2002 GMC SONOMA heating

2-62
To use the lighter, press it in all the way, and let go.
When it's ready, it will pop back out by itself.
NOTICE:
Don't hold a cigarette lighter in with your hand
while it is heating. If you do, it won't be able to
back away from the heating element when it's
ready. That can make it overload, damaging the
lighter and the heating element.
Sun Visors
To block out glare, you can swing down the sun visor.
You can also swing the visor from side to side.
Accessory Power Outlets
With accessory power outlets you can plug in auxiliary
electrical equipment such as a cellular telephone or CB
radio.
There are two accessory power outlets located near the
center of the vehicle on the lower part of the instrument
panel. A small cap must be pulled down to access an
accessory power outlet. When not using an outlet be
sure to cover it with the protective cap.
NOTICE:
When using accessory power outlets:

Maximum load of any electrical equipment
should not exceed 20 amps.

Be sure to turn off any electrical equipment
when not in use. Leaving electrical
equipment on for extended periods can
drain the battery.

2-75 Anti-Lock Brake System Warning Light
With the anti-lock brake
system, this light will come
on when you start your
engine and may stay on
for several seconds.
That's normal.
If the light stays on, or comes on when you're driving,
your vehicle needs service. If the regular brake system
warning light isn't on, you still have brakes, but you
don't have anti
-lock brakes. If the regular brake system
warning light is also on, you don't have anti
-lock brakes
and there's a problem with your regular brakes. See
ªBrake System Warning Lightº earlier in this section.
The anti
-lock brake system warning light should come
on briefly when you turn the ignition key to RUN. If the
light doesn't come on then, have it fixed so it will be
ready to warn you if there is a problem.
Engine Coolant Temperature Gage
United States Canada
This gage shows the engine coolant temperature. If the
gage pointer moves into the red area, your engine is
too hot!
It means that your engine coolant has overheated. If you
have been operating your vehicle under normal driving
conditions, you should pull off the road, stop your
vehicle and turn off the engine as soon as possible. See
ªEngine Overheatingº in the Index.

3-
3-1
Section 3 Comfort Controls and Audio Systems
In this section, you'll find out how to operate the comfort control and audio systems offered with your vehicle.
Be sure to read about the particular systems supplied with your vehicle.
3
-2 Comfort Controls
3-2 Standard Climate Control System
3-3 Optional Climate Control System
3-5 Air Conditioning (If Equipped)
3-5 Heating
3-6 Defogging and Defrosting
3-6 Ventilation System
3-7 Audio Systems
3-7 Setting the Clock for Systems with
SET Button
3
-7 Setting the Clock for Systems with HR and
MN Buttons
3
-8 Setting the Clock for Systems with Radio
Data System (RDS)
3
-8AM-FM Stereo
3-10 AM-FM Stereo
3-13 AM-FM Stereo with Cassette Tape Player
(If Equipped)
3
-16 AM-FM Stereo with Cassette Tape Player and
Automatic Tone Control (If Equipped)
3
-21 AM-FM Stereo with Compact Disc Player and
Automatic Tone Control (If Equipped)3
-26 AM-FM Stereo with Compact Disc Player
with Radio Data System (RDS) and Automatic
Tone Control (If Equipped)
3
-34 AM-FM Stereo with Cassette Tape and
Compact Disc Player with Radio Data System
(RDS) and Automatic Tone Control
(If Equipped)
3
-44 AM-FM Stereo with Six-Disc Compact Disc
Player with Programmable Equalization and
Radio Data System (RDS) (If Equipped)
3
-56 Remote Cassette Tape Player (If Equipped)
3-58 Theft-Deterrent Feature (If Equipped)
3-60 Theft-Deterrent Feature RDS Radios
(If Equipped)
3
-60 Understanding Radio Reception
3-61 Tips About Your Audio System
3-62 Care of Your Cassette Tape Player
3-63 Care of Your Remote Cassette Tape Player
3-64 Care of Your Compact Discs
3-64 Care of Your Compact Disc Player
3-64 Fixed Mast Antenna

3-2
Comfort Controls
With these systems, you can control the heating, cooling
and ventilation in your vehicle.
Standard Climate Control System
Fan Control
The knob on the left side of the climate control system
panel is used to adjust the fan speed. To increase airflow,
turn the knob clockwise. To decrease airflow, turn it
counterclockwise.
Temperature Knob
The middle knob on the control panel lets you select the
relative temperature of the air flowing into the passenger
area of your vehicle. Turn the knob clockwise toward
the red area for warmer air. Turn the knob
counterclockwise toward the blue area for cooler air.

3-5 Air Conditioning (If Equipped)
On hot days, open the windows long enough to let hot
inside air escape. This reduces the time it takes for your
vehicle to cool down. Then keep your windows closed
for the air conditioner to work its best.
For quick cool
-down on very hot days, use MAX A/C
with the temperature knob turned counterclockwise.
This setting should be used to keep odors and/or dust
from entering the vehicle. For normal cooling on hot
days, use A/C with the temperature knob turned
counterclockwise.
On cool but sunny days, use bi
-level to deliver warm
air to the floor and cooler air to the instrument
panel outlets.
If you have the VORTEC 4300 V6 engine, when the air
conditioner is on, you may sometimes notice slight
changes in your vehicle's engine speed and power. This
is normal because the system is designed to cycle the
compressor on and off to keep the desired temperature.
Heating
The heater works best if you keep your windows closed
while using it. On cold days, use the floor outlets with
the temperature knob turned clockwise. Blend is useful
in cool weather when you have fog or ice on the
windshield or side windows.
If you use the optional engine coolant heater before
starting your engine, your heating system will produce
warmer air faster to heat the passenger compartment in
cold weather. See ªEngine Coolant Heaterº in the Index.

4-59 Driving On Grades
Reduce speed and shift to a lower gear before you 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.
If you have an automatic transmission, you should use
THIRD (3) when towing a trailer. Operating your
vehicle in THIRD (3) when towing a trailer will
minimize heat buildup and extend the life of your
transmission. Or, if you have a manual transmission, it's
better not to use FIFTH (5). Just drive in FOURTH (4)
(or, as you need to, a lower gear).
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a
lower temperature than at normal altitudes. If you turn
your engine off immediately after towing at high altitude
on steep uphill grades, your vehicle may show signs
similar to engine overheating. To avoid this, let the
engine run while parked (preferably on level ground)
with the automatic transmission in PARK (P) (or the
manual transmission out of gear and the parking brake
applied) for a few minutes before turning the engine off.
If you do get the overheat warning, see ªEngine
Overheatingº in the Index.
Parking on Hills
CAUTION:
You really should not park your vehicle, with a
trailer attached, on a hill. If something goes
wrong, your rig could start to move. People can
be injured, and both your vehicle and the trailer
can be damaged.
But if you ever have to park your rig on a hill, here's
how to do it:
1. Apply your regular brakes, but don't shift into
PARK (P) yet, or into gear for a manual
transmission. When parking uphill, turn your wheels
away from the curb. When parking downhill, turn
your wheels into the curb.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.

5-
5-1
Section 5 Problems on the Road
Here you'll find what to do about some problems that can occur on the road.
5
-2 Hazard Warning Flashers
5
-3 Other Warning Devices
5
-3 Jump Starting
5
-7 Towing Your Vehicle
5
-8 Engine Overheating
5
-10 Cooling System5
-17 Engine Fan Noise
5
-17 If a Tire Goes Flat
5
-18 Changing a Flat Tire
5
-29 Compact Spare Tire (If Equipped)
5
-30 If You're Stuck: In Sand, Mud, Ice or Snow

5-8
Engine Overheating
You will find a coolant temperature gage on your
vehicle's instrument panel. See ªGagesº in the Index.
If Steam Is Coming From Your Engine
CAUTION:
Steam from an overheated engine can burn you
badly, even if you just open the hood. Stay away
from the engine if you see or hear steam coming
from it. Just turn it off and get everyone away
from the vehicle until it cools down. Wait until
there is no sign of steam or coolant before you
open the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch fire. You or
others could be badly burned. Stop your engine if
it overheats, and get out of the vehicle until the
engine is cool.
NOTICE:
If your engine catches fire because you keep
driving with no coolant, your vehicle can be
badly damaged. The costly repairs would not be
covered by your warranty.