2003 CHEVROLET ASTRO CARGO VAN brake

Fuse/Circuit
BreakerUsage
1Stop/Turn/Hazard Lamps, Center
High Mounted Stop Lamp, Anti-Lock
Brakes
2Radio Accy, Rear Seat Audio
ControlsFuse/Circuit
BreakerUsage
3Courtesy Lamps, Glove Box Lamp,
Dome Reading Lamps, Vanity Mirror
Lamps, Courtesy Lamps
4Daytime Running Lamps Relay,
Instrument Panel Cluster
5 Rear Defogger
6Cruise Module, Truck Body Control
Module, Instrument Panel Cluster,
Cruise Control Switch,
Electrochromic Mirror
7Power Outlets, DLC, Subwoofer
Ampli®er
8Crank Circuit Fuse, Park/Neutral
Switch, Starter Enabler Relay
9License Plate Lamp, Tailamps,
Parking Lamps, Ashtray Lamp,
Panel Lights, Trailer Taillamps, Front
and Rear Sidemarker Lamps, Door
Switch Illumination, Headlamp
Switch Illumination, Rear Seat Audio
Illumination, Truck Body
Control Module
5-94

Fuse/Circuit
BreakerUsage
10 Air Bag System
11 Not Used
12L, M1, M2 Blower Motor, Rear Air
Conditioning Relay Coil, Front Cont.
Temp. Door Motor, HI Blower Relay,
Defogger Timer Coil
13Cigarette Lighter, Door Lock
Switches, Dutch Door Release
Module
14Cluster Illum, Climate Controls,
Chime Module, Radio Illumination,
Rear Heat Switch Illumination, Rear
Wiper/Washer Switch Illumination,
Rear Liftgate Switch Illumination,
Remote Cassette Illumination,
Overhead Console, Truck Body
Control Illumination
15Truck Body Module, Headlamp
Relay
16Front Turn Signals, Rear Turn
Signals, Trailer Turn Signals,
Back-Up Lamps, Brake
Transmission Shift Interlock SolenoidFuse/Circuit
BreakerUsage
17 Front Wipers, Front Washer Pump
18VCM-Ign 3, VCM-Brake, Cruise
Stepper Motor Signal, ATC Module
19Instrument Panel Radio: ATC (Main
Feed), 2000 Series (Standby)
20PRNDL/Odometer, TCC Enable and
PWM Solenoid, Shift A and Shift B
Solenoids, 3±2 Downshift Solenoid,
Instrument Panel Cluster, VCM
Module
21 Powr Adjust Mirrors
22 Not Used
23 Rear Wiper, Rear Washer Pump
24 Not Used
A(Circuit Breaker) Power Door Lock
Relay, 6±Way Power Seats
B (Circuit Breaker) Power Windows
5-95

Fuse/Circuit
BreakerUsage
DIODE-1 Air Conditioning
Blank Not Used
Blank Not Used
Blank Not Used
LIGHTINGCourtesy Fuse, Power Adjust Mirrors
Fuse, Truck Body Control Battery
Fuse
BATTPower Accessory Circuit Breaker,
Stop/Hazard Fuse, Auxiliary Power
Fuse, Cigarette Lighter Fuse, Radio
Battery FuseFuse/Circuit
BreakerUsage
IGN A Starter Relay, Ignition Switch
IGN B Ignition Switch
ABSElectronic Brake
Control Module
Blank Not Used
RAP Radio Accessory, Power Windows
HTD MIR/RR
DEFOGRear Window Defogger,Climate
Control Head
5-98

Maintenance Schedule......................................6-2
Introduction...................................................6-2
Your Vehicle and the Environment....................6-2
Maintenance Requirements..............................6-2
How This Section is Organized.........................6-3
Part A: Scheduled Maintenance Services...........6-4
Using Your Maintenance Schedule....................6-4
Selecting the Right Schedule...........................6-5
Short Trip/City Scheduled Maintenance..............6-7
Long Trip/Highway Scheduled Maintenance......6-18
Part B: Owner Checks and Services................6-26
At Each Fuel Fill..........................................6-26
At Least Once a Month.................................6-26
At Least Twice a Year...................................6-26At Least Once a Year...................................6-27
Part C: Periodic MaintenanceInspections...........6-30
Steering, Suspension and Front Drive Axle
Boot and Seal Inspection............................6-30
Exhaust System Inspection............................6-30
Fuel System Inspection..................................6-30
Engine Cooling System Inspection...................6-30
Throttle System Inspection.............................6-31
Transfer Case and Front Axle
(All-Wheel Drive) Inspection........................6-31
Brake System Inspection................................6-31
Part D: Recommended Fluids and Lubricants......6-32
Part E: Maintenance Record...........................6-34
Section 6 Maintenance Schedule
6-1

Selecting the Right Schedule
First you'll need to decide which of the two schedules is
right for your vehicle. Here's how to decide which
schedule to follow:
Short Trip/City De®nition
Follow the Short Trip/City Scheduled Maintenance if any
one of these conditions is true for your vehicle:
·Most trips are less than 5 miles (8 km). This is
particularly important when outside temperatures
are below freezing.
·Most trips include extensive idling (such as frequent
driving in stop-and-go traffic).
·You frequently tow a trailer or use a carrier on top
of your vehicle.
·If the vehicle is used for delivery service, police,
taxi or other commercial application.
One of the reasons you should follow this schedule if
you operate your vehicle under any of these conditions
is that these conditions cause engine oil to break
down sooner.
Short Trip/City Intervals
Every 3,000 Miles (5 000 km):Engine Oil and Filter
Change (or 3 months, whichever occurs ®rst). Chassis
Lubrication (or 3 months, whichever occurs ®rst).
Drive Axle Fluid Check.
Every 6,000 Miles (10 000 km):Tire Rotation.
Every 15,000 Miles (25 000 km):Engine Air Cleaner
Filter Inspection. Front Wheel Bearing Repack
(two±wheel drive only) (or at each brake relining,
whichever occurs ®rst). Automatic Transmission Service
(severe conditions only).
Every 30,000 Miles (50 000 km):Engine Air Cleaner
Filter Replacement. Fuel Filter Replacement.
Every 50,000 Miles (83 000 km):Automatic
Transmission Service (normal conditions). Transfer
Case Fluid Change.
Every 100,000 Miles (166 000 km):Spark Plug Wire
Inspection. Spark Plug Replacement. Positive
Crankcase Ventilation (PCV) Valve Inspection.
Every 150 000 Miles (240 000 km):Cooling System
Service (or every 60 months, whichever occurs
®rst). Engine Accessory Drive Belt Inspection.
These intervals only summarize maintenance services.
Be sure to follow the complete scheduled maintenance
on the following pages.
6-5

Long Trip/Highway De®nition
Follow this scheduled maintenanceonlyif none of the
conditions from the Short Trip/City Scheduled
Maintenance are true. Do not use this schedule if the
vehicle is used for trailer towing, driven in a dusty area
or used off paved roads. Use the Short Trip/City
schedule for these conditions
Driving a vehicle with a fully warmed engine under
highway conditions will cause engine oil to break down
slower.
Long Trip/Highway Intervals
Every 7,500 Miles (12 500 km):Engine Oil and Filter
Change (or every 12 months, whichever occurs ®rst).
Chassis Lubrication (or 12 months, whichever occurs
®rst). Drive Axle Fluid Check. Tire Rotation.
Every 15,000 Miles (25 000 km):Engine Air Cleaner
Filter Inspection. Automatic Transmission Service
(severe conditions only).Every 30,000 Miles (50 000 km):Fuel Filter
Replacement. Engine Air Cleaner Filter Replacement.
Front Wheel Bearing Repack (two±wheel drive only)
(or at each brake relining, whichever occurs ®rst).
Every 50,000 Miles (83 000 km):Automatic
Transmission Service (normal conditions). Transfer
Case Fluid Change.
Every 100,000 Miles (166 000 km):Spark Plug Wire
Inspection. Spark Plug Replacement. Positive
Crankcase Ventilation (PCV) Valve Inspection.
Every 150,000 Miles (240 000 km):Cooling System
Service (or every 60 months, whichever occurs
®rst). Engine Accessory Drive Belt Inspection.
These intervals only summarize maintenance services.
Be sure to follow the complete scheduled maintenance
on the following pages.
6-6

Short Trip/City Scheduled
Maintenance
The services shown in this schedule up to 100,000 miles
(166 000 km) should be repeated after 100,000 miles
(166 000 km) at the same intervals for the life of this
vehicle. The services shown at 150,000 miles
(240 000 km) should be repeated at the same interval
after 150,000 miles (240 000 km) for the life of this
vehicle.
See
Part B: Owner Checks and Services on page 6-26andPart C: Periodic MaintenanceInspections on
page 6-30.
Footnotes
²The U.S. Environmental Protection Agency or the
California Air Resources Board has determined that the
failure to perform this maintenance item will not nullify
the emission warranty or limit recall liability prior to
the completion of the vehicle's useful life. We, however,
urge that all recommended maintenance services be
performed at the indicated intervals and the
maintenance be recorded.
#Lubricate the front suspension, ball joints and kingpin
bushings, steering linkage, parking brake cable
guides and brake pedal springs.
+A good time to check your brakes is during tire
rotation. See Brake System Inspection on page 6-31.
3,000 Miles (5 000 km)
qChange engine oil and ®lter (or every 3 months,
whichever occurs ®rst).An Emission Control Service.
qLubricate chassis components (or every 3 months,
whichever occurs ®rst).(See footnote #.)
qCheck rear/front axle ¯uid level and add ¯uid as
needed. Check constant velocity joints and axle seals
for leaking.
6,000 Miles (10 000 km)
qChange engine oil and ®lter (or every 3 months,
whichever occurs ®rst).An Emission Control Service.
qLubricate chassis components (or every 3 months,
whichever occurs ®rst).(See footnote #.)
qCheck rear/front axle ¯uid level and add ¯uid as
needed. Check constant velocity joints and axle seals
for leaking.
qRotate tires. See
Tire Inspection and Rotation on
page 5-64for proper rotation pattern and additional
information.(See footnote +.)
9,000 Miles (15 000 km)
qChange engine oil and ®lter (or every 3 months,
whichever occurs ®rst).An Emission Control Service.
qLubricate chassis components (or every 3 months,
whichever occurs ®rst).(See footnote #.)
qCheck rear/front axle ¯uid level and add ¯uid as
needed. Check constant velocity joints and axle seals
for leaking.
6-7

12,000 Miles (20 000 km)
qChange engine oil and ®lter (or every 3 months,
whichever occurs ®rst).An Emission Control Service.
qLubricate chassis components (or every 3 months,
whichever occurs ®rst).(See footnote #.)
qCheck rear/front axle ¯uid level and add ¯uid as
needed. Check constant velocity joints and axle seals
for leaking.
qRotate tires. See
Tire Inspection and Rotation on
page 5-64for proper rotation pattern and additional
information.(See footnote +.)
15,000 Miles (25 000 km)
qChange engine oil and ®lter (or every 3 months,
whichever occurs ®rst).An Emission Control Service.
qLubricate chassis components (or every 3 months,
whichever occurs ®rst).(See footnote #.)
qInspect engine air cleaner ®lter. If necessary, replace
the ®lter. If vehicle is driven in dusty/dirty conditions,
inspect ®lter at every engine oil change. See
Engine
Air Cleaner/Filter on page 5-24for more information.An Emission Control Service. (See footnote ².)
qCheck rear/front axle ¯uid level and add ¯uid as
needed. Check constant velocity joints and axle seals
for leaking.qFor Two-Wheel-Drive vehicles only: Clean and repack
the front wheel bearings (or at each brake relining,
whichever occurs ®rst).
qChange automatic transmission ¯uid and ®lter if the
vehicle is mainly driven under one or more of these
conditions:
þ In heavy city traffic where the outside
temperature regularly reaches 90ÉF (32ÉC)
or higher.
þ In hilly or mountainous terrain.
þ When doing frequent trailer towing.
þ Uses such as found in taxi, police or delivery
service.
If you do not use your vehicle under any of these
conditions, change the ¯uid and ®lter every 50,000 miles
(83 000 km).
18,000 Miles (30 000 km)
qChange engine oil and ®lter (or every 3 months,
whichever occurs ®rst).An Emission Control Service.
qLubricate chassis components (or every 3 months,
whichever occurs ®rst).(See footnote #.)
qCheck rear/front axle ¯uid level and add ¯uid as
needed. Check constant velocity joints and axle seals
for leaking.
qRotate tires. See
Tire Inspection and Rotation on
page 5-64for proper rotation pattern and additional
information.(See footnote +.)
6-8