2003 CHEVROLET ASTRO air condition

California Fuel Additives
If your vehicle is certified to meet California Emission
Standards (see the underhood emission control label),
it is designed to operate on fuels that meet California
specifications.
If this fuel is not available in states
adopting California emissions standards, your vehicle
will operate satisfactorily on fuels meeting federal
specifications, but emission control system performance
may be affected. The malfunction indicator lamp may
turn on (see
Malfunction Indicator Lamp on page 3-30 )
and your vehicle may fail a smog-check test. If this
occurs, return to your authorized GM dealer for
diagnosis. If it is determined that the condition is caused
by the type of fuel used, repairs may not be covered
by your warranty.
To provide cleaner air, all gasolines in the United States
are now required to contain additives that will help
prevent engine and fuel system deposits from forming,
allowing your emission control system to work
properly. You should not have
to add anything to
your fuel. Gasolines containing oxygenates, such as
ethers and ethanol, and reformulated gasolines
may be available in your area to contribute to clean air.
General Motors recommends that you use these
gasolines, particularly
if they comply with the
specifications described earlier.
Notice: Your vehicle was not designed for fuel
that contains methanol. Don’t use fuel containing
methanol. It can corrode metal parts in your fuel
system and also damage the plastic and rubber
parts. That damage wouldn’t be covered under
your warranty.
5-6

6. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fan.
7. By this time, the coolant level inside the radiator
filler neck may be lower.
If the level is lower, add
more of the proper
DEX-COOL@ coolant mixture
through the filler neck until the level reaches
the base of the filler neck.
Then replace the pressure cap. At any time during
this procedure
if coolant begins to flow out of
the filler neck, reinstall the pressure cap. Be sure
the arrow on the pressure cap lines up.
Engine Fan Noise
This vehicle has a clutched engine cooling fan. When
the clutch is engaged, the fan spins faster to provide
more air to cool the engine. In most everyday driving
conditions, the clutch is not fully engaged. This improves
fuel economy and reduces fan noise. Under heavy
vehicle loading, trailer towing and/or high outside
temperatures, the fan speed increases when the clutch
engages.
So you may hear an increase in fan noise.
This is normal and should not be mistaken as the
transmission slipping or making extra shifts. It is merely
the cooling system functioning properly. The fan will
slow down when additional cooling is not required and
the clutch disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch disengages.
5-39

Brake Wear
Your vehicle has four-wheel disc brakes,
Disc brake pads have built-in wear indicators that make
a high-pitched warning sound when the brake
pads
are worn and new pads are needed. The sound
may come and go or be heard all the time your vehicle
is moving (except when you are pushing on the
brake pedal firmly).
The brake wear warning sound means that soon
your brakes won’t work well. That could lead to
an accident. When
you hear the brake wear
Notice: Continuing to drive with worn-out brake
pads could result in costly brake repair.
Some driving conditions or climates may cause a brake
squeal when the brakes are first applied or lightly
applied. This does not mean something is wrong with
your brakes.
Properly torqued wheei nuts are necessary to heip
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in
the proper sequence to
GM torque specifications.
Brake linings should always be replaced as complete
axle sets.
See
Brake System Inspection on page 6-31.
Brake Pedal Travel
See your dealer if the brake pedal does not return to
normal height, or if there is a rapid increase in
pedal travel. This could be a sign of brake trouble.
Brake Adjustment
Every time you make a brake stop, your disc brakes
adjust for wear.
5-45

Wheel Alignment and Tire Balance If you need to replace any of your wheels, wheel bolts
or wheel nuts, replace them only with new
GM
The wheels on your vehicle were aligned and balanced original
equipment parts. This way, you will be sure to
carefully at the factory to give you the longest tire life have
the right wheel, wheel bolts and wheel nuts for
and best overall performance.
your
vehicle.
Scheduled wheel alignment and wheel balancing are
not needed. However,
if you notice unusual tire wear or
your vehicle pulling one way or the other, the alignment
may need to be reset.
If you notice your vehicle
vibrating when driving on a smooth road, your wheels
may need to be rebalanced.
Wheel Replacement
Replace any wheel that is bent, cracked or badly
rusted or corroded.
If wheel nuts keep coming loose,
the wheel, wheel bolts and wheel nuts should be
replaced. If the wheel leaks air, replace it (except some
aluminum wheels, which can sometimes be repaired).
See your dealer
if any of these conditions exist.
Your dealer will know the kind of wheel you need.
Each new wheel should have the same load-carrying
capacity, diameter, width, offset and be mounted
the same way as the one it replaces. the wrong replacement wheels, wheel
bolts or wheel nuts on your vehicle can be
dangerous.
It could affect the braking and
handling of your vehicle, make your tires lose
air and make you lose control. You could have
a collision
in which you or others could be
injured. Always use the correct wheel, wheel
bolts and wheel nuts for replacement.
Notice: The wrong wheel can also cause problems
with bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper height,
vehicle ground clearance and tire or tire chain clearance to the body and chassis.
See
Changing a Flat Tire on page 5-71 for more
information.
-~
5-69

Underbody Maintenance
Chemicals used for ice and snow removal and dust
control can collect on the underbody.
If these are not
removed, accelerated corrosion (rust} can occur on
the underbody parts such as fuel lines, frame, floor pan
and exhaust system even though they have corrosion
protection.
At least every spring, flush these materials from the
underbody with plain water. Clean any areas where mud
and debris can collect. Dirt packed in close areas of
the frame should be loosened before being flushed.
Your dealer or an underbody car washing system can
do this for you.
Chemical Paint Spotting
Some weather and atmospheric conditions can create a
chemical fallout. Airborne pollutants can fall upon and
attack painted surfaces on your vehicle. This damage can
take two forms; blotchy, ringlet-shaped discolorations,
and small irregular dark spots etched into the paint
surface.
Although no defect in the paint job causes this, GM will
repair, at no charge to the owner, the surfaces of
new vehicles damaged by this fallout condition within
12 months or 12,000 miles (20 000 km) of purchase,
whichever occurs first.
GM Vehicle Care/Appearance
Materials
See your GM dealer for more information on purchasing
the following products.
GM Vehicle Care/Appearance Materials
Descrbtion Usaae I
Polishing Cloth
Dolishina cloth.
Wax-Treated Interior and exterior
Tar and Road Oil
and asPhalt.
Remover Removes
tar, road oil
Chrome Cleaner
stainless steel.
and Polish Use on chrome or
White Sidewall
marks from whitewalls.
Tire Cleaner Removes
soil and black
Vinyl Cleaner Cleans
vinyl tops,
upholstery and
convertible tom.
Glass Cleaner Removes
dirt, grime,
smoke and finaerprints.
5-89

13
14
15
16
Fuse/Circuit Usage Breaker
10 Air Bag System
11 Not Used
12 L, MI, M2 Blower Motor, Rear Air
Conditioning Relay Coil, Front Cont.
Temp. Door Motor, HI Blower Relay.
Defogger Timer Coil
Cigarette Lighter, Door Lock
Switches, Dutch Door Release Module
Cluster Illum, Climate Controls,
Chime Module, Radio Illumination,
Rear Heat Switch Illumination, Rear
Wipermasher Switch Illumination,
Rear Liftgate Switch Illumination,
Remote Cassette Illumination,
Overhead Console, Truck Body
Control Illurnination
Truck Body Module, Headlamp Relay
Front Turn Signals, Rear Turn
Signals, Trailer Turn Signals,
Back-up Lamps, Brake Transmission
Shift Interlock Solenoid 21
22
23
24
A
19
20
FuseKircuit
Usage
Breaker
17 Front Wipers, Front Washer Pump
18 VCM-lgn
3, VCM-Brake, Cruise
Stepper Motor Signal, ATC Module
Instrument Panel Radio: ATC
(Main Feed),
2000 Series (Standby)
PRNDUOdometer, TCC Enable and
PWM Solenoid, Shift A and Shift B
Solenoids, 3-2 Downshift Solenoid, Instrument Panel Cluster, VCM
Module
Powr Adjust Mirrors
Not Used
Rear Wiper, Rear Washer Pump
Not Used
(Circuit Breaker) Power Door Lock
Relay, 6-Way Power Seats
(Circuit Breaker) Power Windows
B
5-95

Usage
Rear/Heat and Air Conditioning
Relays
AIC Relay
(Rear Heat
and AIC)
Relay
Relay
A/C Enable
Relay
Upfitter-ACCY
Upfitter Accessory
Starter Enable Starter
Headlamps Relay
Fuel Pump
Relay Air
Conditioning
Headlamps
Fuel Pump
FuselCircuit
Usage
UPFITTER- Upfitter Battery Power Stud,
BATT Trailer Wiring Harness
UPFITTER- Upfitter Accessory Relay
ACCY
Spare Not used
Spare Not used
Breaker FuselCircuit
Breaker
Spare
ECM-1 B
HORN
AIC COMP
RR HTR/AC ATC
FRT HVAC
ENG-I
IGN-E
ECM-I
Blank
RH HDLMP
LH Headlamp
Blank
Blank
Usage
Not used
Fuel Pump Relay and Motor, VCM,
Oil Pressure Switch/Sender
Horn Relay and Horn
Air Conditioning Enable Relay and
Compressor
Rear Heater and Air Conditioning
Active Transfer Case-L Van
Front Heater and Air Conditioning
Oxygen Sensors, Camshaft Position
Sensor, Mass Air Flow Sensor,
Evaporative Emission Canister
Vent Solenoid
Air Conditioning Enable Relay Coil
Fuel Injectors
1-6, Crankshaft
Position Sensot, VCM, Coil Driver
Module (EST), Ignition Coil
Not Used
Right Headlamp
Left Headlamp
Not Used
Not Used
5-97

Fuse/Circuit Usage
Breaker
DIODE-I Air Conditioning
Blank Not Used
Blank
Not Used
Blank Not Used
LIGHTING Courtesy Fuse, Power Adjust
Mirrors Fuse, Truck Body Control
Battery Fuse
Power Accessory Circuit Breaker,
Stop/Hazard Fuse, Auxiliary Power
Fuse, Cigarette Lighter Fuse, Radio
Battery Fuse
BATT
Fuse/Circuit
Breaker
IGN A
IGN
B
ABS
Blank RAP
HTD MIRI
RR DEFOG
Usage
Starter Relay, Ignition Switch
Ignition Switch
Electronic Brake Control Module
Not Used Radio Accessory, Power Windows
Rear Window Defogger,
Climate Control Head
5-98