2003 GMC SONOMA tow

Starting and Operating Your
Vehicle
New Vehicle Break-In
Notice:Your vehicle doesn’t need an elaborate
“break-in.”But it will perform better in the long run
if you follow these guidelines:
Keep your speed at 55 mph (88 km/h) or less for
the first 500 miles (805 km).
•Don’t drive at any one speed — fast or slow — for
the first 500 miles (805 km). Don’t make
full-throttle starts.
•Avoid making hard stops for the first 200 miles
(322 km) or so. During this time your new brake
linings aren’t yet broken in. Hard stops with new
linings can mean premature wear and earlier
replacement. Follow this breaking-in guideline
every time you get new brake linings.
•Don’t tow a trailer during break-in.
See “Towing a Trailer” in the Index for
more information.
Ignition Positions
With the key in the ignition, you can turn it tofive
different positions.
Notice:Don’t operate accessories in the
ACCESSORY position for long periods of time.
Prolonged operation of accessories in the
ACCESSORY position could drain your battery and
prevent you from starting your vehicle.
A (ACCESSORY):This position lets you use things like
the radio and the windshield wipers when the engine
is off. Push in the key and turn it toward you. Your
steering wheel will remain locked, just as it was before
you inserted the key.
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{CAUTION:
On manual transmission vehicles, turning the
key to LOCK will lock the steering column and
result in a loss of ability to steer the vehicle.
This could cause a collision. If you need to
turn the engine off while the vehicle is moving,
turn the key only to OFF. Don’t press the key
release button while the vehicle is moving.
Notice:If your key seems stuck in LOCK and you
can’t turn it, be sure you are using the correct key;
if so, is it all the way in? If it is, then turn the steering
wheel left and right while you turn the key hard. Turn
the key only with your hand. Using a tool to force it
could break the key or the ignition switch. If none of
this works, then your vehicle needs service.
B (LOCK):This position locks your ignition, steering
wheel and transmission. It’s a theft-deterrent feature.
You will only be able to remove your key when the
ignition is turned to LOCK.C (OFF):This position lets you turn off the engine but
still turn the steering wheel. Use OFF if you must
have your vehicle in motion while the engine is off
(for example, if your vehicle is being towed).
D (RUN):This is the position for driving.
E (START):This position starts your engine.
Key Release Button
The key cannot be
removed from the ignition
of manual transmission
vehicles unless the
key release button is
pressed.
To remove the key, turn the ignition switch to OFF.
Then turn the key to LOCK while pressing the key
release button. Pull the key straight out.
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Automatic Transmission Operation
Your automatic transmission has a shift lever on the
steering column.
There are several different positions for your shift lever.
It features an electronic shift position indicator within
the instrument cluster. This display must be powered
anytime the shift lever is capable of being moved out of
PARK (P). This means that if your key is in OFF, but
not locked, there will be a small current drain on
your battery which could discharge your battery over a
period of time. If you need to leave your key in the
ignition in OFF for an extended period, it is
recommended that you disconnect the battery cable
from the battery to prevent discharging your battery.PARK (P):This position locks your rear wheels. It’s the
best position to use when you start your engine because
your vehicle can’t move easily.
{CAUTION:
It is dangerous to get out of your vehicle if the
shift lever is not fully in PARK (P) with the
parking brakefirmly set. Your vehicle can roll.
Don’t leave your vehicle when the engine is
running unless you have to. If you have left the
engine running, the vehicle can move suddenly.
You or others could be injured. To be sure your
vehicle won’t move, even when you’re on fairly
level ground, always set your parking brake and
move the shift lever to PARK (P). See“Shifting
Into Park (P)”in the Index. If you’re pulling a
trailer, see“Towing a Trailer”in the Index.
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DRIVE (D):This position is for normal driving.
If you need more power for passing, and you’re:
•Going less than about 35 mph (55 km/h), push your
accelerator pedal about halfway down.
•Going about 35 mph (55 km/h) or more, push the
accelerator all the way down.
You’ll shift down to the next gear and have more power.
DRIVE (D) should not be used when towing a trailer,
carrying a heavy load, driving on steep hills, or for
off-road driving. Select THIRD (3) when operating the
vehicle under any of these conditions.
THIRD (3):This position is also used for normal driving,
however, it offers more power and lower fuel economy
than DRIVE (D). You should use THIRD (3) when towing
a trailer, carrying a heavy load, driving on steep hills
or winding roads or for off-road driving.
SECOND (2):This position gives you more power but
lower fuel economy than THIRD (3). You can use
SECOND (2) on hills. It can help control your speed as
you go down steep mountain roads, but then you
would also want to use your brakes off and on. You can
also use SECOND (2) for starting your vehicle from a
stop on slippery road surfaces.FIRST (1):This position gives you even more power
but lower fuel economy than SECOND (2). You can use
it on very steep hills, or in deep snow or mud. If the
shift lever is put in FIRST (1) while the vehicle is moving
forward, the transmission won’t shift into FIRST (1)
until the vehicle is going slowly enough.
Notice:If your wheels won’t turn, don’t try to drive.
This might happen if you were stuck in very deep
sand or mud or were up against a solid object. You
could damage your transmission. Also, if you
stop when going uphill, don’t hold your vehicle there
with only the accelerator pedal. This could overheat
and damage the transmission. Use your brakes
or shift into PARK (P) to hold your vehicle in
position on a hill.
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Parking Brake
The parking brake is located near the bottom of the
instrument panel on the driver’s side of the vehicle.
To set the parking brake, hold the regular brake pedal
down with your right foot. Push down the parking
brake pedal with your left foot. If the ignition is on, the
brake system warning light will come on.
Notice:Driving with the parking brake on can
cause your rear brakes to overheat. You may have
to replace them, and you could also damage
other parts of your vehicle.
To release the parking brake, hold the regular brake
pedal down. Pull the BRAKE RELEASE lever fully.
It is located on the bottom off the instrument panel on
the driver’s side of the vehicle.If you are towing a trailer and you must park on a hill,
seeTowing a Trailer on page 4-51. That section
shows what to dofirst to keep the trailer from moving.
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Shifting Into Park (P)
{CAUTION:
It can be dangerous to get out of your vehicle
if the shift lever is not fully in PARK (P) with
the parking brakefirmly set. Your vehicle can
roll. If you have left the engine running, the
vehicle can move suddenly. You or others
could be injured. To be sure your vehicle won’t
move, even when you’re on fairly level ground,
use the steps that follow. If you’re pulling a
trailer, see“Towing a Trailer”in the Index.
1. Hold the brake pedal down with your right foot and
set the parking brake.2. Move the shift lever into PARK (P) position like this:
•Pull the lever toward you.
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•Move the lever up as far as it will go.
3. Turn the ignition key to LOCK.
4. Remove the key and take it with you. If you can
leave your vehicle with the key, your vehicle is in
PARK (P).
Leaving Your Vehicle With the Engine
Running
{CAUTION:
It can be dangerous to leave your vehicle with
the engine running. Your vehicle could move
suddenly if the shift lever is not fully in
PARK (P) with the parking brakefirmly set.
And, if you leave the vehicle with the engine
running, it could overheat and even catchfire.
You or others could be injured. Don’t leave
your vehicle with the engine running.
If you have to leave your vehicle with the engine
running, be sure your vehicle is in PARK (P) and your
parking brake isfirmly set before you leave it. After
you’ve moved the shift lever into PARK (P), hold
the regular brake pedal down. Then, see if you can
move the shift lever away from PARK (P) withoutfirst
pulling it toward you. If you can, it means that the
shift lever wasn’t fully locked into PARK (P).
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Parking Your Vehicle
If you have a manual transmission, before you get out
of your vehicle, move the shift lever into REVERSE (R),
andfirmly apply the parking brake. Once the shift
lever has been placed into REVERSE (R) with the clutch
pedal pressed in, you can turn the ignition key to
OFF, remove the key and release the clutch.
If you are parking on a hill, or if your vehicle is pulling a
trailer, seeTowing a Trailer on page 4-51.
Parking Over Things That Burn
{CAUTION:
Things that can burn could touch hot exhaust
parts under your vehicle and ignite. Don’t park
over papers, leaves, dry grass or other things
that can burn.
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