wiring CHEVROLET ASTRO 2004 Owners Manual

To close the rear doors, close the driver's side door
®rst. Check to make sure both doors are completely
closed.
The rear doors have a check assembly to keep the
doors from opening beyond 90 degrees.
To fully open the rear
doors, push in on the clip
and lift the check
assembly up off the
mounting bracket.
Do this on each door. Replace the check assemblies on
the mounting brackets before closing the doors.
{CAUTION:
It can be dangerous to drive with the rear
glass open because carbon monoxide (CO)
gas can come into your vehicle. You can not
see or smell CO. It can cause
unconsciousness and even death. If you must
drive with the rear glass open or if electrical
wiring or other cable connections must pass
through the seal between the body and the
rear glass:
·Make sure all other windows are shut.
·Turn the fan on your heating or cooling
system to its highest speed and select the
control setting that will force outside air
into your vehicle. See
Climate Control
System on page 3-16.
·If you have air outlets on or under the
instrument panel, open them all the way.
See
Engine Exhaust on page 2-28.
2-12

If a bulb is burned out, replace it to help avoid an
accident. If the arrows don't go on at all when you signal
a turn, check for burned-out bulbs and a blown fuse.
See
Fuses and Circuit Breakers on page 5-89.
If you have a trailer towing option with added wiring for
the trailer lamps, a different turn signal ¯asher is
used. With this ¯asher installed, the signal indicator will
¯ash even if a turn signal bulb is burned out. Check
the front and rear turn signal lamps regularly to make
sure they are working.
Turn Signal On Chime
If your turn signal is left on for more than 3/4 of a mile
(1.2 km), a chime will sound at each ¯ash of the
turn signal. To turn off the chime, move the turn signal
lever to the center position.
Headlamp High/Low-Beam Changer
To change the headlamps from low beam to high or high
to low, pull the multifunction lever all the way toward
you. Then release it.
When the high beams are
on, this indicator light
located on the instrument
panel cluster also will
be on.
Flash-to-Pass
This feature lets you use your high-beam headlamps to
signal a driver in front of you that you want to pass.
It works even if your headlamps are in automatic.
To use it, pull the turn signal lever toward you, but not
so far that you hear a click.
If your headlamps are in automatic or on low beam,
your high-beam headlamps will turn on. They'll stay on
as long as you hold the lever toward you and the
high-beam indicator located on the cluster comes on.
Release the lever to return to normal operation.
3-7

Safety Belt Reminder Light
When the key is turned to RUN or START, a tone will
come on for several seconds to remind people to fasten
their safety belts, unless the driver's safety belt is
already buckled.
The safety belt light will
also come on and stay on
for several seconds,
then it will ¯ash for
several more.
If the driver's belt is already buckled, neither the tone
nor the light will come on.
Air Bag Readiness Light
There is an air bag readiness light on the instrument
panel, which shows AIR BAG or the air bag symbol. The
system checks the air bag's electrical system for
malfunctions. The light tells you if there is an electrical
problem. The system check includes the air bag
sensor, the air bag modules, the wiring and the crash
sensing and diagnostic module. For more information on
the air bag system, see
Air Bag System on page 1-58.
This light will come on when you start your vehicle, and
it will ¯ash for a few seconds. Then the light should
go out. This means the system is ready.
United StatesCanada
3-26

If you'll be pulling a trailer that, when loaded, will weigh
more than 2,000 lbs. (900 kg.), be sure to use a
properly mounted, weight-distributing hitch and sway
control of the proper size. This equipment is very
important for proper vehicle loading and good handling
when you're driving. You should always use a sway
control if your trailer will weigh more than these limits.
You can ask a hitch dealer about sway controls.
Will you have to make any holes in the body of your
vehicle when you install a trailer hitch?
If you're using the wiring provided with the
factory-installed trailering package, you should not need
to make any holes in the body of your vehicle.
However, if you have an aftermarket hitch installed, you
may need to make holes in the body.
If you do, then be sure to seal the holes later when you
remove the hitch. If you don't seal them, deadly
carbon monoxide (CO) from your exhaust can get into
your vehicle as well as dirt and water. See ªCarbon
Monoxideº under
Engine Exhaust on page 2-26.
Safety Chains
You should always attach chains between your vehicle
and your trailer. Cross the safety chains under the tongue
of the trailer to help prevent the tongue from contacting
the road if it becomes separated from the hitch.
Instructions about safety chains may be provided by the
hitch manufacturer or by the trailer manufacturer. Followthe manufacturer's recommendation for attaching safety
chains and do not attach them to the bumper. Always
leave just enough slack so you can turn with your rig.
Never allow safety chains to drag on the ground.
Trailer Brakes
If your trailer weighs more than 1,000 lbs (450 kg)
loaded, then it needs its own brakes Ð and they must
be adequate. Be sure to read and follow the instructions
for the trailer brakes so you'll be able to install, adjust
and maintain them properly.
Your trailer brake system can tap into your vehicle's
hydraulic brake system, except:
·Don't tap into your vehicle's brake system if the
trailer's brake system will use more than 0.02 cubic
inch (0.3 cc) of ¯uid from your vehicle's master
cylinder. If it does, both braking systems won't work
well. You could even lose your brakes.
·Will the trailer parts take 3,000 psi (20 650 kPa) of
pressure? If not, the trailer brake system must not
be used with your vehicle.
·If everything checks out this far, then make the
brake ¯uid tap at the port on the master cylinder that
sends ¯uid to the rear brakes. But don't use
copper tubing for this. If you do, it will bend and
®nally break off. Use steel brake tubing.
4-40

Passing
You'll need more passing distance up ahead when
you're towing a trailer. And, because you're a good deal
longer, you'll need to go much farther beyond the
passed vehicle before you can return to your lane.
Backing Up
Hold the bottom of the steering wheel with one hand.
Then, to move the trailer to the left, just move that hand
to the left. To move the trailer to the right, move your
hand to the right. Always back up slowly and, if possible,
have someone guide you.
Making Turns
Notice:Making very sharp turns while trailering
could cause the trailer to come in contact with the
vehicle. Your vehicle could be damaged. Avoid
making very sharp turns while trailering.
When you're turning with a trailer, make wider turns
than normal. Do this so your trailer won't strike
soft shoulders, curbs, road signs, trees or other objects.
Avoid jerky or sudden maneuvers. Signal well in
advance.
Turn Signals When Towing a Trailer
When you tow a trailer, your vehicle has to have extra
wiring (included in the optional trailering package).
The arrows on your instrument panel will ¯ash whenever
you signal a turn or lane change. Properly hooked up,
the trailer lamps will also ¯ash, telling other drivers
you're about to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument
panel will ¯ash for turns even if the bulbs on the trailer
are burned out. Thus, you may think drivers behind
you are seeing your signal when they are not. It's
important to check occasionally to be sure the trailer
bulbs are still working.
Driving On Grades
Reduce speed and shift to a lower gearbeforeyou start
down a long or steep downgrade. If you don't shift
down, you might have to use your brakes so much that
they would get hot and no longer work well.
You can tow in DRIVE (D). You may want to shift the
transmission to THIRD (3) or, if necessary, a lower gear
selection if the transmission shifts too often (e.g.,
under heavy loads and/or hilly conditions).
4-42

Maintenance When Trailer Towing
Your vehicle will need service more often when you're
pulling a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transmission ¯uid (don't over®ll),
engine oil, axle lubricant, belt, cooling system and
brake system. Each of these is covered in this manual,
and the Index will help you ®nd them quickly. If
you're trailering, it's a good idea to review these sections
before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Trailer Wiring Harness
If you have the optional trailering package, your vehicle
will have an eight-wire harness, including the center
high-mounted stoplamp battery feed wire. The harness
is stored on the passenger's side of the vehicle near
the rear wheel well. This harness has a 30 amp battery
feed wire and no connector, and should be wired by
a quali®ed electrical technician. After choosing an
aftermarket trailer mating connector pair, have the
technician attach one connector to the eight-wire trailer
harness and the other connector to the wiring harness
on the trailer. Be sure the wiring harness on the trailer is
taped or strapped to the trailer's frame rail and leave
it loose enough so the wiring doesn't bend or break, but
not so loose that it drags on the ground. The eight-wireharness must be routed out of your vehicle between the
rear door and the ¯oor, with enough of the harness
left on both sides so that the trailer or the body won't pull
it. If you do not have the optional trailering package,
your vehicle will still have a trailering harness. The
harness is located near the passenger's side rear wheel
well. It consists of six wires that may be used by
after-market trailer hitch installers.
The technician can use the following color code chart
when connecting the wiring harness to your trailer.
·Brown: Rear lamps.
·Yellow: Left stoplamp and turn signal.
·Dark Green: Right stoplamp and turn signal.
·White (Heavy Gage): Ground.
·Light Green: Back-up lamps.
·White (Light Gage): Center High-Mounted Stoplamp.
·Blue: Auxiliary circuit (eight-wire harness only).
·Orange: Fused auxiliary (eight-wire harness only).
Store the harness in its original place. Wrap the
harness together and tie it neatly so it won't
be damaged.
4-44

Appearance Care............................................5-86
Cleaning the Inside of Your Vehicle.................5-87
Care of Safety Belts......................................5-89
Weatherstrips...............................................5-89
Cleaning the Outside of Your Vehicle..............5-90
Sheet Metal Damage.....................................5-92
Finish Damage.............................................5-93
Underbody Maintenance................................5-93
Chemical Paint Spotting.................................5-93
Vehicle Care/Appearance Materials..................5-94
Vehicle Identi®cation......................................5-95
Vehicle Identi®cation Number (VIN).................5-95
Service Parts Identi®cation Label.....................5-95Electrical System............................................5-95
Add-On Electrical Equipment..........................5-95
Headlamp Wiring..........................................5-96
Windshield Wiper Fuses................................5-96
Power Windows and Other Power Options.......5-96
Fuses and Circuit Breakers............................5-96
Capacities and Speci®cations........................5-102
Normal Maintenance Replacement Parts.........5-104
Engine Drive Belt Routing............................5-105
Section 5 Service and Appearance Care
5-2

Headlamp Wiring
The headlamp wiring is protected by a circuit breaker in
the lamp switch. An electrical overload will cause the
lamps to ¯icker on and off, or in some cases to remain
off. If this happens, have your headlamp wiring
checked right away.
Windshield Wiper Fuses
The windshield wiper motor is protected by a circuit
breaker and a fuse. If the motor overheats due to heavy
snow, etc., the wiper will stop until the motor cools.
Although the circuit is protected from electrical overload,
overload due to heavy snow, etc., may cause wiper
linkage damage. Always clear ice and heavy snow from
the windshield before using the windshield wipers. If
the overload is caused by some electrical problem and
not snow, etc., be sure to get it ®xed.
Power Windows and Other Power
Options
Circuit breakers in the fuse panel protect the power
windows and other power accessories. When the current
load is too heavy, the circuit breaker opens and
closes, protecting the circuit until the problem is ®xed or
goes away.
Fuses and Circuit Breakers
The wiring circuits in your vehicle are protected from
short circuits by a combination of fuses, circuit breakers
and fusible thermal links. This greatly reduces the
chance of ®res caused by electrical problems.
Look at the silver-colored band inside the fuse. If the
band is broken or melted, replace the fuse. Be sure you
replace a bad fuse with a new one of the identical
size and rating.
Spare fuses and a fuse puller are located in the
underhood fuse block. You can remove fuses with the
fuse puller. Remember to replace any of the spare fuses
you use, so you will have some if you ever need them
again.
If you ever have a problem on the road and don't have
a spare fuse, you can borrow one that has the same
amperage. Just pick some feature of your vehicle
that you can get along without ± like the radio or
cigarette lighter ± and use its fuse, if it is the correct
amperage. Replace it as soon as you can.
There are two fuse blocks in your vehicle: one is inside
the vehicle and one is in the engine compartment.
5-96

Feed Usage
AUX B Up®tter Battery Feed
AUX A Up®tter Accessory Feed
Relays Usage
A/C Relay
(Rear Heat
and A/C)Rear/Heat and Air ConditioningRelays Usage
Up®tter-ACCY
RelayUp®tter Accessory
Starter Enable
RelayStarter
A/C Enable
RelayAir Conditioning
Headlamps
RelayHeadlamps
Fuel Pump
RelayFuel Pump
Fuse/Circuit
BreakerUsage
UPFITTER-
BATTUp®tter Battery Power Stud, Trailer
Wiring Harness
UPFITTER-
ACCYUp®tter 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
5-100

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