climate control GMC YUKON 2002 Owner's Manual

2-31
Engine Exhaust
CAUTION:
Engine exhaust can kill. It contains the gas
carbon monoxide (CO), which you can't see or
smell. It can cause unconsciousness and death.
You might have exhaust coming in if:

Your exhaust system sounds strange
or different.

Your vehicle gets rusty underneath.

Your vehicle was damaged in a collision.

Your vehicle was damaged when driving over
high points on the road or over road debris.

Repairs weren't done correctly.

Your vehicle or exhaust system had been
modified improperly.
If you ever suspect exhaust is coming into
your vehicle:

Drive it only with all the windows down to
blow out any CO; and

Have your vehicle fixed immediately.
Running Your Engine While
You're Parked
It's better not to park with the engine running. But if you
ever have to, here are some things to know.
CAUTION:
Idling the engine with the climate control
system off could allow dangerous exhaust into
your vehicle. See the earlier Caution under
ªEngine Exhaust.º
Also, idling in a closed-in place can let deadly
carbon monoxide (CO) into your vehicle even
if the fan is at the highest setting. One place
this can happen is a garage. Exhaust
-- with
CO
-- can come in easily. NEVER park in a
garage with the engine running.
Another closed-in place can be a blizzard.
See ªBlizzardº in the Index.

3-6
When both the fan control and mode knobs are in the
AUTO position, the system will then automatically
maintain the desired cabin temperature as selected.
Manual control of functions is also available.
Temperature Knob
The middle knob on the control panel lets you select the
desired air temperature in your vehicle. This knob will
allow you to adjust the interior air temperature
independent of the function knob setting. Move the knob
clockwise toward 82
F (28
C) for warmer air. Move the
knob counterclockwise toward 66
F (19
C) for cooler
air. When the system is set for automatic operation,
sensors will control the fan speed.
Full Hot: If you turn the temperature knob past 82
F
(28
C), the system will go into the ªfull hotº mode. The
system will remain at that maximum heating setting and
the fan will blow at the speed the fan knob is set to. If
the fan is in AUTO, it will run at full speed.
Full Cold: If you turn the temperature knob past 66
F
(19
C), the system will go into the ªfull coldº mode.
The system will remain at that maximum cooling setting
and the fan will blow at the speed the fan knob is set to.
If the fan is in AUTO, it will run at full speed.Mode Knob -- Manual Operation
The right knob on the control panel allows you to
choose the direction of air delivery.
You can choose to set the climate control system
yourself, or let the system work for you by placing the
system in AUTO mode. See ªMode Knob
-- Automatic
Operationº later in this section.
(Vent): This setting directs most of the air through
the instrument panel outlets and a small amount through
the floor outlets.
(Bi-Level): Air is delivered through the floor
outlets as well as the instrument panel outlets.
(Floor): This setting directs most of the warmed
air through the floor outlets and some air through the
windshield defroster outlets.
(Blend): Airflow is divided equally between the
floor outlet and the windshield defroster outlets. The air
conditioning compressor may run to dehumidify the air
to prevent window fogging.

3-12 Rear Air Conditioning and Heating
Systems with Electronic Climate Control
System (If Equipped)
Front Control
Rear ControlWith this system the rear passengers can control the
temperature of the air flow for the rear seating area. The
climate control has three controls.
To adjust the airflow speed, turn the fan knob located on
the left side of the control panel.
The system also has a front AUTO setting that can
automatically change the temperature of the rear seating
area based on information from the front control. An
OFF setting, located on the front climate control panel,
also allows the driver to turn off the rear passenger seat
controls from the front seat.
To adjust the air temperature, turn the temperature knob
on the center of the control panel clockwise toward
82
F (28
C) for warmer air. Turn the knob
counterclockwise toward 66
F (19
C) for cooler air.
To regulate the airflow location, adjust the right knob
on the control panel. Turn the knob clockwise for floor
outlets airflow or counterclockwise for headliner vent
airflow. Generally, the instrument panel outlets are used
for air conditioning and the floor vents for heating. The
knob can be set to any blend setting.

6-54 Uniform Tire Quality Grading
Quality grades can be found where applicable on the tire
sidewall between tread shoulder and maximum section
width. For example:
Treadwear 200 Traction AA Temperature A
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration, which grades tires by
treadwear, traction and temperature performance.
(This applies only to vehicles sold in the United States.)
The grades are molded on the sidewalls of most
passenger car tires. The Uniform Tire Quality Grading
system does not apply to deep tread, winter
-type snow
tires, space
-saver or temporary use spare tires, tires with
nominal rim diameters of 10 to 12 inches (25 to 30 cm),
or to some limited
-production tires.
While the tires available on General Motors passenger
cars and light trucks may vary with respect to these
grades, they must also conform to federal safety
requirements and additional General Motors Tire
Performance Criteria (TPC) standards.Treadwear
The treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions on a specified government test course.
For example, a tire graded 150 would wear one and a
half (1 1/2) times as well on the government course
as a tire graded 100. The relative performance of tires
depends upon the actual conditions of their use,
however, and may depart significantly from the norm
due to variations in driving habits, service practices and
differences in road characteristics and climate.
Traction
-- AA, A, B, C
The traction grades, from highest to lowest, are AA,
A, B, and C. Those grades represent the tire's ability to
stop on wet pavement as measured under controlled
conditions on specified government test surfaces of
asphalt and concrete. A tire marked C may have poor
traction performance. Warning: The traction grade
assigned to this tire is based on straight
-ahead braking
traction tests, and does not include acceleration,
cornering, hydroplaning, or peak traction characteristics.

6-70
Instrument Panel Fuse Block
The fuse block access door
is on the driver's side edge
of the instrument panel. Pull
off the cover to access the
fuse block.
You can remove fuses with a fuse extractor which is
mounted to the fuse block access door. To remove fuses
if you don't have a fuse extractor, hold the end of the
fuse between your thumb and index finger and pull
straight out.
You may have spare fuses located behind the fuse block
access door. These can be used to replace a bad fuse.
However, make sure it is of the correct amperage.
Fuse Usage
HVAC 1 Climate Control System
IGN 3 Ignition, Power Seats
BRAKE Anti
-Lock Brake System

6-71
Fuse Usage
HTR A/C Climate Control System
IGN 0 PRND321 Display,
Odometer, PCM
CRUISE Cruise Control, Instrument Cluster
4WD Four
-Wheel Drive System,
Auxiliary Battery
TURN Exterior Lamps, Turn Signals,
Hazard Lamps
RR WIPER Rear Window Wiper
WS WPR Windshield Wipers
SEO IGN Special Equipment Option,
Ignition, OnStar


ILLUM Interior Lamps
IGN 1 Ignition, Instrument Panel
SEO ACCY Special Equipment Option
Accessory, Cellular Telephone
L BODY Retained Accessory Power Relay
CRANK Starting SystemFuse Usage
AIR BAG Air Bag
MIR/LOCK Power Mirrors, Power Door Locks
SEAT Power Seat Circuit Breaker
DR LOCK Power Door Locks
RAP #1 Retained Accessory Power Relay
LOCK Power Door Locks
INT PRK Interior Lamps
UNLOCK Power Door Locks
DRV UNLOCK Power Door Lock Relay
L DOOR Power Door Lock Relay
PWR WDO Power Window Circuit Breaker
RDO I Audio System, OnStar

RAP #2 Rear Power Windows, Sunroof,
Radio, OnStar

LOCK Power Door Lock Relay
UNLOCK Power Door Lock Relay

6-75
Fuse Usage
STUD #1 Accessory Power/Trailer Wiring
Feed/Load Leveling
ABS Anti
-Lock Brakes
IGN A Ignition Switch
AIR A.I.R. System
RAP #1 Retained Accessory Power, Power
Mirrors, Power Door Locks,
Power Seat(s)
IGN B Ignition Switch
RAP #2 Retained Accessory Power/Rear
Power Windows, Sunroof, Radio
STUD #2 Accessory Power/Trailer Wiring
Brake Feed
TRL R TRN Right Turn Signal Trailer Wiring
TRL L TRN Left Turn Signal Trailer Wiring
IGN 1 Ignition, Fuel Controls
INJ B Ignition, Fuel Controls (Relay)
STARTER Starter (Relay)Fuse Usage
PARK LP Parking Lamps
FRT HVAC Climate Control System
STOP LP Exterior Lamps, Stoplamps
ECM I PCM
CHMSL Center High Mounted Stoplamp
VEH STOP Stoplamps, Cruise Control
TRL B/U Backup Lamps Trailer Wiring
INJ A Fuel Controls, Ignition
RR HVAC Rear HVAC
VEH B/U Vehicle Backup Lamps
ENG 1 Engine Controls, Canister Purge,
Fuel System
ETC Electronic Throttle Control
IGN E A/C Compressor Relay, Rear
Window Defogger, Daytime
Running Lamps, A.I.R. System
B/U LP Backup Lamps, Automatic
Transmission Shift Lock
Control System

6-76
Fuse Usage
ATC Automatic Transfer Case
RR DEFOG Rear Window Defogger, Heated
Mirrors (Relay)
RTD Autoride
(Real Time Damping)
RR PRK Right Rear Parking Lamps
ECM B PCM
F/PMP Fuel Pump (Relay)
O2 A Oxygen Sensors
O2 B Oxygen Sensors
LR PRK Left Rear Parking Lamps
RR DEFOG Rear Window Defogger,
Heated Mirrors
HDLP Headlamps (Relay)
TRL PRK Parking Lamps Trailer Wiring
PRIME Not Used
RT HDLP Right Headlamps
DRL Daytime Running Lamps (Relay)
HTD MIR Heated MirrorsFuse Usage
LT HDLP Left Headlamps
A/C Air Conditioning
AUX PWR Cigarette Lighter, Auxiliary
Power Outlets
SEO 2 Special Equipment Option Power,
Power Seats, Aux Roof Mnt Lamp
SEO 1 Special Equipment Option
Power, Aux Roof Mnt Lamp,
Cell Phone, OnStar


DRL Daytime Running Lamps
A/C A/C (Relay)
FOG LP Fog Lamps
FOG LP Fog Lamps (Relay)
RADIO Audio System, Instrument Cluster,
Climate Control System
CIGAR Cigarette Lighter, Auxiliary
Power Outlets
RT TURN Right Turn Signals
BTSI Automatic Transmission Shift
Lock Control System