1998 GMC SIERRA service

Synchronization
Synchronization may be necessary d~te 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 scme 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 forjoy riders
01- 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.
Ycx~r steering wheel will be locked, and so will your
ignition.
If you have an automatic transmission, taking
your key
out also locks your transmission. And
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
If you park in a lot where someone will be watching
your vehicle, it's 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.
Lock all the doors except the driver's.
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Passlock@ New Vehicle “Break-In”
Your vehicle is equipped with the Passlock
theft-deterrent system.
Passlock is a passive theft-deterrent system. The
system
is armed once the key is removed from the ignition.
Passlock enables fuel if the ignition lock cylinder
is
turned with a valid key. If a correct key is not used, f~lel
is disabled.
During normal operation, the
SECURITY light will go
off after the engine is started.
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 the
START position as soon as the engine starts.
If you are driving 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 fuse (see “Fuses
and Circuit Breakers” in the
Index), See your dealer for service.
If the SECURITY light comes on while the engine is
running, a problem has been detected and the system
may need service. See your dealer for service.
In an emergency, call the Roadside Assistance Center.
NOTICE:
Your vehicle doesn’t need an elaborate
“break-in.” But it will perform better in the long
run if you follow these guidelines:
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Keep your speed at 55 mph (88 kmh) or
less for the first
500 miles (805 km).
Don’t drive at any one speed
-- fast or
slaw
-- 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.
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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.
Key Release Button (Manual Tr :--:I: ssion)
The ignition key cannot be
relnoved from the ignition
of manual transmission
vehicles unless the key
release button is used.
To remove the key on n-mual transmission vehicles,
turn the key to OFF, then press the button and turn the
key
to LOCK. Do not hold the button in while turning
the key
to OFF. Keeping your finger on the button, pull
the key straight out.
On automatic transmission vehicles, turn the key to
LOCK and pull it straight out.
Starting Your Gasoline Engine
If you have ;I diesel engine, see “Starting Your Diesel
Engine”
in the Diesel Engine Supplement.
Automatic Transmission
Move your shift lever to PARK (P) or NEUTRAL (N).
Your engine won‘t start in any other position -- that’s a
safety feature. To restart when you‘re already moving,
use NEUTRAL
(N) only.
NOTICE:
Don’t try to shift to PARK (P) if your vehicle is
moving. If
you do, you could damage the
transmission. Shift to
PARK (P) only when your
vehicle
is stopped.
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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.
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
with some delay.
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
with some delay.
ting from 2HI or 4HI to 4LO
'li hift from 2HI or 4HI to 4L0, 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 kmh). 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.
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 kmh) and the
transmission is
in NEUTRAL (N). After 30 seconds the
transfer case will return to 4HI.
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Air Bag Readiness Light
There is an air bag readiness light on the instrument panel,
which shows AIR BAG. The system checks
the air bag’s
electrical system for malfunctions. The light tells
you if
there is an electrical problem. The system check includes
the air bag sensors, the air bag module, the wiring and the
diagnostic module. For more information
on the air bag
system, see “Air Bag”
in the Index,
~
AIR
BAG
This light will come on
when you start your engine,
and
it will flash for a few
seconds. Then the light
should go out. This means
the system is ready.
If the air bag readiness light stays on after you start the
engine or comes on when
you are driving, your air bag
system may not work properly. Have your vehicle
serviced right away.
The air bag readiness light should flash for a few
seconds 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.
AIR BAG OFF Light (Except Crew Cab)
When you turn the right front passenger’s air bag off, this
light will come
on and stay on to remind you that the air
bag has been turned off. This light will go off when you
turn the air bag back on again. See “Securing a Child
Restraint in the Right Front Seat Position”
in the Index for
more on this, including important safety information.
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If the right front passenger’s air bag is turned
off, an adult or
a child who is no longer an infant
sitting in the right front passenger’s position
won’t have the extra protection of an air bag. In
a crash, the air bag wouldn’t be able to inflate
and help protect the person sitting there. Make
sure the air bag is turned on unless you are using
a rear-facing child restraint in the right front
seat position.
A
A 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 secure a rear-facing child
restraint in your vehicle until you have your
vehicle serviced.
Charging System Indicator Light
7-1 This light should come on
I-+I
brieflywhen you turn on the
ignition, before starting the
engine,
as a check to show
you it is working.
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After the engine starts, the light should go out. If it stays
on or comes on while you are driving, you may have a
problem with your charging system. It could indicate a
problem with the generator
drive belt, or some other
charging system problem. Have it checked right away.
Driving while this light
is on could drain your battery.
If you must drive a short distance with this light on, it
helps to turn off all your accessories, such as the radio
and the
air conditioner.
Voltmeter
19
When your engine is not
running, but the ignition is
in RUN, this gage shows
your battery’s state of
charge in
DC volts.
When the engine is running, the gage shows the
condition of the charging system. Readings between the
low and high warning zones indicate the normal
operating range. 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.
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If the warning light comes on, there co11ld be a brake
problem. Have your brake system inspected right away.
This light should come on
(a) (@)
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. BRAKE
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 “Towing Your Vehicle”
in the Index.)
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
ANTI -
LOCK
your engine and may stay
on for several seconds.
That’s normal.
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