2001 GMC SIERRA service

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CAUTION: (Continued)
If this ever happens, don't let anyone whom the
national government has identified as a member
of a passenger air bag risk group sit in the right
front passenger's position (for example, don't
secure a rear
-facing child restraint in your
vehicle) until you have your vehicle serviced.
See ªAir Bag Off Switchº in the Index.
Crew Cab Models: Your vehicle has a right front
passenger air bag. Never put a rear
-facing child
restraint in this seat. Here's why:
CAUTION:
A child in a rear-facing child restraint can be
seriously injured or killed if the right front
passenger's air bag inflates. This is because the
back of the rear
-facing child restraint would be
very close to the inflating air bag. Always secure
a rear
-facing child restraint in the rear seat.
Although a rear seat is a safer place, you can secure a
forward
-facing child restraint in the right front seat.Regular Cab and Extended Cab Models: Your vehicle
has a right front passenger air bag. There's a switch on
the instrument panel that you can use to turn off the
right front passenger's air bag when you want to secure
a rear
-facing child restraint at the right front passenger's
position. See ªAir Bag Off Switchº in the Index for
more on this, including important safety information.
CAUTION:
A child in a rear-facing child restraint can be
seriously injured or killed if the right front
passenger's air bag inflates. This is because the
back of the rear
-facing child restraint would be
very close to the inflating air bag. Be sure to
turn off the air bag before using a rear
-facing
child restraint in the right front seat position.
If a forward
-facing child restraint is suitable for
your child, always move the passenger seat as far
back as it will go.

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Although a rear seat is a safer place, you can secure a
forward
-facing child restraint in the right front seat.
CAUTION:
If the air bag readiness light ever comes on when
you have turned off the air bag, it means that
something may be wrong with the air bag system.
The right front passenger's air bag could inflate
even though the switch is off.
If your vehicle is a regular cab pickup and
this ever happens, don't let anyone whom the
national government has identified as a member
of a passenger air bag risk group sit in the right
front passenger's position (for example, don't
secure a rear
-facing child restraint in your
vehicle) until you have your vehicle serviced.
See ªAir Bag Off Switchº in the Index.
CAUTION: (Continued)
CAUTION: (Continued)
If your vehicle is an extended cab pickup and
this ever happens, don't let anyone whom the
national government has identified as a member
of a passenger air bag risk group sit in the right
front passenger's position (for example, don't
secure a rear
-facing child restraint in the right
front passenger's seat) until you have your vehicle
serviced. See ªAir Bag Off Switchº in the Index.
You'll be using the lap-shoulder belt. See the earlier
part about the top strap if the child restraint has one.
Be sure to follow the instructions that came with the
child restraint. Secure the child in the child restraint
when and as the instructions say.
1. Your vehicle has a right front passenger's air bag.
If your vehicle is a regular cab or an extended cab
and you are using a rear
-facing child restraint in this
seat, make sure the air bag is turned off. See ªAir
Bag Off Switchº in the Index. If your child restraint
is forward
-facing, always move the seat as far
back as it will go before securing it in this seat.
See ªSeatsº in the Index.
2. Put the restraint on the seat.

2-10
Keyless Entry System (If Equipped)
If your vehicle has this feature, you can lock and unlock
your doors from about 3 feet (1 m) up to 100 feet (30 m)
away using the remote keyless entry transmitter supplied
with your vehicle.
Your keyless entry system operates on a radio frequency
subject to Federal Communications Commission (FCC)
Rules and with Industry Canada.
This device complies with Part 15 of the FCC Rules.
Operation is subject to the following two conditions:
(1) this device may not cause harmful interference, and
(2) this device must accept any interference received,
including interference that may cause undesired operation.
This device complies with RSS
-210 of Industry Canada.
Operation is subject to the following two conditions: (1) this
device may not cause interference, and (2) this device must
accept any interference received, including interference that
may cause undesired operation of the device.
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 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
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: Pressing this button once will unlock
the driver's door. The parking lamps will flash and the
interior lights will come on. Pressing UNLOCK again
within three seconds will cause the remaining doors to
unlock. The parking lamps will flash and the interior
lights will come on.

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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.

2-17
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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LOCK (B): This position locks your ignition and
transmission. It's a theft
-deterrent feature. You will only
be able to remove your key when the ignition is turned
to LOCK.
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? 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.
OFF (C): This position lets you turn off the engine.
Use OFF if you must have your vehicle in motion while
the engine is off (for example, if your vehicle is
being pushed).
RUN (D): This is the position for driving.
START (E): This position starts your engine.

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Indicator lights in the switches show which setting your
transfer case is in. The indicator lights will come on
briefly when you turn on the ignition and one will stay
on. If the lights do not come on, you should take your
vehicle to your dealer for service. An indicator light will
flash while the transfer case is being shifted. It will
remain illuminated when the shift is complete. If for
some reason the transfer case cannot make a requested
shift, it will return to the last chosen setting.
If the SERVICE 4WD light stays on, you should take
your vehicle to your dealer for service. See ªService
4WDº in the Index for further information.
Shifting to 4HI or AUTO 4WD
Press and release the 4HI or AUTO 4WD switch. This can
be done at any speed (except when shifting from 4LO),
and the indicator light will flash while shifting. It will
remain illuminated when the shift is completed.
Shifting to 2HI
Press and release the 2HI switch. This can be done at
any speed (except when shifting from 4LO).Shifting to 4LO
To shift to 4LO, the ignition must be in RUN and the vehicle
must be stopped or moving less than 3 mph (4.8 km/h) with
the transmission in NEUTRAL (N). The preferred method
for shifting into 4LO is to have your vehicle moving 1 to
2 mph (1.6 to 3.2 km/h). Press and release the 4LO switch.
You must wait for the 4LO indicator light to stop flashing and
remain illuminated before shifting your transmission in gear.
If the 4LO switch is pressed when your vehicle is in
gear and/or moving, the 4LO indicator light will flash
for 30 seconds and not complete the shift unless your
vehicle is moving less than 3 mph (4.8 km/h) and the
transmission is in NEUTRAL (N). After 30 seconds the
transfer case will return to the setting last chosen.
Shifting Out of 4LO
To shift from 4LO to 4HI, AUTO 4WD or 2HI your vehicle
must be stopped or moving less than 3 mph (4.8 km/h) with
the transmission in NEUTRAL (N) and the ignition in RUN.
The preferred method for shifting out of 4LO is to have your
vehicle moving 1 to 2 mph (1.6 to 3.2 km/h). Press and
release the 4HI, AUTO 4WD or 2HI switch. You must wait
for the 4HI, AUTO 4WD or 2HI indicator light to stop
flashing and remain illuminated before shifting your
transmission into gear.

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Electronic Transfer Case (If Equipped)
If your four-wheel-drive vehicle has the electronic
transfer case, the transfer case switches are located to
the left of the instrument panel cluster.
Use these switches to shift into and out of four
-wheel
drive. You can choose among three driving settings:
2HI: This setting is for driving in most street and
highway situations. Your front axle is not engaged in
two
-wheel drive.
4HI: This setting engages your front axle to help drive
your vehicle. Use 4HI when you need extra traction, such
as on snowy or icy roads, or in most off
-road situations.
4LO: This setting also engages your front axle to give
you extra traction. You may never need 4LO. It sends
the maximum power to all four wheels. You might
choose 4LO if you were driving off
-road in sand, mud
or deep snow and climbing or descending steep hills.
Indicator lights in the switches show you which setting
you are in. The indicator lights will come on briefly
when you turn on the ignition and the last chosen setting
will stay on. If the lights do not come on, you should
take your vehicle in for service. An indicator light will
flash while shifting. It will remain illuminated when the
shift is completed. If for some reason the transfer
cannot make a requested shift, it will return to the last
chosen setting.