2004 CHEVROLET ASTRO CARGO VAN heater

Notice:If you use an improper coolant mixture,
your engine could overheat and be badly damaged.
The repair cost would not be covered by your
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core and
other parts.
If you have to add coolant more than four times a year,
have your dealer check your cooling system.
Notice:If you use the proper coolant, you do not
have to add extra inhibitors or additives which claim
to improve the system. These can be harmful.Checking Coolant
The engine coolant
recovery tank is located in
the engine compartment
on the passenger’s side
of the vehicle. SeeEngine
Compartment Overview
on page 5-12for more
information on location.
The vehicle must be on a level surface. When your
engine is cold, the coolant level should be at ADD
or a little higher. When your engine is warm, the level
should be up to FULL HOT or a little higher.
5-27

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. See “Driving on Grades” under
Towing a Trailer on page 4-35.
If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. In heavy traffic, let the engine idle in NEUTRAL (N)
while stopped. If it is safe to do so, pull off the road,
shift to PARK (P) or NEUTRAL (N) and let the
engine idle.
2. Turn on your heater to full hot at the highest fan
speed and open the window as necessary.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 and you have not stopped,
pull over, stop, and park your vehicle right away.
If there is still no sign of steam, you can push down
the accelerator until the engine speed is about twice
as fast as normal idle speed for at least 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.
You may decide not to lift the hood but to get service
help right away.
5-30

The coolant level should be at the ADD mark. If it is
not, you may have a leak at the pressure cap or in the
radiator hoses, heater hoses, radiator, water pump
or somewhere else in the cooling system.
{CAUTION:
Heater and radiator hoses, and other engine
parts, can be very hot. Do not touch them.
If you do, you can be burned.
Do not run the engine if there is a leak.
If you run the engine, it could lose all coolant.
That could cause an engine re, and you
could be burned. Get any leak xed before
you drive the vehicle.If there seems to be no leak, start the engine again.
The engine cooling fan speed should increase when
idle speed is doubled by pushing the accelerator pedal
down. If it does not, your vehicle needs service.
Turn off the engine.
Notice:Engine damage from running your engine
without coolant is not covered by your warranty.
Notice:Using coolant other than DEX-COOL®may
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
5-32

How to Add Coolant to the Coolant
Recovery Tank
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle’s coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you would not get the overheat warning.
Your engine could catch re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.
Notice:In cold weather, water can freeze and crack
the engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mixture.If you have not found a problem yet, but the coolant
level is not at the ADD mark, add a 50/50 mixture
ofclean, drinkable waterand DEX-COOL
®engine
coolant at the coolant recovery tank. SeeEngine
Coolant on page 5-26for more information.
{CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol
and it will burn if the engine parts are hot
enough. Do not spill coolant on a hot engine.
5-33

Relays Usage
A/C Relay
(Rear Heat
and A/C)Rear/Heat and Air Conditioning
Uptter-ACCY
RelayUptter Accessory
Starter Enable
RelayStarter
A/C Enable
RelayAir Conditioning
Headlamps
RelayHeadlamps
Fuel Pump
RelayFuel PumpFuse/Circuit
BreakerUsage
UPFITTER-
BATTUptter Battery Power Stud,
Trailer Wiring Harness
UPFITTER-
ACCYUptter Accessory Relay
Spare Not used
Spare Not used
Spare Not used
ECM-1BFuel Pump Relay and Motor,
VCM, Oil Pressure Switch/Sender
HORN Horn Relay and Horn
A/C COMPAir Conditioning Enable Relay
and Compressor
RR HTR/AC Rear Heater and Air Conditioning
ATC Active Transfer Case-L Van
FRT HVAC Front Heater and Air Conditioning
5-105

Capacities and Specications
The following approximate capacities are given in English and metric conversions. Please refer to
Part D: Recommended Fluids and Lubricants on page 6-28for more information.
Capacities and Specications
ApplicationCapacities
English Metric
Air Conditioning Refrigerant (R134a)
Front A/C
Front and Rear A/C2.3 lbs.
3.0 lbs.1.0 kg
1.4 kg
Cooling System
Without Rear Heater
With Rear Heater13.5 quarts
16.5 quarts12.8 L
15.6 L
Differential Fluid
Front Axle
Rear Axle2.6 pints
3.5 pints1.2 L
1.7 L
Engine Oil with Filter 4.5 quarts 4.3 L
Fuel Tank 27.0 gallons 101.8 L
5-107

Chains, Tire...................................................5-76
Charging System Light....................................3-26
Check
Engine Light...............................................3-29
Gages Warning Light...................................3-34
Checking Brake Fluid......................................5-41
Checking Coolant............................................5-27
Checking Engine Oil........................................5-13
Checking Things Under the Hood....................... 5-9
Chemical Paint Spotting...................................5-97
Child Restraints
Child Restraint Systems...............................1-43
Infants and Young Children...........................1-38
Lower Anchorages and Top Tethers for
Children (LATCH System)..........................1-51
Older Children.............................................1-35
Securing a Child Restraint Designed for
the LATCH System...................................1-54
Securing a Child Restraint in a Center
Seat Position...........................................1-56
Securing a Child Restraint in a Rear
Outside Seat Position...............................1-54
Securing a Child Restraint in the Right
Front Seat Position...................................1-58
Top Strap...................................................1-47
Top Strap Anchor Location............................1-49
Where to Put the Restraint...........................1-46
Cigarette Lighter.............................................3-16Cleaning
Inside of Your Vehicle..................................5-92
Outside of Your Vehicle................................5-95
Underbody Maintenance...............................5-97
Weatherstrips..............................................5-94
Cleaning Aluminum Wheels..............................5-96
Cleaning Exterior Lamps/Lenses.......................5-95
Cleaning Fabric/Carpet....................................5-92
Cleaning Glass Surfaces..................................5-94
Cleaning Interior Plastic Components.................5-94
Cleaning Leather............................................5-93
Cleaning the Top of the Instrument Panel...........5-93
Cleaning the Windshield and
Wiper Blades..............................................5-96
Cleaning Tires................................................5-97
Cleaning Vinyl................................................5-93
Climate Control System...................................3-17
Outlet Adjustment........................................3-19
Rear Air Conditioning System........................3-20
Rear Heating System...................................3-20
Compact Spare Tire........................................5-90
Composite Headlamps.....................................5-54
Control of a Vehicle.......................................... 4-5
Convenience Net............................................2-43
Coolant
Engine Temperature Gage............................3-28
Heater, Engine............................................2-21
Cooling System..............................................5-31
3

E
Electrical System
Add-On Equipment.....................................5-100
Fuses and Circuit Breakers.........................5-101
Headlamp Wiring.......................................5-100
Power Windows and Other Power Options....5-100
Windshield Wiper Fuses.............................5-100
Emissions Inspection and Maintenance
Programs...................................................3-31
Engine
Air Cleaner/Filter.........................................5-21
Battery.......................................................5-44
Check and Service Engine Soon Light............3-29
Coolant......................................................5-26
Coolant Heater............................................2-21
Coolant Temperature Gage...........................3-28
Cooling System Inspection............................6-26
Cover........................................................5-17
Drive Belt Routing......................................5-110
Engine Compartment Overview......................5-12
Exhaust.....................................................2-29
Fan Noise..................................................5-37
Oil .............................................................5-13
Overheating................................................5-29
Starting......................................................2-20
Engine Coolant Level Check.............................6-22Engine Oil Additives........................................5-16
Engine Oil Level Check...................................6-22
Entry Lighting.................................................3-14
Erasing HomeLink®Buttons..............................2-35
Event Data Recorders (EDR)............................7-10
Except Cargo Vans.................................1-38, 1-46
Exit Lighting...................................................3-14
Express-Down Window....................................2-16
Extender, Safety Belt.......................................1-34
Exterior Lamps...............................................3-12
F
Filter
Engine Air Cleaner......................................5-21
Finding a Station....................................3-37, 3-39
Finish Care....................................................5-95
Finish Damage...............................................5-97
Fixed Mast Antenna........................................3-47
Flash-to-Pass................................................... 3-7
Flat Tire........................................................5-77
Flat Tire, Changing.........................................5-78
Fluid
Automatic Transmission................................5-23
Power Steering...........................................5-38
Windshield Washer......................................5-39
5