2004 CHEVROLET ASTRO heater

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. See²Driving on Gradesº inTowing 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 doesn't 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's 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're parked. If you still have the warning,
turn off the
engine and get everyone out of the vehicleuntil it
cools down.
You may decide not to lift the hood but to get service
help right away.
5-29

Cooling System
When you decide it's safe to lift the hood, here's what
you'll see:
A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Engine Cooling FanIf the coolant inside the coolant recovery tank is boiling,
don't do anything else until it cools down. The vehicle
should be parked on a level surface.
The coolant level should
be at the ADD mark.
If it isn't, 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.
5-30

{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 doesn't, 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-COOLžmay
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
ž(silicate-free) coolant in your vehicle.
5-31

How to Add Coolant to the Coolant
Recovery Tank
If you haven't found a problem yet, but the coolant level
isn't at the ADD mark, add a 50/50 mixture ofclean
drinkable water, and DEX-COOLžengine coolant at the
coolant recovery tank. SeeEngine Coolant on
page 5-25for more information.
{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
žcoolant.
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.
{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.
5-32

Fuse/Circuit
BreakerUsage
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
ENG-IOxygen Sensors, Camshaft Position
Sensor, Mass Air Flow Sensor,
Evaporative Emission Canister Vent
Solenoid
IGN-E Air Conditioning Enable Relay Coil
ECM-IFuel Injectors 1±6, Crankshaft
Position Sensot, VCM, Coil Driver
Module (EST), Ignition Coil
Blank Not Used
RH HDLMP Right Headlamp
LH Headlamp Left Headlamp
Blank Not Used
Blank Not UsedFuse/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 Fuse
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
5-101

Capacities and Speci®cations
ApplicationCapacities
English Metric
Cooling Capacities
Quantity without Rear Heater
Quantity with Rear Heater13.5 quarts
16.5 quarts12.8 L
15.6 L
Engine Oil with Filter 4.5 quarts 4.3 L
Fuel Tank 27.0 gallons 101.8 L
Transmission Fluid (Drain and Re®ll) 5.0 quarts 4.7 L
Differential Fluid
Front Axle
Rear Axle2.6 pints
3.5 pints1.2 L
1.7 L
Refrigerant Type 134a
Front A/C
Front and Rear A/C2.25 lbs.
3.0 lbs.1.02 kg
1.36 kg
All capacities are approximate. When adding, be sure to ®ll to the appropriate level, as recommended in this
manual. recheck the ¯uid level after ®lling. See
Part D: Recommended Fluids and Lubricants on page 6-30for
more information.
5-103

Cleaning Leather............................................5-88
Cleaning the Top of the Instrument Panel...........5-89
Cleaning the Windshield and
Wiper Blades..............................................5-91
Cleaning Tires................................................5-92
Cleaning Vinyl................................................5-88
Climate Control System...................................3-18
Outlet Adjustment........................................3-20
Rear Air Conditioning System........................3-21
Rear Heating System...................................3-21
Compact Spare Tire........................................5-86
Composite Headlamps.....................................5-51
Control of a Vehicle.......................................... 4-6
Convenience Net............................................2-41
Coolant
Engine Temperature Gage............................3-30
Heater, Engine............................................2-20
Cooling System..............................................5-30
Cruise Control................................................3-10
Current and Past Model Order Forms................7-12
Customer Assistance Information
Courtesy Transportation.................................. 7-7
Customer Assistance for Text Telephone
(TTY) Users.............................................. 7-4
Customer Assistance Offices........................... 7-4
Customer Satisfaction Procedure..................... 7-2Customer Assistance Information (cont.)
GM Mobility Program for Persons with
Disabilities................................................ 7-5
Reporting Safety Defects to
General Motors........................................7-11
Reporting Safety Defects to the Canadian
Government............................................7-11
Reporting Safety Defects to the United
States Government...................................7-10
Roadside Assistance Program......................... 7-6
Service Publications Ordering Information........7-11
D
Daytime Running Lamps (DRL).........................3-14
Defensive Driving............................................. 4-2
Defogging and Defrosting.................................3-19
Directing the Air¯ow........................................3-22
Disabling the Theft-Deterrent Feature.................3-49
Doing Your Own Service Work........................... 5-3
Dome Lamps.................................................3-16
Door
Locks.......................................................... 2-6
Power Door Locks......................................... 2-7
Programmable Automatic Door Locks............... 2-7
Rear Doors.................................................2-11
Sliding Side Door.......................................... 2-9
4

Driver
Position, Safety Belt.....................................1-18
Driver Information System................................2-38
Driving
At Night.....................................................4-14
City...........................................................4-19
Defensive..................................................... 4-2
Drunken....................................................... 4-3
Freeway.....................................................4-20
Hill and Mountain Roads..............................4-22
In Rain and on Wet Roads...........................4-16
Winter........................................................4-24
Driving On Grades..........................................4-42
Driving on Snow or Ice....................................4-25
Driving Through Deep Standing Water...............4-18
Driving Through Flowing Water.........................4-18
Driving with a Trailer.......................................4-41
E
Electrical System
Add-On Equipment......................................5-95
Fuses and Circuit Breakers...........................5-96
Headlamp Wiring.........................................5-96
Power Windows and Other Power Options......5-96
Windshield Wiper Fuses...............................5-96
Emissions Inspection and Maintenance
Programs...................................................3-33Engine
Air Cleaner/Filter.........................................5-21
Battery.......................................................5-42
Check and Service Engine Soon Light............3-30
Coolant......................................................5-25
Coolant Heater............................................2-20
Coolant Temperature Gage...........................3-30
Cooling System Inspection............................6-28
Cover........................................................5-17
Drive Belt Routing......................................5-105
Engine Compartment Overview......................5-12
Exhaust.....................................................2-28
Fan Noise..................................................5-36
Oil .............................................................5-13
Overheating................................................5-28
Starting......................................................2-19
Engine Coolant Level Check.............................6-24
Engine Oil Additives........................................5-16
Engine Oil Level Check...................................6-24
Entry Lighting.................................................3-15
Erasing HomeLinkžButtons..............................2-33
Event Data Records (EDR)................................ 7-9
Except Cargo Vans.................................1-38, 1-47
Exit Lighting...................................................3-15
Express-Down Window....................................2-15
Extender, Safety Belt.......................................1-34
Exterior Lamps...............................................3-12
5