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Envoy XL
To operate the rear air conditioning system, the front
air conditioning system must be on. With the front
air conditioning system off, the rear system controls can
only be used to circulate air in the rear of the vehicle.
To adjust the air ow
speed, turn the fan knob
(driver override switch),
located on the oor
console to 1, 2 or 3.
The rear mode and
temperature positions
now mimic the front
control system mode
and passenger side
temperature.
H(Panel):When panel mode is selected in the front
controller, the rear system will distribute air from the
four headliner outlets.
)(Bi-level):When bi-level mode is selected in the
front controller, the rear system will distribute air from the
four headliner outlets and the third seat oor outlet.
6(Floor):When oor mode is selected in the front
controller, the rear system will distribute air from the
third seat oor outlet.
-(Defog):When defog mode is selected in the front
controller, the rear system will distribute air from the
third seat oor outlet.
0(Defrost):When defrost mode is selected in the
front controller, the rear system will distribute air
from the third seat oor outlet.
To activate the second row seat controls in the
following systems, set the fan knob, located on the
front console, to R.
Envoy XL
3-32
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(D) Construction Code:A letter code is used to
indicate the type of ply construction in the tire. The letter
“R” means radial ply construction; the letter “D” means
diagonal or bias ply construction; and the letter “B”
means belted-bias ply construction.
(E) Rim Diameter:Diameter of the wheel in inches.
(F) Service Description:The service description
indicates the load range and speed rating of a tire.
The load index can range from 1 to 279. Speed ratings
range from “A” to “Z”. The light truck tire size example
above shows dual or single tire con gurations.
Tire Terminology and De nitions
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 In ation 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. SeeIn ation - Tire Pressure on page 5-64.
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 motor vehicle
safety standards. The DOT code includes the Tire
Identi cation Number (TIN), an alphanumeric designator
which can also identify the tire manufacturer, production
plant, brand and date of production.
5-61
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Fuses Usage
29 Oxygen Sensor
30 Air Conditioning
31 Truck Body Controller
32 Trailer
33 Anti-Lock Brakes (ABS)
34 Ignition A
35 Blower Motor
36 Ignition B
50 Passenger’s Side Trailer Turn
51 Driver’s Side Trailer Turn
52 Hazard Flashers
53 Electric Adjustable Pedal
54 A.I.R. Solenoid
56 A.I.R. PumpRelays Usage
37 Headlamp Washer
38 Rear Window Washer
39 Fog Lamps
40 Horn
41 Fuel Pump
42 Windshield Washer
43 High-Beam Headlamp
44 Air Conditioning
45 Cooling Fan
46 Headlamp Driver Module
47 Starter
49 Electric Adjustable Pedal
55 A.I.R. Solenoid
Miscellaneous Usage
48 Instrument Panel Battery
49 Blank
5-100
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Fuses Usage
30 Air Conditioning
31 Truck Body Controller 1
32 Trailer
33 Anti-Lock Brakes (ABS)
34 Ignition A
35 Blower Motor
36 Ignition B
50 Passenger’s Side Trailer Turn
51 Driver’s Side Trailer Turn
52 Hazard Flashers
53 Oxygen Sensor Bank B
54 Oxygen Sensor Bank A
55 Injector Bank A
56 Injector Bank B
57 Electric Adjustable PedalRelays Usage
37 Headlamp Washer
38 Rear Window Washer
39 Fog Lamps
40 Horn
41 Fuel Pump
42 Windshield Washer
43 High-Beam Headlamp
44 Air Conditioning
45 Cooling Fan
46 Headlamp Driver Module
47 Starter
49 Electric Adjustable Pedal
58 Ignition 1
Miscellaneous Usage
48 Instrument Panel Battery
5-103
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Fuses Usage
35 Blank
36Heat Ventilation
Air Conditioning B
37 Front Parking Lamps
38 Left Turn Signal
39Heat Ventilation
Air Conditioning 1
40 Truck Body Controller 4
41 Radio
42 Trailer Park
43 Right Turn Signal
44Heat Ventilation
Air Conditioning
45 Rear Fog Lamps
46 Auxiliary Power 1
47 Ignition 0Fuses Usage
48 Four-Wheel Drive
49 Blank
50 Truck Body Controller Ignition
51 Brakes
52 Truck Body Controller Run
Envoy XL
5-106
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Fuses Usage
18 Locks
19Liftgate Module/Driver Seat
Module
20 Vent Window
21 Lock
22 Retained Accessory Power
23 Blank
24 Unlock
25 Blank
26 Blank
27 OH Battery/OnStar
®System
28 Sunroof
29 Rainsense™ Wipers
30 Parking Lamps
31 Truck Body Controller Accessory
32 Truck Body Controller 5
33 Front Wipers
34 Vehicle Stop
35 Blank
Fuses Usage
36Heat Ventilation
Air Conditioning B
37 Front Parking Lamps
38 Left Turn Signal
39Heat Ventilation
Air Conditioning 1
40 Truck Body Controller 4
41 Radio
42 Trailer Park
43 Right Turn Signal
44Heat Ventilation
Air Conditioning
45 Rear Fog Lamps
46 Auxiliary Power 1
47 Ignition 0
48 Four-Wheel Drive
49 Blank
50 Truck Body Controller Ignition
51 Brakes
52 Truck Body Controller Run
5-108
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