lock GMC SIERRA 1998 Service Manual

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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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
“Brake System Warning Light” 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.
Engine Coolant Temperature Gage
1
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 (1 25 “C) mark. If the
gage reaches the
260°F (125°C) mark, it indicates that
the cooling system is working beyond its capacity.
The “Problems on
the Road,” section of this manual shows
what
to do. See “Engine Overheating” in the Index.
Malfunction Indicator Lamp (Service
Engine
Soon Light) (Gasoline Engine)
SERVICE
ENGINE
SOON
Your vehicle is equipped
with a computer which
monitors operation
of the
fuel, ignition and emission
control systems.
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Security Light
SECURITY
This light will come on
briefly when you turn the
key to
START.
The light will stay on until the engme starts. If the light
flashes, the Passlock@ System has entered a tamper
mode. If the vehicle fails
to start, see “Passlock” in
the Index.
If the light comes on continuously while driving and
stays
on, there may be a problem with the Passlock
System. Your vehicle will
not be protected by Passlock,
and you should see your
GM dealer.
Up Shift Light (If Equipped)
This light is used on
some models with
manual transmissions.
The
SHIFT indicator light will help you get the best fuel
economy. See ‘(Shift Light” or ;’Shift Speeds”
in this
section for more information.
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Section 3 Comfort Controls and Audio Systems
In this section, you’ll find out how to operate the comfort control and audio systems offered with your vehicle. Be
sure to read about the particular systems supplied with your vehicle.
3-2 3
-4
3-5
3-5
3-6
3-6 3
-7
3-7
3-7
3-8
3-9
3-12 Comfort
Controls
Air Conditioning
Heating
Ventilation System
Defogging and Defrosting Rear Window Defogger
(If Equipped)
Audio Systems Setting the Clock
AM-FM Stereo Radio
Playing the Radio
AM-FM Stereo with Cassette
Tape Player
(If Equipped)
AM-FM Stereo with Cassette Tape and
Automatic
Tone Control (If Equipped) 3-
15
3- 16
3-20
3-2
1
3-23
3-24
3-25
3-26
3-26
3-26 CD
Adapter
Kit
AM-FM Stereo with Compact Disc Player and
Automatic Tone Control
(If Equipped)
Remote Compact Disc Player (If Equipped)
Theft-Deterrent Feature
Understanding Radio Reception
Tips About Your Audio System
Care of Your Cassette Tape Player
Care
of Your Compact Discs
Care of Your Compact Disc Player
Fixed Mast Antenna
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.
NOTICE:
Don’t use a razor blade or something else sharp
on the inside
of the rear window. If you do, you
could cut
or damage the warming grid, and the
repairs wouldn’t be covered
by your warranty.
Audio Systems
Your Delco Electronics audio system has been designed
to operate easily and give years of listening pleasure.
You will get the most enjoyment out of it if you acquaint
yourself with
it first. Find out what your Delco
Electronics system can do and how to operate
all its
controls,
to be sure you’re getting the most out of the
advanced engineering that went into it.
Setting the Clock for Systems without
Automatic Tone Control
Press SET. Within five seconds, press and hold the
SEEK right arrow
until the correct minute appears on
the display. Press and
hold the SEEK left arrow until the
correct hour appears
on the display.
Setting the Clock for Systems with
Automatic Tone
Control
Press and hold HR until the correct hour appears on the
display. Press and hold
MN until the correct minute
appears on the display.
To display the clock with the
ignition
off, press RECALL or HR/MN and the time
will be displayed for a few seconds. There is an initial
two-second delay before the clock goes into the
time-set mode.
AM-FM Stereo
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REV (4): Press and hold this button to quickly reverse
within a track. As the CD reverses, elapsed time will be
displayed
to help you find the correct passage.
FWD (6): Press and hold this button to quickly advance
within
a track. As the CD advances, elapsed time will be
displayed to help you find the correct passage.
SEEK: Press the left arrow while playing a CD to go
back
to the start of the current track. It will go back to
the current track
if more than eight seconds have played.
Press the left arrow again
to go to previous tracks. Press
the right arrow
to go to the next higher track on the disc.
RANDOM: Press P.SCAN to enter the random play
mode. RANDOM will appear on the display. While in
this mode, the tracks on the discs will be played in
random order. If you press SEEK,
PREV or NEXT
while
in the random mode, the previous or next track
will be scanned randomly. Press P.SCAN again to turn
off RANDOM and return
to normal operation.
RECALL: Press this button to see what track is
currently playing. Press RECALL again within five
seconds to see how long the track has been playing.
When a new track starts
to play, the track number will
also appear. Press RECALL
a third time and the time of
day will be displayed.
TAPE AUX: With a disc loaded in the player and the
radio playing, press this button once to play the compact
disc. To return to playing
the radio, press AM-FM. If
both a cassette tape and CD are loaded, press TAPE
AUX to switch between the tape and compact disc.
EJECT Press this button on the remote player to eject a
compact disc.
Theft-Deterrent Feature (If Equipped)
THEFTLOCK@ is designed to discourage theft of your
radio.
It works by using a secret code to disable all radio
functions whenever battery power is removed.
The THEFTLOCK feature for the radio may be used or
ignored. If ignored,
the system plays normally and the
radio is not protected by the feature.
If THEFTLOCK is
activated, your radio will not operate
if stolen.
When THEFTLOCK is activated, the radio will display
LOC to indicate
a locked condition anytime battery
power has been interrupted.
If your battery loses power
for any reason,
you must unlock the radio with the secret
code before
it will operate.
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Activating the Theft-Deterrent Feature
The instructions which follow explain how to enter your
secret code to activate the THEFTLOCK system.
It is
recommended that you read through all nine steps
before starting the procedure.
NOTE:
If you allow more than 15 seconds to elapse
between any steps, the radio autonlatically reverts to
time and
you must start the procedure over at Step 4.
1. Write down any three or four-digit number from
000 to 1999 and keep it in a safe place separate from
the vehicle.
2. Turn the ignition to ACCESSORY or RUN.
3. Turn the radio off.
4. Press the 1 and 4 buttons together. Hold them down
until --- shows on the display. Next you will use the
secret code number which you have written down.
5. Press MN and 000 will appear on the display.
6. Press MN again to make the last two digits agree
with your code.
7. Press HR to make the first one or two digits agree
with your code.
8.
9.
Press AM-FM after you have confirmed that the
code matches the secret code you have written down.
The display
will show REP to let you know that you
need to repeat Steps
5 through 7 to confirm your
secret code.
Press AM-FM and
this time the display will show
SEC to let you know that your radio
is secure. The
indicator
by the volume control will begin flashing
when the ignition is turned off.
Unlocking the Theft-Deterrent Feature After a
Power Loss
Enter your secret code as follows; pause no more than
15 seconds between steps:
1. LOC appears when the ignition is on.
2. Press MN and 000 will appear on the display.
3. Press MN again to make the last two digits agree
with your code.
4. Press HR to make the first one or two digits agree
with your code.
5. Press AM-FM after you have confirmed that the
code matches the secret code you have written down.
The display
will show SEC, indicating the radio is
now operable and secure.
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If you enter the wrong code eight times, INOP will
appear on
the display. You will have to wait an hour
with the ignition on before you can try again. When you
try again,
you will only have three chances to enter the
correct code before INOP appears.
If you lose or forget your code, contact your dealer.
Disabling the Theft-Deterrent Feature
Enter your secret code as follows; pause no more than
15 seconds between steps:
1. Turn the ignition to ACCESSORY or RUN.
2. Turn the radio off.
3. Press the 1 and 4 buttons together. Hold them down
until SEC shows on the display.
4. Press MN and 000 will appear on the display.
5. Press MN again to make the last two digits agree
with your code.
6. Press HR to make the first one or two digits agree
with your code.
1. Press AM-FM after you have confirmed that the
code matches the secret code you have written down.
The display will show
---, indicating that the radio
is no longer secured.
If the code entered is incorrect, SEC will appear on the
display. The radio
will remain secured until the correct
.code is entered.
When battery power is removed and later applied to a
secured radio, the radio won‘t turn on and
LOC will
appear
on the display.
To unlock a secured radio, see “Unlocking the
Theft-Deterrent Feature After a Power
Loss” earlier
in this section.
Understanding Radio Reception
AM
The range for most AM stations is greater than for FM,
especially at night. The longer range, however, can
cause stations to interfere with each other. AM can pick
up noise from things like storms and power lines. Try
reducing the treble to reduce this noise
if you ever get it.
FM Stereo
FM stereo will give you the best sound, but FM signals
will reach only about 10 to 40 miles (16 to 65 km). Tall
buildings or hills can interfere
with FM signals, causing
the sound to come and
go.
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If your engine ever stops while you’re driving, brake
normally but don’t pump your brakes.
If you do, the
pedal may get harder to push down. If your engine
stops, you will still have some power brake assist. But
you will use it when you brake. Once the power assist is
used up, it may take longer to stop and the brake pedal
will be harder to push.
Anti-Lock Brakes (ABS)
Your vehicle has anti-lock brakes (ABS). ABS is an
advanced electronic braking system that will help
prevent a braking skid.
When you start your engine and begin
to drive away,
your anti-lock brake system will check itself. You may
hear
a momentary motor or clicking noise while this
test is going on. This is normal.
(@!
ANTI -
If there’s a problem with
the anti-lock brake system,
this warning light will stay
on. See “Anti-Lock Brake
System Warning Light”
in
I LOCK I the Index. Here’s how
anti-lock works. Let’s say the road
is wet.
You’re driving safely. Suddenly an animal jumps out
in
front of you.
You slam
on the brakes. Here’s what happens with ABS.
A computer senses that wheels are slowing down. If one
of the wheels is about to stop rolling, the computer will
separately work the brakes at each front wheel and at
both rear wheels.
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The anti-lock system can change the brlzke pressure faster
than any driver could. The computer is programmed
to
make the most of available tire and road conditions.
You can steer around the obstacle while braking hard.
As you brake, your computer keeps receiving updates on
wheel speed and controls braking pressure accordingly. Remember: Anti-lock doesn’t change the
time you need
to get your foot
up to the brake pedal or always decrease
stopping distance.
If you get too close to the vehicle in
front of you, you won’t have time to apply your brakes
if that vehicle. suddenly slows or stops. Always leave
enough room
up ahead to stop, even though you have
anti-lock brakes.
Using Anti-Lock
Don’t pump the brakes. Just hold the brake pedal down
firmly and let anti-lock work for you.
You may feel the
brakes vibrate, or you may notice some noise, but this is
normal. On vehicles
with four-wheel drive, your
anti-lock brakes work at all times
-- whether you are in
two-wheel drive or four-wheel drive.
Braking in Emergencies
With anti-lock, you can steer and brake at the same
time. In many emergencies, steering can help you more
than even the very best braking.
Steering
Power Steering
If you lose power steering assist because the engine
stops
or the system is not functioning, you can steer but
it will take much more effort.
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