1998 GMC ENVOY display

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
7. Press HR to make the first one or two digits agree
with your code.
with your
code.
8. 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.
9. 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
5. Press AM-FM after you have confirmed that the
with your code.
code matches the secret code
you have written down.
The display will show SEC, indicating the radio is
now operable and secure.
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.
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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.
7. 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 (1 6 to 65 km). Tall
buildings or hills can interfere with
FM signals, causing
the sound to come and go.
Tips About Your Audio System
Hearing damage from loud noise is almost undetectable
until it is too late. Your hearing can adapt to higher
volumes
of sound. Sound that seems normal can be loud
and harmful to your hearing. Take precautions by
adjusting the volume control on your radio to a safe
sound level before your hearing adapts to
it.
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To help avoid hearing loss or damage:
0 Adjust the volume control to the lowest setting.
Increase volume slowly until you hear comfortably
and clearly,
NOTICE:
Before you add any sound equipment to your
vehicle
-- like a tape player, CB radio, mobile
telephone or two-way radio
-- be sure you can
add what
you want. If you can, it’s very
important to do it properly. Added sound
equipment may interfere with the operation
of
your vehicle’s engine, Delco Electronics radio or
other systems, and even damage them. Your
vehicle’s systems may interfere with the
operation
of sound equipment that has been
added improperly.
So, before adding sound equipment, check with
your dealer and be sure
to check Federal rules
covering mobile radio and telephone units.
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
SO 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).
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When using a scrubbing action, non-abrasive cleaning
cassette,
it is normal for the cassette to eject because
your unit is equipped with a cut tape detection feature
and
a cleaning cassette may appear as a broken tape. To
prevent the cleaning cassette from being ejected, use the
following steps.
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 make sure the cassette
tape is
in good condition before you have your tape
player serviced.
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