air conditioning CHEVROLET EXPRESS 2004 Owners Manual

Instrument Panel Overview...............................3-4
Hazard Warning Flashers................................3-6
Other Warning Devices...................................3-6
Horn.............................................................3-6
Tilt Wheel.....................................................3-6
Turn Signal/Multifunction Lever.........................3-7
Turn and Lane-Change Signals........................3-8
Headlamp High/Low-Beam Changer..................3-8
Flash-to-Pass.................................................3-9
Windshield Wipers..........................................3-9
Windshield Washer.......................................3-10
Cruise Control..............................................3-10
Exterior Lamps.............................................3-13
Headlamps on Reminder................................3-14
Daytime Running Lamps (DRL).......................3-14
Instrument Panel Brightness...........................3-15
Dome Lamps...............................................3-15
Dome Lamp Override....................................3-15
Entry Lighting...............................................3-16
Exit Lighting.................................................3-16
Reading Lamps............................................3-16
Battery Run-Down Protection..........................3-16
Accessory Power Outlets...............................3-16
Ashtrays and Cigarette Lighter........................3-17Climate Controls............................................3-18
Climate Control System.................................3-18
Outlet Adjustment.........................................3-20
Rear Heating System....................................3-20
Rear Air Conditioning and Heating System.......3-21
Warning Lights, Gages, and Indicators............3-22
Instrument Panel Cluster................................3-23
Speedometer and Odometer...........................3-24
Trip Odometer..............................................3-24
Engine Speed Limiter....................................3-24
Safety Belt Reminder Light.............................3-25
Airbag Readiness Light..................................3-25
Airbag Off Light............................................3-26
Charging System Light..................................3-28
Voltmeter Gage............................................3-28
Brake System Warning Light..........................3-29
Anti-Lock Brake System Warning Light.............3-30
StabiliTrak Not Ready Light............................3-30
StabiliTrak Indicator Light...............................3-31
Engine Coolant Temperature Gage..................3-31
Malfunction Indicator Lamp.............................3-32
Oil Pressure Gage........................................3-34
Change Engine Oil Light................................3-35
Security Light...............................................3-36
Section 3 Instrument Panel
3-1

Climate Controls
Climate Control System
With this system you can control the heating, cooling
and ventilation for your vehicle.
Turn the right knob clockwise or counterclockwise to
direct the airow inside of your vehicle.
To change the current mode, select one of the following:
H(Vent):This mode directs air to the instrument
panel outlets.
)(Bi-Level):This mode directs about half of the air
to the instrument panel outlets, then directs most of
the remaining air to the oor outlets. Some air may be
directed toward the windshield.
6(Floor):This mode directs most of the air to the
oor outlets with some air directed to the outboard
outlets (for the side windows) and some air directed to
the windshield.The right knob can also be used to select the defrost
and defog modes. Information on defogging and
defrosting can be found later in this section.
9(Fan):Turn the left knob clockwise or
counterclockwise to increase or decrease the fan speed.
Temperature Control:Turn the center knob clockwise
or counterclockwise to increase or decrease the
temperature inside your vehicle.
If your vehicle has air conditioning, your heating/air
conditioning controls will look like this:
On hot days, open the windows to let hot inside air
escape; then close them. This helps to reduce the time
it takes for your vehicle to cool down. It also helps
the system to operate more efficiently.
A/C (Air Conditioning):This setting will begin to cool
and dehumidify the air inside of your vehicle.
MAX A/C (Maximum Air Conditioning):Turn the right
knob to MAX A/C for maximum cooling. This setting
cools the air the fastest, by recirculating the inside air.
3-18

Defogging and Defrosting
Fog on the inside of windows is a result of high humidity
(moisture) condensing on the cool window glass. This
can be minimized if the climate control is used properly.
There are two modes to clear fog or frost from your
windshield and side windows.
Use the defog mode to clear the windows of fog or
moisture and warm the passengers. Use the defrost
mode to remove fog or frost from the windshield more
quickly. For best results, clear all snow and ice from the
windshield before defrosting.
Turn the knob on the right of the climate control panel
to select the defog or defrost mode.
-(Defog):With this setting, the outside air comes out
of both the oor and defroster outlets. Adjust the
temperature knob for warmer or cooler air. The air
conditioning compressor may operate in this setting to
dehumidify the air.
1(Defrost):This setting operates the defroster. Most
of the air comes out near the windshield, with some
going to the oor outlets and front side windows. The air
conditioning compressor may operate in this setting to
dehumidify the air.The defog setting is useful for cold weather with a large
number of passengers or very humid conditions to
help keep the windshield clear. Use defrost to remove
fog or ice from the windshield quickly in extremely
cold conditions. The temperature knob should be in the
red area and the fan control toward high. Do not
drive the vehicle until all the windows are clear.
Rear Window Defogger
Some vehicles may have a rear window defogger.
<R. DEF (Rear Defrost):Press this button to turn
the rear window defogger on or off. Be sure to clear
as much snow from the window as possible.
The rear window defogger uses a warming grid to
remove fog or frost from the rear window and will only
work when the ignition is RUN.
The rear window defogger will turn off several minutes
after the button is pressed. If turned on again, the
defogger will run for several more minutes before turning
off. The defogger can also be turned off by pressing
the button again or by turning off the engine.
Notice:Using a razor blade or sharp object to clear
the inside rear window may damage the rear
window defogger. Repairs would not be covered by
your warranty. Do not clear the inside of the rear
window with sharp objects.
3-19

Rear Air Conditioning and
Heating System
Your vehicle may have a rear heating and
air-conditioning system. This system regulates the
temperature, the fan speed and the air delivery for the
rear-seat passengers only. It also works with the
main climate-control system in your vehicle.
Use this control panel when you would like to maintain
a separate temperature setting. Adjust the direction
of the airow or adjust the fan speed for the rear-seat
passenger(s).If your vehicle has a 135 inch (343 cm) wheelbase, a
rear control panel for this system is located in the
second row behind the driver in the rear of your vehicle.
A rear-seat passenger can use this control panel to
personally adjust the temperature, the direction of the
airow and the fan speed for the rear-seating area.
The fan knob located on the front climate control panel
must be turned to REAR CNTL to allow a rear-seat
passenger to use the control panel in the rear-seating
area. Performing this action disables the front control
panel. To return control to this panel, move the fan knob
out of REAR CNTL.
Turn the center knob clockwise or counterclockwise
to change the direction of the airow in the
rear-seating area. Front Climate-Control Panel
Rear Climate-Control Panel
3-21

To change the current mode, select one of the following:
D(Vent):Use this mode to direct air to the upper
outlets, with a little air directed to the oor outlets.
2(Floor):Use this mode to direct most of the air to
the oor outlets.
9(Fan):Turn the left knob clockwise or
counterclockwise to HIGH, MED (Medium) or LOW to
increase or decrease the fan speed in the rear-seating
area. Turn the knob to OFF to turn off the fan.
Temperature Control:To increase or decrease the
temperature for the rear of the vehicle, turn the
right knob located on the climate-control panel.
The air-conditioning system on the main climate-control
panel must be turned on to direct cooled air to the rear of
the vehicle. If it is not on, then the temperature in the rear
of the vehicle will remain at cabin temperature.
Be sure to keep the area under the front seats clear of
any objects so that the air inside of your vehicle can
circulate effectively.
For information on how to use the main climate-control
system, seeClimate Control System on page 3-18.
For information on ventilation, seeOutlet Adjustment on
page 3-20.
Warning Lights, Gages, and
Indicators
This part describes the warning lights and gages that
may be on your vehicle. The pictures will help you
locate them.
Warning lights and gages can signal that something is
wrong before it becomes serious enough to cause
an expensive repair or replacement. Paying attention to
your warning lights and gages could also save you
or others from injury.
Warning lights come on when there may be or is a
problem with one of your vehicle’s functions. As you will
see in the details on the next few pages, some
warning lights come on briey when you start the
engine just to let you know they’re working. If you are
familiar with this section, you should not be alarmed
when this happens.
Gages can indicate when there may be or is a problem
with one of your vehicle’s functions. Often gages
and warning lights work together to let you know when
there’s a problem with your vehicle.
When one of the warning lights comes on and stays on
when you are driving, or when one of the gages shows
there may be a problem, check the section that tells you
what to do about it. Please follow this manual’s advice.
Waiting to do repairs can be costly – and even
dangerous. So please get to know your warning lights
and gages. They’re a big help.
3-22

Tire Terminology and Denitions
Air Pressure:The amount of air inside the tire pressing
outward on each square inch of the tire. Air pressure
is expressed in pounds per square inch (psi) or
kiloPascal (kPa).
Accessory Weight:This means the combined weight
of optional accessories. Some examples of optional
accessories are, automatic transmission, power steering,
power brakes, power windows, power seats, and
air conditioning.
Aspect Ratio:The relationship of a tire’s height to
its width.
Belt:A rubber coated layer of cords that is located
between the plies and the tread. Cords may be made
from steel or other reinforcing materials.
Bead:The tire bead contains steel wires wrapped by
steel cords that hold the tire onto the rim.
Bias Ply Tire:A pneumatic tire in which the plies are
laid at alternate angles less than 90 degrees to the
centerline of the tread.Cold Ination Pressure:The amount of air pressure in
a tire, measured in pounds per square inch (psi) or
kilopascals (kPa) before a tire has built up heat
from driving. SeeInation - Tire Pressure on page 5-58.
Curb Weight:This means the weight of a motor
vehicle with standard and optional equipment including
the maximum capacity of fuel, oil and coolant, but
without passengers and cargo.
DOT Markings:A code molded into the sidewall of a
tire signifying that the tire is in compliance with the U.S.
Department of Transportation (DOT) motor vehicle
safety standards. The DOT code includes the Tire
Identication Number (TIN), an alphanumeric designator
which can also identify the tire manufacturer, production
plant, brand and date of production.
GVWR:Gross Vehicle Weight Rating, seeLoading
Your Vehicle on page 4-29.
GAWR FRT:Gross Axle Weight Rating for the front
axle, seeLoading Your Vehicle on page 4-29.
GAWR RR:Gross Axle Weight Rating for the rear axle,
seeLoading Your Vehicle on page 4-29.
5-56

Fuse Usage
6 Ignition 0
7 Stoplamp
8 Right Rear Defogger/Heated Mirror
9Right Daytime Running
Lamp/Turn Signal
10Left Daytime Running
Lamp/Turn Signal
11 Truck Body Control Module 4
12 Fuel Pump
13 Trailer
14 Flasher
15 Horn
16 Truck Body Control Module 3
17 Trailer Stop/Turn Signal
18 Truck Body Control Module 2
19 Truck Body Control Module
20 Remote Function Actuator
21 Engine 2Fuse Usage
22 Ignition E
23 Engine 1
24Truck Body Control Module
Ignition 1
25 Spare
26 RPA/Inside Rearview Mirror
27 Crankcase
28Brake Transmission Shift
Interlock System
29 Auxiliary Power Outlets
30 Cigarette Lighter
31 Instrument Panel Cluster
32 Air Conditioning
33 Spare
34 Vent
35 Spare
36 Vehicle Back Up
37Supplemental Inatable
Restraint System
5-95

Fuse Usage
38 Powertrain Control Module Ignition 1
39 Oxygen Sensor B
40 Oxygen Sensor A
41 Windshield Wipers
42 Right Headlamp - Low Beam
43 Left Headlamp - Low Beam
44 Left Headlamp - High Beam
45 Right Headlamp - High Beam
46Truck Body Control
Module-Accessory
47 Front Windshield Wiper
48 Anti-Lock Brakes
49 Ignition A
50 Trailer
51 Climate Control Blower
52 Ignition B
63 Spare
64 SpareFuse Usage
Relays Usage
53 Windshield Wiper
54 Air Conditioning
55 Spare
56 Headlamp - High Beam
57 Fuel Pump
58 Headlamp - Low Beam
59 Horn
61 Starter
62 Spare
Circuit Breaker Usage
60 Power Seat
5-96

Capacities and Specications
The following approximate capacities are given in English and metric conversions. SeeRecommended Fluids and
Lubricants on page 6-13for more information. When adding, be sure to ll to the appropriate level or as
recommended in this manual.
See refrigerant charge label under the hood for charge capacity information and requirements.
ApplicationCapacities
English Metric
Air Conditioning Refrigerant R134a
Front A/C
Front and Rear A/C1.8 lbs
3.1 lbs0.81 kg
1.41 kg
Cooling System
4300 V6
4800 V8, 5300 V8
6000 V811.0 quarts
13.4 quarts
14.8 quarts10.4 L
12.7 L
14.0 L
Cooling System with Rear Heat
4300 V6
4800 V8, 5300 V8
6000 V814.0 quarts
16.4 quarts
17.8 quarts13.2 L
15.5 L
17.0 L
Engine Oil with Filter
4300 V6
4800 V, 5300 V8
6000 V84.5 quarts
6.0 quarts
6.0 quarts4.3 L
5.7 L
5.7 L
5-97

Maintenance Footnotes
†The 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, kingpin bushings,
steering linkage and rear driveline center splines.
(a)Visually inspect brake lines and hoses for proper
hook-up, binding, leaks, cracks, chang, etc. Inspect
disc brake pads for wear and rotors for surface
condition. Inspect other brake parts, including calipers,
parking brake, etc.
(b)Visually inspect front and rear suspension and
steering system for damaged, loose or missing parts,
signs of wear or lack of lubrication. Inspect power
steering lines and hoses for proper hook-up, binding,
leaks, cracks, chang, etc.
(c)Visually inspect hoses and have them replaced if
they are cracked, swollen or deteriorated. Inspect
all pipes, ttings and clamps; replace with genuine
GM parts as needed. To help ensure proper operation,a pressure test of the cooling system and pressure cap
and cleaning the outside of the radiator and air
conditioning condenser is recommended at least
once a year.
(d)Visually inspect wiper blades for wear or cracking.
Replace blade inserts that appear worn or damaged
or that streak or miss areas of the windshield.
(e)Make sure the safety belt reminder light and all your
belts, buckles, latch plates, retractors and anchorages
are working properly. Look for any other loose or
damaged safety belt system parts. If you see anything
that might keep a safety belt system from doing its
job, have it repaired. Have any torn or frayed safety belts
replaced. Also look for any opened or broken airbag
coverings, and have them repaired or replaced.
(The airbag system does not need regular maintenance.)
(f)Lubricate all key lock cylinders, hood hinges, hood
prop rod pivot, hood latch assembly, secondary
latch, pivots, spring anchor, release pawl, rear
compartment hinges, latches, locks, fuel door hinge and
any moving seat hardware. More frequent lubrication
may be required when exposed to a corrosive
environment. Applying silicone grease on weatherstrips
with a clean cloth will make them last longer, seal
better and not stick or squeak.
6-8