Changes or modifications to this system by other than
an authorized service facility could void authorization
to use this equipment.
At times you may notice a decrease in range. This is
normal for any remote keyless entry system. If the
transmitter does not work or if you have to stand closer
to your vehicle for the transmitter to work, try this:
•Check the distance. You may be too far from your
vehicle. You may need to stand closer during
rainy or snowy weather.
•Check the location. Other vehicles or objects may be
blocking the signal. Take a few steps to the left or
right, hold the transmitter higher, and try again.
•Check to determine if battery replacement is
necessary. See“Battery Replacement”under
Remote Keyless Entry System Operation
on page 2-5.
•If you are still having trouble, see your dealer or
a qualified technician for service.
Remote Keyless Entry System
Operation
If your vehicle has this feature, you can lock and unlock
your doors from about 3 feet (1 m) up to 30 feet (9 m)
away using the remote keyless entry transmitter supplied
with your vehicle.
UNLOCK:When you
press UNLOCK, the
driver’s door will unlock
automatically, the parking
lamps willflash and the
interior lights will go on.
If you press UNLOCK again within three seconds, the
remaining doors will unlock, the parking lamps willflash
and the interior lights will go on.
LOCK:Press LOCK to lock all the doors. Press LOCK
again within three seconds and the horn will chirp.
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2003 - Sonoma OM
L(Panic Alarm):When the panic button with the
horn symbol on the keyless entry transmitter is pressed,
the horn will sound and the headlamps and taillamps
willflash for up to 30 seconds. This can be turned off by
pressing the panic button again, waiting for 30 seconds,
or starting the vehicle.
Matching Transmitter(s) to Your
Vehicle
Each remote keyless entry transmitter is coded to
prevent another transmitter from unlocking your vehicle.
If a transmitter is lost or stolen, a replacement can
be purchased through your dealer. Remember to bring
any remaining transmitters with you when you go to
your dealer. When the dealer matches the replacement
transmitter to your vehicle, any remaining transmitters
must also be matched. Once your dealer has coded the
new transmitter, the lost transmitter will not unlock
your vehicle. Each vehicle can have a maximum of four
transmitters matched to it.
Battery Replacement
Under normal use, the battery in your remote keyless
entry transmitter should last about two years.
You can tell the battery is weak if the transmitter won’t
work at the normal range in any location. If you have
to get close to your vehicle before the transmitter works,
it’s probably time to change the battery.
Notice:When replacing the battery, use care not to
touch any of the circuitry. Static from your body
transferred to these surfaces may damage the
transmitter.
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2003 - Sonoma OM
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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2003 - Sonoma OM
Service............................................................5-3
Doing Your Own Service Work.........................5-3
Adding Equipment to the Outside of
Your Vehicle..............................................5-4
Fuel................................................................5-4
Gasoline Octane............................................5-4
Gasoline Specifications....................................5-5
California Fuel...............................................5-5
Additives.......................................................5-5
Fuels in Foreign Countries...............................5-6
Filling Your Tank............................................5-6
Filling a Portable Fuel Container.......................5-8
Checking Things Under
the Hood......................................................5-8
Hood Release................................................5-9
Engine Compartment Overview.......................5-10
Engine Oil...................................................5-13
Engine Air Cleaner/Filter................................5-18
Automatic Transmission Fluid
.........................5-20
Manual Transmission Fluid
.............................5-23
Hydraulic Clutch
...........................................5-24Engine Coolant.............................................5-25
Radiator Pressure Cap..................................5-27
Engine Overheating.......................................5-28
Cooling System............................................5-30
Engine Fan Noise.........................................5-36
Power Steering Fluid.....................................5-37
Windshield Washer Fluid................................5-38
Brakes........................................................5-39
Battery........................................................5-42
Jump Starting...............................................5-43
Rear Axle.......................................................5-47
Four-Wheel Drive............................................5-48
Front Axle......................................................5-49
Bulb Replacement..........................................5-50
Halogen Bulbs..............................................5-50
Headlamps..................................................5-50
One-Piece Front Turn Signal Lamps................5-52
Two-Piece Front Turn Signal Lamps................5-53
Center High-Mounted Stoplamp (CHMSL).........5-54
Taillamps.....................................................5-55
Replacement Bulbs.......................................5-55
Section 5 Service and Appearance Care
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2003 - Sonoma OM
Replacing Brake System Parts
The braking system on a vehicle is complex. Its many
parts have to be of top quality and work well together if
the vehicle is to have really good braking. Your vehicle
was designed and tested with top-quality GM brake parts.
When you replace parts of your braking system—for
example, when your brake linings wear down and you
need new ones put in—be sure you get new approved
GM replacement parts. If you don’t, your brakes may no
longer work properly. For example, if someone puts in
brake linings that are wrong for your vehicle, the balance
between your front and rear brakes can change—for the
worse. The braking performance you’ve come to expect
can change in many other ways if someone puts in the
wrong replacement brake parts.
Battery
Your new vehicle comes with a maintenance free
ACDelco®battery. When it’s time for a new battery, get
one that has the replacement number shown on the
original battery’s label. We recommend an ACDelco
®
battery. SeeEngine Compartment Overview on
page 5-10for battery location.
Warning:Battery posts, terminals and related
accessories contain lead and lead compounds,
chemicals known to the State of California to cause
cancer and reproductive harm. Wash hands after
handling.
Vehicle Storage
If you’re not going to drive your vehicle for 25 days or
more, remove the black, negative (−) cable from
the battery. This will help keep your battery from
running down.
{CAUTION:
Batteries have acid that can burn you and gas
that can explode. You can be badly hurt if you
aren’t careful. See“Jump Starting”next for
tips on working around a battery without
getting hurt.
Contact your dealer to learn how to prepare your
vehicle for longer storage periods.
Also, for your audio system, seeTheft-Deterrent
Feature (Non-RDS Radios) on page 3-67or
Theft-Deterrent Feature (RDS Radios) on page 3-67.
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