1998 GMC SIERRA ignition

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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Care of Your Cassette Tape Player
A tape player that is not cleaned regularly can cause
reduced sound quality, ruined cassettes or a damaged
mechanism. Cassette tapes should be stored
in their
cases away from contaminants, direct sunlight and
extreme heat.
If they aren't, they may not operate
properly or may cause failure of the tape player.
Your tape player should be cleaned regularly after every
50 hours of use. Your radio may display CLN to indicate
that you have used your tape player for
50 hours without
resetting the tape clean timer.
If this message appears on
the display, your cassette tape player needs to be
cleaned. It will still play tapes, but you should clean
it as
soon as possible to prevent damage to your tapes and
player.
If you notice a reduction in sound quality, try a
known good cassette to see
if it is the tape or the tape
player at fault.
If this other cassette has no improvement
in sound quality, clean the tape player.
The recommended cleaning method for your cassette
tape player is the use
of a scrubbing action,
non-abrasive cleaning cassette with pads which scrub
the tape head
as the hubs of the cleaner cassette turn.
The recommended cleaning cassette is available through
your dealership
(GM Part No. 12344789).
When using a scrubbing action, non-abrasive cleaning
cassette,
it is normal for the cassette to eject while
cleaning because your
unit is equipped with a cut tape
detection feature and some cleaning cassettes may
appear as
a broken tape. To prevent the cleaning cassette
from being e-jected, use
the following steps:
If your vehicle is equipped with the AM-FM Stereo with
Cassette Tape Player:
1.
2.
3.
4.
5.
Turn the ignition to RUN or ACCESSORY.
Turn the radio on.
Insert the scrubbing action cleaning cassette.
Within five seconds, press and hold the
REV and
FWD buttons at the same time for three seconds. The
tape symbol on the display will flash, showing that
the cut tape detections feature is no longer active.
Eject the cleaning cassette after the manufacturer's
recommended cleaning time.
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If your vehicle is equipped with the AM-FM Stereo with
Cassette Tape Player and Automatic Tone Control:
1. Turn the ignition to RUN or ACCESSORY.
2. Turn the radio off.
3. Press and hold the TAPE AUX button for
five seconds. The tape symbol
on the display will
flash for two seconds.
4. Insert the scrubbing action cleaning cassette.
5. Eject the cleaning cassette after the manufacturer's
recommended cleaning time.
When the cleaning cassette has been ejected, the cut tape
detection feature is active again.
You may also choose
a non-scrubbing action, wet-type
cleaner which uses
a cassette with a fabric belt to clean
the tape head. This type of cleaning cassette will not
eject
on its own. A non-scrubbing action cleaner may
not clean as thoroughly as the scrubbing type cleaner.
The use of
a non-scrubbing action, dry-type cleaning
cassette is not recommended
After you clean the player, press and hold EJECT for
five seconds to reset the CLN indicator. The radio
will
display --- to show the indicator was reset.
Cassettes are subject to wear and the sound quality
may
degrade over time. Always Incake sure the cassette tape is in
good condition before you have yo~~r tape player serviced.
Care of Your Compact Discs
Handle discs carefully. Store them in their original cases
or other protective cases and away from direct sunlight
and dust.
If the surface of a disc is soiled, dampen a
clean, soft cloth in a mild, neutral detergent solution and
clean
it, wiping from the center to the edge.
Be sure never to touch the signal surface when handling
discs. Pick up discs by grasping the outer edges or the
edge of the hole and the outer edge.
Care of Your Compact Disc Player
The use of CD lens cleaner discs is not advised, due to
the risk of contaminating the lens of the CD optics with
lubricants internal to the CD mechanism.
Fixed Mast Antenna
The fixed mast antenna can withstand most car washes
without being damaged.
If the mast should ever become
slightly bent, you can straighten
it out by hand. If the
mast is badly bent, as it might be by vandals, you should
replace it.
Check every once
in a while to be sure the mast is still
tightened
to the cowl.
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Driving in Water
Light rain causes no special off-road driving problems.
But heavy rain can mean flash flooding, and flood
waters demand extreme caution.
Find out how deep the water is before
you drive through
it. If it’s deep enough to cover your wheel hubs, axles or
exhaust pipe, don’t try it
-- you probably won’t get
through. Also, water that deep can damage your axle
and other vehicle parts.
If the water isn’t too deep, then drive through it slowly. \
At
fast speeds, water splashes on your ignition system and
your vehicle can stall. Stalling can also occur
if you get
your tailpipe under water. And, as long as your tailpipe is
under water, you’ll never
be able to start your engine.
When you
go through water, remember that when your
brakes get wet,
it may take you longer to stop.
.
Driving through rushing water can be dangerous.
Deep water can sweep your vehicle downstream
and you and your passengers could drown. If it’s
only shallow water, it can still wash away the
ground from under your tires, and you could lose
traction and roll the vehicle over. Don’t drive
through rushing water.
See “Driving Through Water’’ in the Index for more
information on driving through water.
After Off-Road Driving
Remove any brush or debris that has collected on the
underbody, chassis or under the hood. These
accumulations can be a fire hazard.
After operation in mud or sand, have the brake linings
cleaned and checked. These substances can cause
glazing and uneven braking. Check the body structure,
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Keep your vehicle in good shape. Check all fluid
levels and also the brakes, tires, cooling system and
transmission. These parts can work hard on
mountain roads.
Know how to go down hills. The most important
thing to know
is this: let your engine do some of the
slowing down. Shift to
a lower gear when you go
down a steep or long hill.
I A CAJTION: I
If you don’t shift down, your brakes could get so
hot that they wouldn’t work well. You would then
have poor braking or even none going down
a hill.
You could crash. Shift down to let your engine
assist your brakes on a steep downhill slope. Coasung
aownhill in NEUTRAL
(N) or with the
ignition
off is dangerous. Your brakes will have
to do all the work
of slowing down. They could
get
so hot that they wouldn’t work well. You
would then have poor braking or even none going
down
a hill. You could crash. Always have your
engine running and your vehicle in gear when
you go downhill.
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Know how ro g6 uphill. You may want to shift down
to a lower gear.
The lower gears help cool your engine
and transmission, and you can climb the hill better.
Stay in your own lane when driving on two-lane
roads in hills or mountains. Don’t swing wide or cut
across the center
of the road. Drive at speeds that let
you stay in your own lane.
0
0 As you go over the top of a hill, be alert. There could be
something in your lane, like a stalled car
or an accident.
You may see highway signs
on mountains that warn of
special problems. Examples are long grades, passing or
no-passing zones, a falling rocks area or winding
roads. Be alert
to these and take appropriate action.
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Four-Wheel-Drive Vehicles
(Manual Transfer Case Only)
‘A
-
Shifting the transfer case into NEUTRAL (N) can
cause your vehicle to roll even if the transmission
is in
PARK (P), for an automatic transmission, or
if your vehicle is in gear, for
a manual
transmission.
You or others could be injured.
Make sure the parking brake is firmly set before
you shift the transfer case into NEUTRAL (N).
Use the following procedure to correctly tow your
vehicle on all four wheels:
1.
2.
3.
4.
5.
6.
Firmly set the parking brake.
Place the transmission in
PARK (P) or a manual
transmission in FIRST
(1).
Securely attach the vehicle being towed to the
tow vehicle.
With the engine running, shift the transfer case to
NEUTRAL
(N). See “Four-wheel Drive” in the
Index for the proper procedure to select the neutral
position for your vehicle.
Release the parking brake only after the vehicle
being towed is firmly attached to the towing vehicle.
Turn the ignition to
OFF, The OFF position unlocks the
steering column and reduces battery
drain. Unlocking
the steering column will allow the proper movement
of
the front wheels and tires during towing.
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Using a Transfer Case Mounted Power
Take-Off (Automatic Transmission)
1.
2.
3.
4.
5.
6.
7.
Set the parking brake.
Turn the ignition off.
Shift the transfer case into NEUTRAL
(N).
Shift the transmission into NEUTRAL (N).
Engage the PTO.
If you are going to drive the vehicle. shift the
transfer case into the range you want. Turn
the
ignition to START. Then apply the regular brakes
and release the. parking brake.
Shift the transmission to THIRD
(3) to start the PTO.
Release the regular brakes to drive the vehicle.
Disengaging a Power Take-OFF
1. Turn the ignition off.
2. Put the transmission in PARK (P).
3. Release the PTO
4. Restart the engine.
Step-Bumper Pad
If your vehicle has a rear step bumper, it may be
equipped with
a rear step pad at the center of
the bumper.
If you will be using the
bumper to tow a trailer,
you
must remove the center
cutout circle to install the
trailer ball.
You must also
remove both outer cutouts
to attach the trailer safety chains.
To remove the pad,
lift the
edge of the pad from the
rear of the bumper and
swing it forward. When the
pad releases from the
bumper holes,
lift the
pad off.
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2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles aren’t touching
each other. If they are, it could cause a ground
connection
you don’t want. You wouldn’t be able
to start your vehicle, and the bad grounding could
damage the electrical systems.
To avoid the possibility
of the vehicles rolling, set
the parking brake firmly on both vehicles involved
in the jump start procedure. Put an automatic
transmission in
PARK (P) or a manual transmission
in NEUTRAL (N).
If you have a four-wheel-drive
vehicle, be sure the transfer case is not in
NEUTRAL
(N).
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or accessory power outlets. Turn
off all lamps
that aren’t needed as well as radios. This will avoid
sparks and help save both batteries. In addition, it
could save your radio!
I NOTICE:
If you leave your radio on, it could be badly
damaged. The repairs wouldn’t be covered by
your warranty.
4. Open the hoods and locate the batteries. Find the
positive
(+) and negative (-) terminals on each battery.
If your vehicle has air conditioning, the auxiliary
electric fan under the hood can start up even
when the engine is not running and can injure
you. Keep hands, clothing and tools
away from
any underhood electric fan.
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