2001 GMC SONOMA tow

2-80 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.
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.

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 heating system
control panel controls 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.
Mode Knob
The right knob on the control panel allows you to
choose the direction of air delivery.
OFF: This setting turns the system off. Some outside
air will still enter the vehicle whenever the vehicle is
moving forward. If the air entering your vehicle is
warmer than desired, turn the temperature knob fully
counterclockwise and turn the mode knob to VENT.
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 heater
floor outlets as well as the instrument panel outlets.
HEATER: This setting directs most of the
warmed air through the heater floor outlets and some air
through the windshield defroster outlets.

3-3
BLEND: Airflow is divided equally between the
heater floor outlet and the windshield defroster outlets.
DEFROST: This setting directs most air through
the windshield defroster outlets and some through the
heater outlets.
Optional Climate Control System
Fan Control
The knob on the left side of the heating system
control panel operates 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.
Mode Knob
The right knob on the control panel allows you to
choose the direction of air delivery.
OFF: This setting turns the system off. Some outside
air will still enter the vehicle whenever the vehicle is
moving forward.
MAX A/C: This setting provides maximum cooling
with the least amount of work. MAX A/C recirculates
much of the air inside your vehicle so it cools quickly.
This setting directs most of the air through the
instrument panel vents and a small amount through the
floor vents.
A/C: This setting cools the air entering your vehicle and
directs most of the air through the instrument panel
vents and a small amount through the floor vents.

3-5 Heating
The heater works best if you keep your windows closed
while using it. On cold days, use HEATER 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.
Defogging and Defrosting
On cool, humid days, use BLEND to keep the
windshield and side windows clear.
Use DEFROST to remove fog or ice from the
windshield quickly in extreme humid or cold conditions.
Turn the temperature knob clockwise and turn the fan
control toward high.
If you have the heated outside mirror feature, you can
use it to defog or defrost your outside mirrors. For more
information, see ªHeated Outside Mirrorsº in the Index.
Ventilation System
For mild outside temperatures when little heating or
cooling is needed, use VENT to direct outside air
through your vehicle. Airflow is through the instrument
panel outlets.
Your vehicle's ventilation system supplies outside air to
the inside of your vehicle when it is moving. When the
vehicle is not moving, you can get outside air to flow
through by selecting any mode and any fan speed.
You will find air outlets in the center and on the sides of
your instrument panel.

4-
4-1
Section 4 Your Driving and the Road
Here you'll find information about driving on different kinds of roads and in varying weather conditions. We've also
included many other useful tips on driving.
4
-2 Defensive Driving
4
-3 Drunken Driving
4
-6 Control of a Vehicle
4
-6 Braking
4
-9 Steering
4
-11 Off-Road Recovery
4
-11 Passing
4
-13 Loss of Control
4
-14 Off-Road Driving with Your
Four
-Wheel-Drive Vehicle
4
-26 Driving at Night4
-28 Driving in Rain and on Wet Roads
4
-31 City Driving
4
-32 Freeway Driving
4
-33 Before Leaving on a Long Trip
4
-34 Highway Hypnosis
4
-34 Hill and Mountain Roads
4
-36 Winter Driving
4
-39 Recreational Vehicle Towing
4
-40 Loading Your Vehicle
4
-45 Pickup Conversion to Chassis Cab
4
-46 Towing a Trailer

4-39
CAUTION:
Snow can trap exhaust gases under your vehicle.
This can cause deadly CO (carbon monoxide) gas
to get inside. CO could overcome you and kill
you. You can't see it or smell it, so you might not
know it is in your vehicle. Clear away snow from
around the base of your vehicle, especially any
that is blocking your exhaust pipe. And check
around again from time to time to be sure snow
doesn't collect there.
Open a window just a little on the side of the
vehicle that's away from the wind. This will help
keep CO out.
Run your engine only as long as you must. This saves
fuel. When you run the engine, make it go a little faster
than just idle. That is, push the accelerator slightly. This
uses less fuel for the heat that you get and it keeps the
battery charged. You will need a well
-charged battery to
restart the vehicle, and possibly for signaling later on
with your headlamps. Let the heater run for a while.Then, shut the engine off and close the window almost
all the way to preserve the heat. Start the engine again
and repeat this only when you feel really uncomfortable
from the cold. But do it as little as possible. Preserve the
fuel as long as you can. To help keep warm, you can get
out of the vehicle and do some fairly vigorous exercises
every half hour or so until help comes.
Recreational Vehicle Towing
Your vehicle should not be towed with all four wheels
on the ground. Your transmission has no provision for
internal lubrication while being towed. To properly tow
your vehicle, it should be placed on a platform trailer
with all four wheels off the ground. Towing with all four
wheels on the ground should be avoided.
In rare cases when it's unavoidable and your vehicle
must be towed with all four wheels on the ground, the
propeller shaft to axle yoke orientation should be
marked and the propeller shaft removed following the
applicable service manual removal/installation
procedure. See ªService and Owner Publicationsº in
the Index.

4-40
Dust or dirt can enter the back of the transmission
through the opening created by removing the propeller
shaft if proper protection is not provided. Also, check
the transmission fluid level before driving the vehicle.
When towing your vehicle, turn the ignition to OFF.
To prevent your battery from draining while towing,
remove the RDO BATT and CLSTR fuses from the
instrument panel fuse block. Be sure to replace the fuse
when you reach your destination. See ªFuses and Circuit
Breakersº in the Index.
Be sure to use the proper towing equipment designed for
recreational vehicle towing. Follow the instructions for
the towing equipment.Loading Your Vehicle
The Certification/Tire label is found on the driver's door
edge, above the door latch. The label shows the size of
your original tires and the inflation pressures needed to
obtain the gross weight capacity of your vehicle. This is
called the Gross Vehicle Weight Rating (GVWR). The
GVWR includes the weight of the vehicle, all occupants,
fuel, cargo and trailer tongue weight, if pulling a trailer.

4-45
You must weigh any accessories, trailer hitches or other
equipment you add to your vehicle. Then, subtract this
extra weight from the CWR. This extra weight may
shorten the center of gravity zone for your vehicle.
Your dealer can help you with this.
If your slide
-in camper and its load weigh less than the
CWR, the center of gravity zone for your vehicle may
be larger.
Your dealer can help you make a good vehicle
-camper
match. He'll also help you determine your CWR.
Secure loose items to prevent weight shifts that could
affect the balance of your vehicle. When the truck camper
is loaded, drive to a scale and weigh on the front and on
the rear wheels separately to determine axle loads.
Individual axle loads should not exceed either of the
Gross Axle Weight Ratings (GAWR). The total of the
axle loads should not exceed the Gross Vehicle Weight
Rating (GVWR). These ratings are given on the vehicle
certification label that is located on the rear of the
passenger's door. If weight ratings are exceeded, move
or remove items to bring all weights below the ratings.
If you want more information on curb weights, cargo
weights, cargo weight rating and the correct center of
gravity zone for your vehicle, your dealer can help you.
Just ask for a copy of ªConsumer Information,
Truck
-Camper Loading.º
Trailer Recommendations
You must subtract your hitch load from the CWR
for your vehicle. Weigh your vehicle with your trailer
attached, so that you won't go over the GVWR or
the GAWR.
You'll get the best performance if you spread out the
weight of your load the right way, and if you choose the
correct hitch and trailer brakes.
For more information, see ªTowing a Trailerº later in
this section.
Pickup Conversion to Chassis Cab
General Motors is aware that some vehicle owners may
consider having the pickup box removed and a
commercial or recreational body installed. However, we
recommend that conversions of this type not be done to
pickups. Owners should be aware that, as manufactured,
there are differences between a chassis cab and a pickup
with the box removed which may affect vehicle safety.
For specific information on this pickup, contact the
GM Customer Assistance Office for your area. See the
ªWarranty and Owner Assistanceº booklet for Customer
Assistance Office.