service GMC SONOMA 2002 Owner's Guide

2-80
CAUTION:
Don't keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches fire. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
NOTICE:
Damage to your engine from neglected oil
problems can be costly and is not covered by
your warranty.
Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but readings above the
low pressure zone indicate the normal operating range.
A reading in the low pressure zone may be caused by a
dangerously low oil level or other problems causing low
oil pressure.
Security Light
This light will come on
briefly when you turn the
key toward START. The
light will stay on until the
engine starts.
If the light flashes, the Passlock

system has entered a
tamper mode. If the vehicle fails to start, see ªPasslockº
in the Index.
If the light comes on continuously while driving and
stays on, there may be a problem with the Passlock
system. Your vehicle will not be protected by Passlock,
and you should see your dealer.
Also see ªContent Theft
-Deterrentº in the Index for
additional information regarding the SECURITY light.

2-81 Service Four-Wheel-Drive Warning Light
This light should come on
briefly when you turn on the
ignition, as a check to show
you it is working.
The SERVICE 4WD light comes on to indicate that
there may be a problem with the four
-wheel drive
system and service is required. Malfunctions can be
indicated by the system before any problem is apparent,
which may prevent serious damage to the vehicle. This
system is also designed to assist your service technician
in correctly diagnosing a malfunction.
Check Gages Light
If this light comes on and
stays on while you are
driving, check your coolant
temperature and engine oil
pressure gages to see if they
are in the warning zones.

3-13
To adjust balance or fade to the middle position, select
BAL or FAD. Then press and hold AUDIO for more
than two seconds until you hear a beep. L and a zero or
F and a zero will appear on the display. To adjust both
tone controls and both speaker controls to the middle
position, end out of audio mode by pressing the AUDIO
button until the display goes blank. Then press and hold
AUDIO for more than two seconds until you hear a
beep. CEN will appear on the display.
Radio Messages
CAL (Calibrated): Your audio system has been
calibrated for your vehicle from the factory. If CAL
appears on the display it means that your radio has not
been configured properly for your vehicle and must be
returned to the dealership for service.
LOC (Locked): This message is displayed when the
Theftlock

system has locked up. Your vehicle must be
returned to the dealership for service.
AM-FM Stereo with Cassette Tape Player
(If Equipped)
Playing the Radio
Power: Turn the VOLUME knob to turn the system on
and off.
VOLUME: Turn this knob clockwise to increase
volume. Turn it counterclockwise to decrease volume.
RECALL: Press this knob to display the station being
played or to display the clock. Clock display is available
with the ignition turned off.

3-31
INFO (Information): If the current station has a
message, the information symbol will appear on the
display. These text messages are from the RDS
broadcaster to the listening public and may be general
information such as artist and song title, call in phone
numbers, etc. Press this button to see the message. If the
whole message does not appear on the display, parts of
the message will appear every three seconds until the
message is completed. To scroll through the message at
your own speed, press the INFO button again for less
than one second. A new group of words will appear on
the display. Once the complete message has been
displayed, the information symbol will disappear from
the display until another new message is received. The
old message can be displayed by pressing the INFO
button until a new message is received or a different
station is tuned to.
TRAF (Traffic): Press this button to receive traffic
announcements. If the current station does not broadcast
traffic announcements, the radio will seek to a station
that does. The traffic symbol will flash on the display.
When the radio finds a station that broadcasts traffic
announcements, it will stop. If no station is found, NO
TRAF will appear on the display.Your radio can be programmed to interrupt the playback
of a CD or FM station by enabling the traffic interrupt
feature. Press the TRAF button once to seek to an RDS
station that supports the traffic interrupt feature if the
current station does not. The traffic symbol will flash on
the display when seeking for a station that supports
traffic interrupt. When the traffic interrupt feature is on,
TRAF will appear on the display.
When a traffic announcement comes on the current radio
station, you will hear it, even if the volume is muted or a
compact disc is playing. The traffic symbol and
TRAFFIC will appear on the display while the traffic
announcement plays. If the compact disc player was
being used, the compact disc will stay in the player and
resume play at the point where it stopped.
Radio Messages
CAL ERR (Calibration Error): This message is
displayed when the radio has not been calibrated
properly for the vehicle. You must return to the
dealership for service.
LOCKED: This message is displayed when the
THEFTLOCK

system has locked up. You must return
to the dealership for service.
If any error occurs repeatedly or if an error can't be
corrected, contact your dealer.

3-39
INFO (Information): If the current station has a
message, the information icon will appear on the
display. These text messages are from the RDS
broadcaster to the listening public and may be general
information such as artist and song title, call in phone
numbers, etc. Press this button to see the message. If the
whole message does not appear on the display, parts of
the message will appear every three seconds until the
message is completed. To scroll through the message at
your own speed, press the INFO button again for less
than one second. A new group of words will appear on
the display. Once the complete message has been
displayed, the information icon will disappear from the
display until another new message is received. The old
message can be displayed by pressing the INFO button
until a new message is received or a different station is
tuned to.
TRAF (Traffic): Press this button to receive traffic
announcements. If the current station does not broadcast
traffic announcements, the radio will seek to a station
that does. The traffic symbol will flash on the display.
When the radio finds a station that broadcasts traffic
announcements, it will stop. If no station is found, NO
TRAF will appear on the display.Your radio can be programmed to interrupt the playback
of a cassette tape, CD or FM radio by enabling the
traffic interrupt feature. Press the TRAF button once to
seek to an RDS station that supports the traffic interrupt
feature if the current station does not. The traffic symbol
will flash on the display when seeking for a station that
supports traffic interrupt. When the traffic interrupt
feature is on, TRAF will appear on the display.
When a traffic announcement comes on the current radio
station, you will hear it, even if the volume is muted or a
cassette tape or compact disc is playing. The traffic
symbol and TRAFFIC will appear on the display while
the traffic announcement plays. If the cassette tape or
compact disc player was being used, the tape or compact
disc will stay in the player and resume play at the point
where it stopped.
Radio Messages
CAL ERR (Calibration Error): This message is
displayed when the radio has not been calibrated
properly for the vehicle. You must return to the
dealership for service.
LOCKED: This message is displayed when the
THEFTLOCK

system has locked up. You must return
to the dealership for service.

3-63
3. Press and hold the TAPE AUX button for five
seconds. The tape symbol on the display will flash
for two seconds.
4. Insert the scrubbing action cleaning cassette.
5. Eject the cleaning cassette after the manufacturer's
recommended cleaning time.
When the cleaning cassette has been ejected, the broken
tape detection feature is active again.
You may also choose a non
-scrubbing action, wet-type
cleaner which uses a cassette with a fabric belt to clean
the tape head. This type of cleaning cassette will not
eject on its own. A non
-scrubbing action cleaner may
not clean as thoroughly as the scrubbing type cleaner.
The use of a non
-scrubbing action, dry-type cleaning
cassette is not recommended.
After you clean the player, press and hold the EJECT
button for five seconds to reset the CLN indicator. The
radio will display
--- to show the indicator was reset.
Cassettes are subject to wear and the sound quality
may degrade over time. Always make sure the cassette
tape is in good condition before you have your tape
player serviced.
Care of Your Remote Cassette Tape Player
A tape player that is not cleaned regularly can cause
reduced sound quality, ruined cassettes or a damaged
mechanism. Cassette tapes should be stored in their
cases away from contaminants, direct sunlight and
extreme heat. If they aren't, they may not operate
properly or may cause failure of the tape player.
Your remote tape player should be cleaned regularly
after every 50 hours of use. Your radio may display
CLN to indicate that you have used your remote cassette
tape player for 50 hours without resetting the tape clean
timer. If this message appears on the display, your
remote cassette tape player needs to be cleaned. It will
still play tapes, but you should clean it as soon as
possible to prevent damage to your tapes and player.
The recommended cleaning method for your remote
cassette tape player is the use of a scrubbing action,
non
-abrasive cleaning cassette with pads which scrub
the tape head as the hubs of the cleaner cassette turn.
The recommended cleaning cassette is available through
your dealer (GM Part No. 12344789).

4-15 Before You Go Off-Roading
There are some things to do before you go out.
For example, be sure to have all necessary maintenance
and service work done. Check to make sure all
underbody shields (if so equipped) are properly
attached. Be sure you read all the information about
your four
-wheel-drive vehicle in this manual. Is there
enough fuel? Is the spare tire fully inflated? Are the
fluid levels up where they should be? What are the local
laws that apply to off
-roading where you'll be driving?
If you don't know, you should check with law
enforcement people in the area. Will you be on
someone's private land? If so, be sure to get the
necessary permission.
Loading Your Vehicle for Off-Road Driving
There are some important things to remember about
how to load your vehicle.

The heaviest things should be on the load floor and
forward of your rear axle. Put heavier items as far
forward as you can.

Be sure the load is secured properly, so driving on
the off
-road terrain doesn't toss things around.
CAUTION:

Cargo on the load floor piled higher than
the seatbacks can be thrown forward
during a sudden stop. You or your
passengers could be injured. Keep cargo
below the top of the seatbacks.

Unsecured cargo on the load floor can be
tossed about when driving over rough
terrain. You or your passengers can be
struck by flying objects. Secure the cargo
properly.

Heavy loads on the roof raise the vehicle's
center of gravity, making it more likely to
roll over. You can be seriously or fatally
injured if the vehicle rolls over. Put heavy
loads inside the cargo area, not on the roof.
Keep cargo in the cargo area as far forward
and low as possible.
You'll find other important information in this manual.
See ªVehicle Loading,º ªLuggage Carrierº and ªTiresº
in the Index.

4-27 After Off-Road Driving
Remove any brush or debris that has collected on the
underbody, chassis or under the hood. These
accumulations can be a fire hazard.
After operation in mud or sand, have the brake linings
cleaned and checked. These substances can cause
glazing and uneven braking. Check the body structure,
steering, suspension, wheels, tires and exhaust system
for damage. Also, check the fuel lines and cooling
system for any leakage.
Your vehicle will require more frequent service due to
off
-road use. Refer to the Maintenance Schedule for
additional information.
Driving at Night
Night driving is more dangerous than day driving.
One reason is that some drivers are likely to be
impaired
-- by alcohol or drugs, with night vision
problems, or by fatigue.

4-34
Once you are moving on the freeway, make certain you
allow a reasonable following distance. Expect to move
slightly slower at night.
When you want to leave the freeway, move to the proper
lane well in advance. If you miss your exit, do not,
under any circumstances, stop and back up. Drive on to
the next exit.
The exit ramp can be curved, sometimes quite sharply.
The exit speed is usually posted.
Reduce your speed according to your speedometer, not
to your sense of motion. After driving for any distance
at higher speeds, you may tend to think you are going
slower than you actually are.
Before Leaving on a Long Trip
Make sure you're ready. Try to be well rested. If you
must start when you're not fresh
-- such as after a day's
work
-- don't plan to make too many miles that first part
of the journey. Wear comfortable clothing and shoes you
can easily drive in.Is your vehicle ready for a long trip? If you keep it
serviced and maintained, it's ready to go. If it needs
service, have it done before starting out. Of course,
you'll find experienced and able service experts in GM
dealerships all across North America. They'll be ready
and willing to help if you need it.
Here are some things you can check before a trip:

Windshield Washer Fluid: Is the reservoir full? Are
all windows clean inside and outside?

Wiper Blades: Are they in good shape?

Fuel, Engine Oil, Other Fluids: Have you checked
all levels?

Lamps: Are they all working? Are the lenses clean?

Tires: They are vitally important to a safe,
trouble
-free trip. Is the tread good enough for
long
-distance driving? Are the tires all inflated to the
recommended pressure?

Weather Forecasts: What's the weather outlook
along your route? Should you delay your trip a short
time to avoid a major storm system?

Maps: Do you have up
-to-date maps?

4-35
Highway Hypnosis
Is there actually such a condition as ªhighway
hypnosisº? Or is it just plain falling asleep at the wheel?
Call it highway hypnosis, lack of awareness, or
whatever.
There is something about an easy stretch of road with
the same scenery, along with the hum of the tires on the
road, the drone of the engine, and the rush of the wind
against the vehicle that can make you sleepy. Don't let it
happen to you! If it does, your vehicle can leave the
road in less than a second, and you could crash and
be injured.
What can you do about highway hypnosis? First, be
aware that it can happen.
Then here are some tips:

Make sure your vehicle is well ventilated, with a
comfortably cool interior.

Keep your eyes moving. Scan the road ahead and to
the sides. Check your mirrors and your instruments
frequently.

If you get sleepy, pull off the road into a rest, service
or parking area and take a nap, get some exercise, or
both. For safety, treat drowsiness on the highway as
an emergency.
Hill and Mountain Roads
Driving on steep hills or mountains is different from
driving in flat or rolling terrain.