AUX GMC SUBURBAN 1999 Owner's Manual

vi
GENERAL MOTORS, GM, the GM Emblem, GMC,
the GMC Emblem and the name YUKON are registered
trademarks of General Motors Corporation.
This manual includes the latest information at the time
it was printed. We reserve the right to make changes
in the product after that time without further notice.
For vehicles first sold in Canada, substitute the name
ªGeneral Motors of Canada Limitedº for GMC
whenever it appears in this manual.
Please keep this manual in your vehicle, so it will be
there if you ever need it when you're on the road. If you
sell the vehicle, please leave this manual in it so the new
owner can use it.
We support voluntary
technician certification.
For Canadian Owners Who Prefer a
French Language Manual:
Aux propri‡taires canadiens: Vous pouvez vous
procurer un exemplaire de ce guide en fran†ais chez
votre concessionaire ou au:
DGN Marketing Services Ltd.
1577 Meyerside Dr.
Mississauga, Ontario L5T 1B9

2-46
The fog lamps will go off whenever your high-beam
headlamps come on. When the high beams go off, the
fog lamps will come on again.
The fog lamps will be cancelled after the ignition is
turned off. If you still want to use the fog lamps after
you restart the vehicle, you will need to press the fog
lamp switch again.
Auxiliary Roof Mounted Lamp Switch
(If Equipped)
This switch includes wiring
provisions for a dealer or a
qualified service center to
install an auxiliary roof
lamp. This switch is located
on the center of the
instrument panel near
the comfort controls.
When the switch wiring is connected to an auxiliary roof
mounted lamp, pressing the button will activate the lamp
and illuminate an indicator light near the button. Pressing
the button again will turn off the roof mounted lamp.If your vehicle has this switch, your vehicle may have
the Snow Plow Prep Package. For further information
see ªSnow Plow Prep Packageº in the Index.
Interior Lamps
Instrument Panel Intensity Control
The instrument panel intensity control is located to the
right of the headlamp switch.
Rotate the thumbwheel up to increase the intensity of
the instrument panel lights. To turn on the dome lamps,
with the vehicle doors closed, rotate the thumbwheel all
the way up. Rotate the thumbwheel down to decrease
the intensity of the lights.
Exit Lighting
With exit lighting, the interior lamps will come on when
you remove the key from the ignition. The lights will
not come on if the DOME OVERRIDE button is
pressed in.
Illuminated Entry
Your vehicle is equipped with an illuminated entry feature.
When the doors are opened, the dome lamps will come
on if the DOME OVERRIDE button is in the ªoutº
position. If the DOME OVERRIDE button is pressed in,
the lamps will not come on.

2-75
See ªMessage Centerº in the Index for further information.
If the transmission fluid reaches temperatures of
approximately 275
F (135
C) or greater, the message
center will display a TRANS HOT...IDLE ENG warning
message. Pull the vehicle off the roadway when it is safe
to do so. Set the parking brake, place the transmission in
PARK (P) and allow the engine to idle until the
transmission temperature falls below 260
F (127
C).
If the transmission continues to operate above 265
F
(130
C), please contact your nearest dealer or the
GM Roadside Assistance Center.
NOTICE:
If you keep driving your vehicle with the
transmission temperature gage above the
normal operating range, you can damage the
transmission. This could lead to costly repairs
that may not be covered under your warranty.
The following situations can cause the transmission to
operate at higher temperatures:

Towing a trailer

Hot outside air temperatures

Hauling a large or heavy load

Low transmission fluid level

High transmission fluid level

Restricted air flow to the radiator and the auxiliary
transmission oil cooler (if equipped).
A temporary solution to hotter transmission operating
temperatures may be to let the transmission cool down.
If the transmission is operated at higher temperatures on
a frequent basis, see ªScheduled Maintenanceº in the
Index for the proper transmission maintenance intervals.

2-84
The following situations can cause the transmission to
operate at higher temperatures:

Towing a trailer

Hot outside air temperatures

Hauling a large or heavy load

Low transmission fluid level

High transmission fluid level

Restricted air flow to the radiator and the auxiliary
transmission oil cooler (if equipped).
A temporary solution to hotter transmission operating
temperatures may be to let the transmission cool down.
If the transmission is operated at higher temperatures on
a frequent basis, see ªScheduled Maintenanceº in the
Index for the proper transmission maintenance intervals.TRANS HOT...IDLE ENGINE
Your vehicle has a transmission over-temperature
display contained in the message center.
If this warning message is
displayed, pull the vehicle
off the roadway when it is
safe to do so.
Set the parking brake and place the transmission in
PARK (P). Idle the engine until the message center no
longer displays a message. If idling the engine does not
turn the warning message off after 10 to 15 minutes,
contact your nearest dealer or the GM Roadside Assistance
Center. See ªRoadside Assistanceº in the Index.
NOTICE:
If you keep driving your vehicle with the
transmission TRANS HOT...IDLE ENGINE
message displayed, you can damage the
transmission. This could lead to costly repairs
that may not be covered under your warranty.

2-85
The following situations can cause the transmission to
operate at higher temperatures:

Towing a trailer

Hot outside air temperatures

Hauling a heavy load

Low transmission fluid level

High transmission fluid level

Restricted air flow to the radiator and the auxiliary
transmission oil cooler (if equipped).
A temporary solution to hotter transmission operating
temperatures may be to let the transmission cool down.
If the transmission is operated at higher temperatures on
a frequent basis, see ªScheduled Maintenanceº in the
Index for the proper transmission maintenance intervals.LOW COOLANT
This message is displayed
when the cooling system is
low on coolant.
The engine may overheat. See ªEngine Coolantº in the
Index and have your vehicle serviced as soon as you can.
CHECK COOLANT TEMP
This message is displayed
when the cooling system
temperature gets hot.
Check the coolant temperature gage and the coolant
level. See ªEngine Coolantº and ªEngine Coolant
Temperature Gageº in the Index. See ªEngine
Overheatingº in the Index for further information.

3-23
AM-FM: Press this button to switch from a tape to
the radio.
TAPE AUX: Press this button to return to the tape
player when playing the radio. The lighted arrow will
appear and show the direction of play when a tape is in
the active mode.
EJECT: Press this button to remove the tape. The
radio will now play. EJECT can be used with either the
ignition or radio off. To load a cassette tape with the
ignition or radio off, press EJECT before loading
the cassette.
CLN: If this message appears on the display, the 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 the tapes and player. See ªCare of Your Cassette Tape
Playerº in the Index. 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.CD Adapter Kits
It is possible to use a portable CD player adapter kit
with your cassette tape player after activating the bypass
feature on your tape player.
To activate the bypass feature, 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, indicating the feature is active.
4. Insert the adapter into the cassette slot. It will
power up the radio and begin playing.
This override routine will remain active until EJECT
is pressed.

3-27
PREV (1): Press PREV or the SEEK left arrow to
search for the previous selection. If you hold this button
or press it more than once, the disc will advance further.
Sound is muted in this mode.
RDM (2): Press this button to play the tracks on the disc
in random order. While in the RDM mode, RANDOM
appears on the display. Press RDM again to return to
normal play.
NEXT (3): Press NEXT or the SEEK right arrow to
search for the next selection. If you hold this button or
press it more than once, the disc will advance further.
The next track number will appear on the display.
Sound is muted in this mode.
REV (4): Press and hold REV to return rapidly to a
favorite passage. You will hear the disc selection play at
high speed while you press the REV button. This allows
you to listen and find out when the disc is at the desired
selection. Release REV to resume playing.
FWD (6): Press and hold this button to advance rapidly
within a track. You will hear the disc selection play at
high speed while you press the FWD button. This allows
you to listen and find out when the disc is at the desired
selection. Release FWD to resume playing.RECALL: Press this button to see what track is playing.
Press it again within five seconds to see how long the
CD has been playing that track. Elapsed time is
displayed in minutes and seconds. The track number
will also appear when a new track begins to play. Press
RECALL again to return to the time display.
AM
-FM: While in the CD mode, press this button to
stop playing the CD and play the radio. The CD symbol
will still display but the word CD will be replaced with
either AM, FM1 or FM2. (If the radio is turned off,
the disc stays in the player and will resume playing at
the point where it stopped.)
CD AUX: To switch between the player and the radio
when a disc is playing, press the AM
-FM button.
To return to the player, press CD AUX. When a disc is
playing, the letters CD and the CD symbol will appear
on the display. (If the radio is turned off, the disc stays
in the player and will resume playing at the point where
it stopped.)
EJECT: Press this button to eject the disc from the
player and play the radio. When the same or a new
disc is inserted, the disc will start playing on track one.
If a compact disc is left sitting in the opening for more
than a few seconds, the player will pull the CD back in.
The radio will continue playing. When the ignition is
off, press this button to load a CD.

3-31
RANDOM: Press P.SCAN to enter the random play
mode. RANDOM will appear on the display. While in
this mode, the tracks on the disc 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.

3-35 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 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.

3-36
If your vehicle is equipped with the AM-FM Stereo with
Cassette Tape Player:
1. Turn the ignition to RUN or ACCESSORY.
2. Turn the radio on.
3. Insert the scrubbing action cleaning cassette.
4. 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 detection feature is no longer active.
5. Eject the cleaning cassette after the manufacturer's
recommended cleaning time.
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 make sure the cassette
tape is in good condition before you have your tape
player serviced.