2001 GMC SONOMA service

1-52
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 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.
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 pickup or an extended
cab pickup 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. On all
models, 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.
3. Pick up the latch plate, and run the lap and shoulder
portions of the vehicle's safety belt through or
around the restraint. The child restraint instructions
will show you how.
If the shoulder belt goes in front of the child's face or
neck, put it behind the child restraint.

2-11
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 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
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: When you press UNLOCK, the driver's
door will unlock automatically, the parking lamps will
flash and the interior lights will go on. If you press
UNLOCK again within three seconds, the remaining
doors will unlock, the parking lamps will flash 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.
Remote Panic Alarm
When the horn symbol button on the key 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 symbol button again,
waiting for 30 seconds, or starting the vehicle.

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To replace the battery in the keyless entry transmitter:
1. Insert a thin coin in the slot between the covers of
the transmitter housing near the key ring hole.
Remove the bottom by twisting the coin.
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 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 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.

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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
110 seconds, 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 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.
The alarm won't stop if you try to unlock a door any
other way.
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 light 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.

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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 about 10 minutes 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 does not start after three tries, the vehicle
needs service.
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.
New Vehicle ªBreak-Inº
NOTICE:
Your vehicle doesn't need an elaborate
ªbreak
-in.º 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 ªTowing a Trailerº in the Index for
more information.

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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. But 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
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).
RUN (D): This is the position for driving.
START (E): 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 used.
To remove the key on manual transmission vehicles,
turn the key to OFF. Then turn the key to LOCK while
pressing the key release button down at the same time.
Pull the key straight out.
On automatic transmission vehicles, turn the key to
LOCK and pull it straight out.

2-30 Electronic Transfer Case
The electronic transfer case
switches are located to the
right of the steering wheel.
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. When this lamp is lit, it is about
one
-half as bright as the others.
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 one 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.
Shifting from 2HI to 4HI
Press and release the 4HI switch. This can be done at
any speed, and the front axle will lock automatically.
Shifting from 4HI to 2HI
Press and release the 2HI switch. This can be done at
any speed, and the front axle will unlock automatically.

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Shifting from 2HI or 4HI to 4LO
To shift from 2HI or 4HI to 4LO, the vehicle must be
stopped or moving less than 3 mph (4.8 km/h) with
the transmission in NEUTRAL (N) in vehicles equipped
with an automatic transmission or the clutch pedal
engaged in vehicles equipped with a manual transmission.
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 into gear or
releasing the clutch pedal.
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 slower than 3 mph (4.8 km/h) and the transmission
is in NEUTRAL (N) or the clutch pedal engaged.
On automatic transmission equipped vehicles, if your
transfer case does not shift into 4LO, your transmission
indicator switch may require adjustment. With your
transmission in NEUTRAL (N), press and release the
4LO switch. While the 4LO indicator light is flashing,
shift your transmission into PARK (P). Wait until the
4LO indicator light remains illuminated before shifting
your transmission into gear. This will get you into 4LO,
but you should take your vehicle in for service to restore
normal operation.Shifting from 4LO to 4HI or 2HI
To shift from 4LO to 4HI or 2HI, your vehicle must be
stopped or moving less than 3 mph (4.8 km/h) with the
transmission in NEUTRAL (N) or the clutch pedal
engaged. 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 switch. You must
wait for the 4HI indicator light to stop flashing and
remain illuminated before shifting your transmission
into gear or releasing the clutch pedal.
If the 4HI switch is pressed when your vehicle is in gear
and/or moving, the 4HI indicator light will flash for
30 seconds but not complete the shift unless the vehicle
is moving slower than 3 mph (4.8 km/h) and the
transmission is in NEUTRAL (N) or the clutch
pedal engaged.
On automatic transmission equipped vehicles, if your
transfer case does not shift into 4HI, your transmission
indicator switch may require adjustment. With your
transmission in NEUTRAL (N), press and release the
4HI switch. While the 4HI indicator light is flashing,
shift your transmission into PARK (P). Wait until the
4HI indicator light remains illuminated before shifting
your transmission into gear. This will get you into 4HI,
but you should take your vehicle in for service to restore
normal operation.