2001 GMC SIERRA AC system

2-11
LOCK: Pressing this button once will lock all of the
doors. Press LOCK again within three seconds and the
horn will chirp.
Operating the keyless entry transmitter may interact
with the theft
-deterrent system. See ªContent-Theft
Deterrentº in the Index.
Remote Panic Alarm
When the button with the horn symbol on the keyless
entry transmitter is pressed, the horn will sound and the
headlamps and taillamps will flash for up to 30 seconds.
This can be turned off by pressing the horn 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 only 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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To replace the battery in the keyless entry transmitter, do
the following:
1. Insert a dime in the slot between the covers of the
transmitter housing near the key ring hole. Remove
the bottom by twisting the dime.
2. Remove and replace the battery with a three
-volt
CR2032 or equivalent battery, positive (+) side up.
3. Align the covers and snap them together.
4. Resynchronize the transmitter.
5. Check the operation of the transmitter.
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 that 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 press and hold the LOCK and UNLOCK
buttons on the transmitter at the same time for
seven seconds. The door locks should cycle to confirm
synchronization. If the locks do not cycle, see your
dealer for service.

2-15
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.
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 chime reminding you to remove your key
from the ignition and take it with you. Always do this.
If you have a manual transmission, your steering wheel
will be locked, and so will your ignition. If you have an
automatic transmission, your ignition and transmission
will be locked. Also remember to lock the doors.
If the key is in the ignition, with any door open, and you
try to lock your doors with the power door locks, the
driver's door will not stay locked. This will help to keep
you from locking your keys in the vehicle.
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.

Valuables can be locked in the center floor console.

If your vehicle has a remote keyless entry system,
take the transmitter with you.

Lock all the doors except the driver's.

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Content Theft-Deterrent
(If Equipped)
Your vehicle may be equipped with a Content
Theft
-Deterrent alarm system.
With this system, the
SECURITY message will
flash as you open the door
(if your ignition is off).
This message reminds you to activate the theft
-deterrent
system. Here's how to do it:
1. Open the door.
2. Lock the door with the power door lock switch or the
remote keyless entry transmitter. The SECURITY
message should come on and stay on. If using the
remote keyless entry transmitter, the door does not
need to be open.
3. Close all doors. The SECURITY message should go
off after approximately 15 seconds. The alarm is not
armed until the SECURITY message goes off.If a door is opened without the key or the remote keyless
entry transmitter, the alarm will go off. Your vehicle's
headlamps will flash and the horn will sound for about
two minutes, then will turn off to save the battery power.
Remember, the theft
-deterrent system won't activate if
you lock the doors with a key or use the manual door
lock. It activates only if you use a power door lock
switch with the door open, or with the remote keyless
entry transmitter. You should also remember that you
can start your vehicle with the correct ignition key if the
alarm has been set off.
Here's how to avoid setting off the alarm by accident:

If you don't want to activate the theft
-deterrent
system, the vehicle should be locked with the door
key after the doors are closed.

Always unlock a door with a key, or use the remote
keyless entry transmitter. Unlocking a door any other
way will set off the alarm if the system has been armed.
If you set off the alarm by accident, unlock any door
with the key. You can also turn off the alarm by pressing
UNLOCK on the remote keyless entry transmitter or by
placing the key in the ignition and turning it to START.

2-17
Testing the Alarm
The alarm can be tested by following these steps:
1. From inside the vehicle, lower the driver's window
and open the driver's door.
2. Activate the system by locking the doors with the
power door lock switch while the door is open, or
with the remote keyless entry transmitter.
3. Get out of the vehicle, close the door and wait for the
SECURITY message to go out.
4. Then reach in through the window, unlock the door
with the manual door lock and open the door.
This should set off the alarm.
If the alarm does not sound when it should but the
vehicle's headlamps flash, check to see if the horn
works. The horn fuse may be blown. To replace the fuse,
see ªFuses and Circuit Breakersº in the Index.
If the alarm does not sound or the vehicle's headlamps
do not flash, the vehicle should be serviced by an
authorized service center.
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.
If the engine stalls and the SECURITY message 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 message
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 fuse (see ªFuses and
Circuit Breakersº in the Index). See your dealer
for service.
In an emergency, call the GM Roadside Assistance
Center. See ªRoadside Assistanceº in the Index.

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You can choose among four driving settings:
2HI: This setting is used for driving in most street and
highway situations. Your front axle is not engaged in
two
-wheel drive. This setting also provides the best
fuel economy.
AUTO 4WD: This setting is ideal for use when road
conditions are variable. When driving your vehicle in
AUTO 4WD, the front axle is engaged, but the vehicle's
power is sent to the rear wheels. When the vehicle
senses a loss of traction, the system will automatically
engage four
-wheel drive. Driving in this mode results in
slightly lower fuel economy than 2HI.4HI: Use 4HI when you need extra traction, such as on
snowy or icy roads or in most off
-road situations. This
setting also engages your front axle to help drive your
vehicle. This is the best setting to use when plowing snow.
4LO: This setting also engages your front axle and
delivers extra torque. You may never need 4LO. It sends
maximum power to all four wheels. You might choose
4LO if you are driving off
-road in deep sand, deep mud,
deep snow and climbing or descending steep hills.
CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the transmission
is in PARK (P). You or someone else could be
seriously injured. Be sure to set the parking
brake before placing the transfer case in
NEUTRAL. See ªParking Brakeº in the Index.
NEUTRAL: Shift the vehicle's transfer case to
NEUTRAL only when towing your vehicle. See
ªRecreational Vehicle Towingº or ªTowing Your
Vehicleº in the Index for more information.

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Parking Brake
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
flash. A chime will activate when the parking brake is
applied and the vehicle is moved at least 3 mph (5 km/h)
for at least three seconds.
To release the parking brake, hold the regular brake
pedal down. Pull the bottom edge of the lever, located
above the parking brake pedal, marked BRAKE
RELEASE, to release the parking brake.
If the ignition is on when the parking brake is released,
the brake system warning light will go off.
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.
If you are towing a trailer and are parking on any hill,
see ªTowing a Trailerº in the Index. That section shows
what to do first to keep the trailer from moving.

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If you have to leave your vehicle with the engine
running, be sure your vehicle is in PARK (P) and the
parking brake is firmly set before you leave it. After you
move 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) without first pulling it
toward you. If you can, it means that the shift lever
wasn't fully locked into PARK (P).
Torque Lock (Automatic Transmission)
If you are parking on a hill and you don't shift your
transmission into PARK (P) properly, the weight of the
vehicle may put too much force on the parking pawl in the
transmission. You may find it difficult to pull the shift
lever out of PARK (P). This is called ªtorque lock.º To
prevent torque lock, set the parking brake and then shift
into PARK (P) properly before you leave the driver's seat.
To find out how, see ªShifting Into PARK (P)º in
the Index.
When you are ready to drive, move the shift lever out
of PARK (P) before you release the parking brake.
If torque lock does occur, you may need to have another
vehicle push yours a little uphill to take some of the
pressure from the parking pawl in the transmission,
so you can pull the shift lever out of PARK (P).
Shifting Out of PARK (P)
(Automatic Transmission Only)
If your vehicle has an automatic transmission shift lock
control system, you have to fully apply your regular
brakes before you can shift from PARK (P) when the
ignition is in RUN. See ªAutomatic Transmissionº in
the Index.
If you cannot shift out of PARK (P), ease pressure on
the shift lever and push the shift lever all the way up
into PARK (P) as you maintain brake application.
Then, move the shift lever into the gear you want.
If you ever hold the brake pedal down but still can't
shift out of PARK (P), try this:
1. Turn the key to the OFF ignition position.
2. Apply and hold the brake until the end of Step 4.
3. Shift the vehicle to NEUTRAL (N).
4. Start the vehicle and then shift to the drive gear
you want.
5. Have the system fixed as soon as you can.