
store the cord as it was before to keep it away
from moving engine parts. If you don't, it could be
damaged.
How long should you keep the coolant heater plugged
in? The answer depends on the outside temperature, the
kind of oil you have, and some other things. Instead
of trying to list everything here, we ask that you contact
your dealer in the area where you'll be parking your
vehicle. The dealer can give you the best advice for that
particular area.
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If you manually select SECOND (2), the transmission
will drive in second gear. You may use this feature
for reducing the speed of the rear wheels when you are
trying to start your vehicle from a stop on slippery
road surfaces. Once the vehicle is moving, shift into
DRIVE (D).
FIRST (1):This position gives you even more power,
but lower fuel economy than SECOND (2). You can use
it on very steep hills, or in deep snow or mud. If the
shift lever is put in FIRST (1) while the vehicle is moving
forward, the transmission won't shift into ®rst gear
until the vehicle is going slowly enough.
Notice:If your wheels won't turn, don't try to drive.
This might happen if you were stuck in very deep
sand or mud or were up against a solid object. You
could damage your transmission. Also, if you
stop when going uphill, don't hold your vehicle there
with only the accelerator pedal. This could overheat
and damage the transmission. Use your brakes
or shift into PARK (P) to hold your vehicle in
position on a hill.
On cold days, approximately 32ÉF (0ÉC) or colder, your
transmission is designed to shift differently until the
engine reaches normal operating temperature. This is
intended to improve heater performance.
Tow/Haul Mode
Your vehicle is equipped with a tow/haul mode. The
button is located on the end of the column shift lever.
You can use this feature to assist when towing or
hauling a heavy load. See ªTow/Haul Modeº under
Towing a Trailer on page 4-58for more information.
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·Move the lever up as far as it will go.
3. Be sure the transfer case is in a drive gear ± not in
NEUTRAL.
4. Turn the ignition key to LOCK.
5. Remove the key and take it with you. If you can
leave your vehicle with the ignition key in your
hand, your vehicle is in PARK (P).
Leaving Your Vehicle With the Engine
Running
{CAUTION:
It can be dangerous to leave your vehicle with
the engine running. Your vehicle could move
suddenly if the shift lever is not fully in PARK
(P) with the parking brake ®rmly set.
If you have four-wheel drive, your vehicle will
be free to roll ± even if your lever is in PARK
(P) ± if your transfer case is in NEUTRAL. So
be sure the transfer case is in a drive gear ±
not NEUTRAL. See ªFour-Wheel Drive
(Automatic Transfer Case)º in the Index.
And, if you leave the vehicle with the engine
running, it could overheat and even catch ®re.
You or others could be injured. Don't leave
your vehicle with the engine running unless
you have to.
If you have to leave your vehicle with the engine
running, be sure your vehicle is in PARK (P) and the
parking brake is ®rmly set before you leave it.
2-41

·If you move the shift lever to FIRST (1), the light
will come on and stay on to indicate that the
traction system is off. This is normal operation. To
turn the system back on, move the shift lever
back to a position other than FIRST (1); the light
should go off. See
Traction Assist System (TAS) on
page 4-10.
·The light will come on and stay on if the TAS
automatic engagement feature has been turned off.
To turn the system on, press the TAS off/on
button; the light should go off. To turn the automatic
engagement feature back on, see
Traction Assist
System (TAS) on page 4-10.
·If the Traction Assist System is affected by an
anti-lock brake system, TAS or engine-related
problem, the system will turn off and the light will
come on. Have your vehicle serviced.
·If the vehicle is driven over an extremely rough
road, the system will turn off and the light will come
on. The light will go off a few seconds after the
rough road conditions go away or when the vehicle
comes to a complete stop. This is normal
operation.
For more information on the traction off light and
Stabilitrak
ž, seeStabilitrakžSystem on page 4-12.
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 210ÉF (100ÉC) or less. If you are pulling a load
or going up hills, it is normal for the temperature to
¯uctuate and approach the 250ÉF (122ÉC) mark. If the
gage reaches the 260ÉF (125ÉC) mark, it indicates
that the cooling system is working beyond its capacity.
See
Engine Overheating on page 5-27. United States
Canada
3-39

Driver Information Center (DIC)
The DIC display is located on the instrument panel
cluster above the steering wheel. The DIC can display
information such as the trip odometer, fuel economy and
personalization features. Vehicles without the DIC
buttons will not have all the features as the regular DIC.
See
Speedometer and Odometer on page 3-32for
information on features for vehicles without a full DIC.
A (Trip Information):This button will display the
odometer, personal trip odometer, business trip
odometer, hourmeter, annual log and the timer.
B (Fuel Information):This button will display the
current range, average fuel economy, instant fuel
economy and engine oil life.C (Personalization):This button will change personal
options available on your vehicle.
D (Select):This button resets certain functions and
turns off or acknowledges messages on the DIC.
DIC Operation and Displays
The DIC comes on when the ignition is on. After a short
delay the DIC will display the current driver (1 or 2)
and the information that was last displayed before the
engine was turned off.
If a problem is detected, a warning message will appear
on the display. Pressing any of the four buttons will
acknowledge (clear) most current warnings or service
messages. Some warnings that cannot be
acknowledged (cleared) are: ENGINE OVERHEATED,
OIL PRESSURE LOW, REDUCED ENGINE POWER,
TRANS HOT IDLE ENGINE, STABILITY SYS ACTIVE,
TRACTION SYS LIMITED and TRACTION ACTIVE.
These warnings must be dealt with immediately
and therefore cannot be cleared until the problem has
been corrected.
The DIC has different modes which can be accessed by
pressing the four buttons on the DIC. These buttons
are trip information, fuel information, personalization and
select. The button functions are detailed in the
following.
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LOW COOLANT LEVEL
If the engine coolant level is low, this message will
appear on the DIC. Adding coolant will clear the
message. This message will clear itself after 10 seconds
until the next igntion cycle.
ENGINE COOLANT HOT
If the cooling system temperature gets hot, this message
will appear in the DIC. Stop the vehicle and let the
engine idle in PARK (P) to allow the coolant to reach a
safe temperature. This message will clear when the
coolant temperature drops to a safe operating
temperature. Pressing the select button will
acknowledge this message and clear it from the DIC
display.
ENGINE OVERHEATED
If the engine cooling system reaches unsafe
temperatures for operation, this message will appear in
the DIC and you will hear a chime. Stop and turn off
the vehicle as soon as it is safe to do so to avoid severe
damage. This message will clear when the engine
has cooled to a safe operating temperature.
REDUCED ENGINE POWER
This message is displayed and a chime will sound when
the cooling system temperature gets too hot and the
engine further enters the engine coolant protection
mode.
See
Engine Overheating on page 5-27for further
information.
BATTERY NOT CHARGING
If the battery is not charging during operation, this
message will appear on the DIC. Driving with this
problem could drain your battery. Have the electrical
system checked as soon as possible. Pressing the
select button will acknowledge this message and clear it
from the DIC display.
SERVICE AIR BAG
If there is a problem with the air bag system, this
message will be displayed on the DIC. Have a quali®ed
technician inspect the system for problems. Pressing
the select button or the trip stem will acknowledge this
message and clear it from the DIC display.
3-58

SERVICE STABILITY
If you ever see the SERVICE STABILITY message, it
means there may be a problem with your
Stabilitrak
žsystem. If you see this message try to reset
the system (stop; turn off the engine; then start the
engine again). If the SERVICE STABILITY message still
comes on, it means there is a problem. You should
see your dealer for service. The vehicle is safe to drive,
however, you do not have the bene®t of Stabilitrak
ž,
so reduce your speed and drive accordingly.
STABILITY SYS DISABLED
The STABILITY SYS DISABLED message will turn on
when you press the Stabilitrakžbutton, or when the
stability control has been automatically disabled. To limit
wheel spin and realize the full bene®ts of the stability
enhancement system, you should normally leave
Stabilitrak
žon. However, you should turn Stabilitrakžoff
if your vehicle gets stuck in sand, mud, ice or snow
and you want to ªrockº your vehicle to attempt to free it,
or if you are driving in extreme off-road conditions
and require more wheel spin. See
If You Are Stuck: In
Sand, Mud, Ice or Snow on page 4-45.To turn the Stabilitrak
žsystem back on, press the
Stabilitrakžbutton again. There are four conditions that
can cause this message to appear. One condition is
overheating, which could occur if Stabilitrak
žactivates
continuously for an extended period of time. The
message will also be displayed if the brake system
warning light is on. See
Brake System Warning Light on
page 3-37. The message could be displayed if the
stability system takes longer than usual to complete its
diagnostic checks due to driving conditions. Also, if
an engine or vehicle related problem has been detected,
and the vehicle needs service, the message will
appear.
The message will turn off as soon as the conditions that
caused the message to be displayed are no longer
present.
TRACTION ACTIVE
When the traction control system has detected that any
of the vehicle's wheels are slipping, the traction
control system will activate and this message will appear
on the DIC. For more information see
Traction Assist
System (TAS) on page 4-10andStabilitrakžSystem
on page 4-12.
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If you decide you can go down a hill safely, then try to
keep your vehicle headed straight down, and use a
low gear. This way, engine drag can help your brakes
and they won't have to do all the work. Descend slowly,
keeping your vehicle under control at all times.
{CAUTION:
Heavy braking when going down a hill can
cause your brakes to overheat and fade. This
could cause loss of control and a serious
accident. Apply the brakes lightly when
descending a hill and use a low gear to keep
vehicle speed under control.
Q:Are there some things I should not do when
driving down a hill?
A:Yes! These are important because if you ignore
them you could lose control and have a serious
accident.
·When driving downhill, avoid turns that take you
across the incline of the hill. A hill that's not too
steep to drive down may be too steep to drive
across. You could roll over if you don't drive straight
down.
·Never go downhill with the transmission in
NEUTRAL (N). This is called ªfree-wheeling.º Your
brakes will have to do all the work and could
overheat and fade.
Q:Am I likely to stall when going downhill?
A:It's much more likely to happen going uphill. But if
it happens going downhill, here's what to do.
·Stop your vehicle by applying the regular brakes.
Apply the parking brake.
·Shift to PARK (P) and, while still braking, restart the
engine.
·Shift back to a low gear, release the parking brake,
and drive straight down.
·If the engine won't start, get out and get help.
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