2002 CHEVROLET C3500 HD service

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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 or
transmitter resynchronization is necessary. See the
instructions that follow.

If you're still having trouble, see your dealer or a
qualified technician for service.Operation
(UNLOCK): To unlock
the driver's door, press the
UNLOCK button. The
interior lamps will come
on for 40 seconds or until
the ignition is turned on. If
you press the UNLOCK
button again within five
seconds, the passenger
door will unlock.
(LOCK): Press the LOCK button to lock both doors.
The interior lamps will come on for two seconds as soon
as all the doors are closed. If you press the LOCK button
twice the horn will chirp to confirm that the doors have
locked. This will only occur if the transmitter has been
programmed with the ignition off.
If you do not want the horn to chirp as a confirmation
that the doors have locked or unlocked, consult
your dealer.

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To replace the battery, do the following:
1. Insert a thin coin or tool to separate the bottom of the
transmitter from the top.
2. Remove the battery and replace it with a new one,
making sure the positive side of the battery is
facing down.
3. Snap the top and bottom together.
4. Test the operation of the transmitter with your
vehicle. If the transmitter does not work, try
synchronizing the transmitter with the receiver.
Resynchronization
Resynchronization may be necessary due to the security
method used by this system. The transmitter does not
send the same signal twice to the receiver. The receiver
will not respond to a signal it has been sent previously.
This prevents anyone from recording and playing back
the signal from the transmitter.
To resynchronize your transmitter, stand close to your
vehicle and simultaneously press and hold the LOCK
and UNLOCK buttons on the transmitter for at least
five seconds. The door locks should cycle to confirm
synchronization. If the locks do not cycle, see your
dealer for service.
Theft
Vehicle theft is big business, especially in some cities.
Although your vehicle has a number of theft
-deterrent
features, we know that nothing we put on it can make
it impossible to steal. However, there are ways you
can help.

2-11 Key in the Ignition
If you leave your vehicle with the keys inside, it's an
easy target for joy riders or professional thieves
-- so
don't do it.
When you park your vehicle and open the driver's door,
you'll hear a tone reminding you to remove your key
from the ignition and take it with you. Always do this.
Your steering wheel will be locked, and so will your
ignition. If you have an automatic transmission, taking
your key out also locks your transmission. Also
remember to lock the doors.
Parking at Night
Park in a lighted spot, close all windows and lock your
vehicle. Remember to keep your valuables out of sight.
Put them in a storage area, or take them with you.
Parking Lots
Even if you park in a lot where someone will be
watching your vehicle, it's still best to lock it up and
take your keys. But what if you have to leave your
ignition key? What if you have to leave something
valuable in your vehicle?

Put your valuables in a storage area, like your
glove box.
If your vehicle has a remote keyless entry system,
take the transmitter with you.

Lock all the doors except the driver's.
Passlock
Your vehicle is equipped with the Passlock
theft
-deterrent system.
Passlock is a passive theft
-deterrent system. Passlock
enables fuel if the ignition lock cylinder is turned with a
valid key. If a correct key is not used or the ignition lock
cylinder is tampered with, fuel is disabled.
During normal operation, the SECURITY light will
go off approximately five seconds after the key is
turned to RUN.
If the engine stalls and the SECURITY light flashes,
wait until the light stops flashing before trying to restart
the engine. Remember to release the key from START
as soon as the engine starts.
If the engine is running and the SECURITY light comes
on, you will be able to restart the engine if you turn the
engine off. However, your Passlock system is not
working properly and must be serviced by your dealer.
Your vehicle is not protected by Passlock at this time.
You may also want to check the fuses. See ªFuses
and Circuit Breakersº in the Index. See your dealer
for service.

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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. It doesn't lock the steering
wheel like the LOCK position. Use OFF if you must
have your vehicle in motion while the engine is off (for
example, if your vehicle is being pushed).
D (RUN): This is the position for driving.
E (START): This position starts your engine.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.

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Readings in the low warning zone may occur when a
large number of electrical accessories are operating in
the vehicle and the engine is left at an idle for an
extended period. This condition is normal since the
charging system is not able to provide full power at
engine idle. As engine speeds are increased, this
condition should correct itself as higher engine speeds
allow the charging system to create maximum power.
You can only drive for a short time with the reading in
either warning zone. If you must drive, turn off all
unnecessary accessories.
Readings in either warning zone indicate a possible
problem in the electrical system. Have the vehicle
serviced as soon as possible.
Brake System Warning Light
When the ignition is on, the brake system warning light
will come on when you set your parking brake. The light
will stay on if your parking brake doesn't release fully.
If it stays on after your parking brake is fully released, it
means you have a brake problem.Your vehicle's hydraulic brake system is divided into
two parts. If one part isn't working, the other part can
still work and stop you. For good braking, though, you
need both parts working well.
If the warning light comes on, there could be a brake
problem. Have your brake system inspected right away.
United States Canada
This light should come on briefly when you turn the
ignition key to RUN. If it doesn't come on then,
have it fixed so it will be ready to warn you if there's
a problem.

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If the light comes on while you are driving, pull off the
road and stop carefully. You may notice that the pedal is
harder to push. Or, the pedal may go closer to the floor.
It may take longer to stop. If the light is still on, have the
vehicle towed for service. See ªTowing Your Vehicleº in
the Index.
CAUTION:
Your brake system may not be working properly
if the brake system warning light is on. Driving
with the brake system warning light on can lead
to an accident. If the light is still on after you've
pulled off the road and stopped carefully, have
the vehicle towed for service.
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.

2-56 Engine Coolant Temperature Gage
This gage shows the engine
coolant temperature.
It also provides an indicator of how hard your vehicle is
working. During a majority of the operation, the gage
will read 210
F (100
C) or less. If you are pulling a
load or going up hills, it is normal for the temperature to
fluctuate and approach the 260
F (125
C) mark. If the
gage reaches the 260
F (125
C) mark, it indicates that
the cooling system is working beyond its capacity.
See ªEngine Overheatingº in the Index.
Malfunction Indicator Lamp (Service
Engine Soon Light in the United States
or Check Engine Light in Canada)
(Gasoline Engine)
United States Canada
Your vehicle is equipped with a computer which
monitors operation of the fuel, ignition and emission
control systems.

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This system is called OBD II (On-Board
Diagnostics
-Second Generation) and is intended to
assure that emissions are at acceptable levels for the
life of the vehicle, helping to produce a cleaner
environment. The SERVICE ENGINE SOON or
CHECK ENGINE light comes on to indicate that there
is a problem and service is required. Malfunctions often
will be indicated by the system before any problem is
apparent. This may prevent more serious damage to
your vehicle. This system is also designed to assist
your service technician in correctly diagnosing any
malfunction.
NOTICE:
If you keep driving your vehicle with this light
on, after a while, your emission controls may not
work as well, your fuel economy may not be as
good and your engine may not run as smoothly.
This could lead to costly repairs that may not be
covered by your warranty.
NOTICE:
Modifications made to the engine, transmission,
exhaust, intake or fuel system of your vehicle or
the replacement of the original tires with other
than those of the same Tire Performance Criteria
(TPC) can affect your vehicle's emission controls
and may cause the SERVICE ENGINE SOON or
CHECK ENGINE light to come on.
Modifications to these systems could lead to
costly repairs not covered by your warranty. This
may also result in a failure to pass a required
Emission Inspection/Maintenance test.
This light should come on, as a check to show you it is
working, when the ignition is on and the engine is not
running. If the light doesn't come on, have it repaired.
This light will also come on during a malfunction in one
of two ways:

Light Flashing
-- A misfire condition has been
detected. A misfire increases vehicle emissions and
may damage the emission control system on your
vehicle. Dealer or qualified service center diagnosis
and service may be required.