1998 GMC SIERRA ECO mode

If you are towing a trailer and are parking on any hill,
see “Towing a Trailer” in the Index. That section shows
what to do first
to keep the trailer from moving.
Shifting Into PARK (P) (Automatic
Transmission Only)
If you have a 3500 HD model, it is recommended that
the propshaft mounted parking brake be burnished
as
part of the new vehicle break-in. The parking brake
will work best after
it has been burnished following
these instructions.
Make
10 stops, using the parking brake foot pedal, from
20 mph (32 kmh) about 2 1/2 miles (4 km) apart. In
between stops, drive the vehicle at
20 mph (32 km/h).
A CAUTION:
-
It can be dangerous to get out of your vehicle if
the shift lever is not fully in PARK (P) with the
parking brake firmly
set. Your vehicle can roll.
If you have left the engine running, the vehicle can
move suddenly. You
or others could be injured. To
be sure your vehicle won’t move, even when you’re
on fairly level ground, use the steps that follow.
If
you have fourwheel drive and your transfer case is
in
NEUTRAL (N), your vehicle will be free to roll,
even
if your shift lever is in PARK (P). So, be sure
the transfer case is in a drive gear
-- not in
NEUTRAL (N). If you’re pulling a trailer, see
“Towing a Trailer” in the Index.
2-26
ProCarManuals.com

Crew Cab
If you have the optional power windows, the controls
are on each of the side doors.
The driver’s door has a switch for the passenger
windows as well. Your power windows will work when
the ignition has been turned
to ACCESSORY or RUN. Press the rear
of the
switch with the power window
symbol on
it to lower the window.
Press the front of
the switch with the power window
symbol
on it to raise the window.
The driver’s window also has an express down feature
that allows the window to be lowered without holding
the switch. Press and hold the side of the window switch
marked
AUTO for one second to activate the express
down mode. The express down mode can be canceled at
any time by pressing the opposite side
of the switch. To
open the window partway, lightly tap the switch until the
window is at the desired position.
Lockout Switch (Crew Cab)
If you have a Crew Cab and power windows, the power
window switch has
a lockout feature. This feature
prevents the rear windows from operating when
the
front driver’s side switch is in LOCK. The windows can
still be operated using the driver’s window switch.
When the switch is moved
to NORM, the rear power
windows will operate again.
2-33
ProCarManuals.com

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.
2-73
ProCarManuals.com

Mode Knob
The right knob on the control panel allows you to
choose the direction
of air delivery. The control knob
can be placed in any position between two mode settings
to blend the flow of air.
+e
/$ VENT This setting directs air through the
instrument panel outlets.
+’ VENT/HEAT Use this setting to divide airflow
between the floor outlets and instrument panel outlets.
+’ HEATER: This setting directs air through the
+e
0
heater floor outlets.
+’ DEFOG: This setting directs air to the heater
we
outlets and toward the windshield.
DEFROST This setting directs air toward the
windshield.
Air Conditioning
On hot days, open the windows long enough to let hot
air inside escape. This reduces the titne
it takes for your
vehicle to cool down. Then keep your windows closed
for the air conditioner to work its best. The recirculation button, between the
fan and
temperature
knobs, allows the air inside your vehicle to
be recirculated. This setting helps to maximize your air
conditioner’s performance and your vehicle’s fuel
economy. This setting also cools the air the fatest and
can be used
to keep unwanted odors and/or dust from
entering the vehicle. When using the air conditioner,
turn off recirculation after the vehicle reaches
a
comfortable interior temperature. When the right knob
on the control panel is between HEATER and
DEFROST, the recirculation feature will not function.
The A/C button, between the temperature and mode
knobs, allows the air coming into your vehicle to be
cooled. This setting is useful for normal cooling on hot
days. When you use
A/C with the recirculation button
pushed
in, turn off recirculation as soon as the vehicle
reaches
a comfortable interior temperature.
With the A/C
on, move the temperature knob to MAX
for maximum cooling. This setting also puts the system
in the recirculation mode and helps to maximize your air
conditioner‘s performance and your vehicle’s fuel
economy. This setting also cools the air the Fdstest. After
the vehicle‘s interior reaches
a comfortable temperature,
move the temperature knob to the right, to place the air
conditioning system
in the normal mode.
3-4
ProCarManuals.com

.
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
3-7
ProCarManuals.com

SCAN: Press and hold SEEK for two seconds until
SCAN appears on the display. SCAN allows you to
listen to stations for a few seconds. The receiver will
continue to scan and momentarily stop at each station
until you press the button again. The sound will mute
while scanning.
PUSHBUTTONS: The six numbered pushbuttons let
you return to your favorite stations. You can set up to
I8 stations (six AM, six FM 1 and six FM2). Just:
1. Turn the radio on.
2. Press AM-FM to select the band.
3. Tune in the desired station.
4. Press AUTO TONE to select the setting you prefer.
5. Press and hold one of the six pushbuttons. The sound
will mute. When it returns, release the button.
Whenever you press that numbered button, the
station you set
will return and the tone you selected
will be automatically selected for that button.
6. Repeat the steps for each pushbutton.
P. SCAN: The preset scan button lets you scan through
your favorite stations stored on your pushbuttons. Select
either the AM, FM
1 or FM2 mode and then press
P. SCAN. It will scan through each station stored
on
your pushbuttons and stop for a few seconds before continuing
to scan through
all of the pushbuttons. Press
P. SCAN again or one of the pushbuttons to stop
scanning
to listen to a specific preset station. P. SCAN
will light up on the display while in this mode. If one of
the stations stored on a pushbutton is too weak for the
location you are in, the radio display will show the
channel number (P
1 -P6) for several seconds before
advancing to the next preset station.
Setting the Tone
BASS:
Press lightly on this knob to release it from its
stored position. Turn
the knob to the right to increase bass
and
to the left to decrease bass. When the BASS control is
rotated, the AUTO TONE display will go blank.
TREB: Press lightly on this knob to release it from its
stored position. Turn the knob to the right to increase
treble and
to the left to decrease treble. When the TREB
control is rotated, the AUTO TONE display will go
blank.
If a station is weak or noisy, you may want to
decrease the treble.
Push these knobs back into their stored positions when
you’re not using them.
AUTO TONE: Press this button to select among the six
preset equalization settings and tailor the sound to the
music or voice being heard. Each time
you press the
button, the selection will switch to
one of the preset
ProCarManuals.com

settings of CLASSIC, NEWS, ROCK, POP, C/W
(CountryNestern) or JAZZ, To return
to the manual
mode, press and release this button
until the AUTO
TONE display goes blank. This will return the tone
adjustment to
the BASS and TREB controls. If a
BASS or TREB control is rotated, the AUTO TONE
display will
go blank. Use PUSHBUTTONS to program
AUTO TONE.
Adjusting the Speakers
BAL: Press lightly on this knob to release it from its
stored position. Turn the control to the right to ad-just
sound to the right speakers and to the left
to adjust
sound to the left speakers.
The middle position balances
the sound between the speakers.
FADE: Press lightly on this knob to release it from its
stored position. Turn the control to the right to adjust the
sound to the front speakers and to
the left for the rear
speakers. The middle position balances the sound
between the speakers.
Push these knobs back into their stored positions
when
you’re not using them.
Playing a Cassette Tape
Your tape player is built to work best with tapes that are
30 to 45 minutes long on each side. Tapes longer than
that are
so thin they may not work well in this player.
To load a cassette tape with the ignition off, press
EJECT or RECALL. Then, insert the cassette tape.
If the ignition is on but the radio is off, the tape will
begin playing.
Once the tape is playing, use the
VOL, AUTO TONE,
BAL, FADE, BASS and TREB controls just as you do
for the radio. The tape symbol and
a direction arrow will
be on the display whenever
a tape is being played.
Anytime a tape is inserted, the top side is selected for
play first.
The player automatically senses
if the cassette tape is
metal or Cr02 and adjusts for best playback sound.
For metal tapes, the double-D symbol will appear on
the display.
PREV (I): Press the PREV button or the SEEK left
arrow to search
for the previous selection. A minimum
three-second blank gap is required for the player
to stop
at the beginning of the selection. The tape direction
arrow
will blink during the SEEK operation.
PROG (2): Press this button to switch from one side of
the tape to the other.
NEXT (3): Press the NEXT button or the SEEK right
arrow
to search for the next selection. A mininlum
three-second blank gap is required for the player to stop
at the beginning of the selection. The tape direction
arrow
will blink during the SEEK operation. The sound
will mute while searching for the next selection.
3-14
ProCarManuals.com

REV (4): Press this button to rapidly reverse the tape to
the beginning of the cassette or
until you press REV
again. The radio will play the last selected station while
reversing the tape. The tape direction arrow
will blink
during
the reverse operation.
00 (5): Press this button to reduce cassette tape noise.
The double-D symbol
will appear on the display while
the player is
in this mode.
Dolby Noise Reduction is manufactured under a license
from Dolby Laboratories Licensing Corporation. Dolby
and the double-D symbol are trademarks of Dolby
Laboratories Licensing Corporation.
FWD (6): Press this button to rapidly forward the tape
to the end of the cassette or until you press FWD again.
The radio will play the last selected station while
forwarding the tape. The tape direction arrow will blink
during the forward operation.
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 ~rsed 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 “Care of
Your Cassette Tape Player”
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 CD 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 your 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 that the feature is active.
4. Insert the adapter. It will power up the radio and
begin playing.
This override routine will remain active
until EJECT
is pressed.
3-15
ProCarManuals.com