2005 CHEVROLET ASTRO turn signal

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 qualied 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-wire harness
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.
4-45

Service............................................................5-3
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside
of Your Vehicle...........................................5-5
Fuel................................................................5-5
Gasoline Octane............................................5-5
Gasoline Specications....................................5-5
California Fuel...............................................5-6
Additives.......................................................5-6
Fuels in Foreign Countries...............................5-7
Filling Your Tank............................................5-8
Filling a Portable Fuel Container.....................5-10
Checking Things Under the Hood....................5-10
Hood Release..............................................5-11
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-13
Engine Cover...............................................5-17
Engine Air Cleaner/Filter................................5-21
Automatic Transmission Fluid.........................5-23
Engine Coolant.............................................5-26
Radiator Pressure Cap..................................5-28
Engine Overheating.......................................5-28
Cooling System............................................5-30
Engine Fan Noise.........................................5-35
Power Steering Fluid.....................................5-36Windshield Washer Fluid................................5-37
Brakes........................................................5-38
Battery........................................................5-42
Jump Starting...............................................5-42
All-Wheel Drive..............................................5-47
Rear Axle.......................................................5-48
Front Axle......................................................5-49
Bulb Replacement..........................................5-50
Halogen Bulbs..............................................5-50
Headlamps and Sidemarker Lamps.................5-50
Front Turn Signal and Parking Lamps..............5-54
Taillamps, Turn Signal, Stoplamps and
Back-up Lamps.........................................5-55
Replacement Bulbs.......................................5-56
Windshield Wiper Blade Replacement..............5-57
Tires..............................................................5-58
Tire Sidewall Labelling...................................5-59
Tire Terminology and Denitions.....................5-61
Ination - Tire Pressure.................................5-64
Tire Inspection and Rotation...........................5-65
When It Is Time for New Tires.......................5-66
Buying New Tires.........................................5-67
Uniform Tire Quality Grading..........................5-68
Wheel Alignment and Tire Balance..................5-69
Section 5 Service and Appearance Care
5-1

2. Pull the connector out
and unplug the lamp.
3. Plug the new lamp into the connector.
4. Reverse Steps 1 and 2 to reinstall the headlamp.Composite Headlamps
1. Open the hood. SeeHood Release on page 5-11
for more information.
2. Remove the two
screws from the
sidemarker/turn signal
lamp assembly.
5-51

3. Completely remove the sidemarker/turn signal lamp
assembly by pulling it out and disconnecting the
sidemarker/turn signal lamp sockets from the lamp.
Replace the sidemarker/turn signal bulb with a
new one if it needs to be replaced.4. Remove the screw
located behind the
corner reector
to remove the entire
corner reector.
5-52

Front Turn Signal and Parking
Lamps
1. Remove the two screws at the inside edge of the
parking/turn signal lamp assembly.
2. Remove the lamp assembly.
3. Squeeze the tab on
the side of the lamp
socket while turning
the socket
counterclockwise.4. Pull the socket out of the lamp assembly.
5. Pull the bulb from the socket.
6. Gently push the new bulb into the socket.
7. Put the socket back into the lamp assembly and
turn it clockwise until it locks.
8. Put the parking/turn signal lamp assembly back into
the vehicle and tighten the screws.
5-54

Taillamps, Turn Signal, Stoplamps
and Back-up Lamps
1. Open the rear door. SeeRear Doors on page 2-11
for more information.
2. Remove the
two screws from
behind the door.
3. Pull out the taillamp assembly so you can see
the socket.
5-55

4. Press the tab and
turn the socket
counterclockwise to
remove the socket
from the bezel. If the
socket does not have
a tab, turn the socket
counterclockwise to
remove the socket
from the bezel.
5. Remove the old bulb from the socket and replace it
with a new one.
6. Reverse Steps 1 through 4 to reinstall the taillamp.Replacement Bulbs
Exterior Lamp Bulb Number
Back-Up Lamps 1156
Headlamps
Composite High-Beam 9005
Composite Low-Beam 9006
Sealed-Beam Headlamps H6054
Parking, Turn Signal Lamps 3157NA
Sidemarker Lamps 194
Stoplamps 2057
For replacement bulbs not listed here, contact
your dealer.
5-56

Fuse/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
7 Power Outlets, Subwoofer Amplier
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
10 Air Bag SystemFuse/Circuit
BreakerUsage
11 Not Used
12Blower 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 Illumination, 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
Solenoid
5-97