automatic transmission GMC SUBURBAN 1999 Owner's Manual

Table of Contents
Keys and Door Locks
Keyless Entry System (If Equipped)
Liftgate
Automatic Transmission Operation
Four-Wheel Drive (If Equipped)
Parking Brake
Windows
Tilt Wheel (If Equipped)
Turn Signal/Multifunction Lever
Windshield Wipers
Cruise ControlInterior and Exterior Lamps
Mirrors
Storage Compartments
Convenience Net/Cargo Cover/Luggage Carrier (If Equipped)
Accessory Power Outlets
OnStar® System (If Equipped)
Sunroof (If Equipped)
HomeLink® Transmitter (If Equipped)
Instrument Panel, Warning Lights and Gages
Message Center Seats and Seat Controls
Safety BeltsAir Bag Systems
Child Restraints
Section
1
Section
2
Seats and Restraint Systems
Features and Controls
ii

2-
2-1
Section 2 Features and Controls
Here you can learn about the many standard and optional features on your vehicle, and information on starting,
shifting and braking. Also explained are the instrument panel and the warning systems that tell you if everything is
working properly
-- and what to do if you have a problem.
2
-2 Keys
2
-3 Door Locks
2
-7 Keyless Entry System (If Equipped)
2
-11 Theft
2
-12 Content Theft-Deterrent (If Equipped)
2
-13 Passlock

2-14 New Vehicle ªBreak Inº
2
-14 Ignition Positions
2
-15 Starting Your Engine
2
-17 Engine Coolant Heater (If Equipped)
2
-18 Automatic Transmission Operation
2
-22 Four-Wheel Drive (If Equipped)
2
-27 Parking Brake
2
-28 Shifting Into PARK (P)
2
-30 Shifting Out of PARK (P)
2
-31 Parking Over Things That Burn
2
-31 Engine Exhaust2
-32 Running Your Engine While You're Parked
2
-33 Level Control (If Equipped)
2
-34 Autoride (If Equipped)
2
-34 Locking Rear Axle
2
-34 Windows
2
-36 Turn Signal/Multifunction Lever
2
-43 Exterior Lamps
2
-46 Interior Lamps
2
-48 Mirrors
2
-55 Storage Compartments
2
-62 HomeLink
Transmitter (If Equipped)
2
-65 OnStar
System (If Equipped)
2
-66 The Instrument Panel - Your
Information System
2
-68 Instrument Panel Cluster
2
-69 Warning Lights, Gages and Indicators
2
-82 Message Center

2-18
CAUTION:
Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the wrong
kind of extension cord could overheat and cause
a fire. You could be seriously injured. Plug the
cord into a properly grounded three
-prong
11 0
-volt AC outlet. If the cord won't reach,
use a heavy
-duty three-prong extension cord
rated for at least 15 amps.
4. Before starting the engine, be sure to unplug and store
the cord as it was before to keep it away from moving
engine parts. If you don't, it could be damaged.
How long should you keep the coolant heater plugged
in? The answer depends on the outside temperature, the
kind of oil you have, and some other things. Instead of
trying to list everything here, we ask that you contact
your dealer in the area where you'll be parking your
vehicle. The dealer can give you the best advice for
that particular area.
Automatic Transmission Operation
There are several different positions for your shift lever.
Your vehicle is equipped with an automatic transmission
and features an electronic shift position indicator within
the instrument panel cluster. This display must be
powered anytime the shift lever is capable of being
moved out of PARK (P). This means that if your key is
in OFF, rather than LOCK, there will be a small current
drain on your battery which could discharge your battery
over a period of time. If you have to leave your key in
the ignition in OFF for an extended period, it is
recommended that you remove the IGN 0 fuse from the
instrument panel fuse block. See ªFuses and Circuit
Breakersº in the Index.

2-21
THIRD (3): This position is also used for normal
driving, however it offers more power and lower fuel
economy than DRIVE (D).
SECOND (2): This position gives you more power but
lower fuel economy. You can use SECOND (2) on hills.
It can help control your speed as you go down steep
mountain roads, but then you would also want to use
your brakes off and on.
If you manually select SECOND (2) in a light duty
automatic transmission, the transmission will drive in
second gear. You may use this feature for reducing the
speed of the rear wheels when you are trying to start
your vehicle from a stop on slippery road surfaces.
FIRST (1): This position gives you even more power
(but lower fuel economy) than SECOND (2). You can
use it on very steep hills, or in deep snow or mud. If the
selector lever is put in FIRST (1) while the vehicle is
moving forward, the transmission won't shift into first
gear until the vehicle is going slowly enough.
NOTICE:
If your rear wheels can't rotate, don't try to
drive. This might happen if you were stuck in
very deep sand or mud or were up against a solid
object. You could damage your transmission.
Also, if you stop when going uphill, don't hold
your vehicle there with only the accelerator
pedal. This could overheat and damage the
transmission. Use your brakes or shift into
PARK (P) to hold your vehicle in position
on a hill.
On cold days, approximately 32
F (0
C) or colder,
your transmission is designed to shift differently until
the engine reaches normal operating temperature.
This is intended to improve heater performance.

2-24
AUTO 4WD: This setting is ideal for use when road
conditions are variable. When driving your vehicle in
AUTO 4WD, the front axle is engaged, but the vehicle's
power is sent only to the rear wheels. When the vehicle
senses a loss of traction, the system will automatically
engage four
-wheel drive. Driving in this mode results in
slightly lower fuel economy than 2HI.
4HI: Use 4HI when you need extra traction, such as
on snowy or icy roads or in most off
-road situations.
This setting also engages your front axle to help drive
your vehicle. This is the best setting to use when
plowing snow.
4LO: This setting also engages your front axle and
delivers extra torque. You may never need 4LO. It sends
maximum power to all four wheels. You might choose
4LO if you are driving off
-road in deep sand, deep mud,
deep snow and climbing or descending steep hills.
CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the transmission
is in PARK (P). You or someone else could be
seriously injured. Be sure to set the parking
brake before placing the transfer case in
NEUTRAL. See ªParking Brakeº in the Index.
NEUTRAL: Shift the vehicle's transfer case to NEUTRAL
only when towing your vehicle. See ªRecreational Vehicle
Towingº or ªTowing Your Vehicleº in the Index for
more information.
Indicator lights in the switches show which setting you are
in. The indicator lights will come on briefly when you turn
on the ignition and one will stay on. If the lights do not
come on, you should take your vehicle to your dealer for
service. An indicator light will flash while shifting the
transfer case. It will remain illuminated when the shift is
complete. If for some reason the transfer case cannot make
a requested shift, it will return to the last chosen setting.

2-30
If you have to leave your vehicle with the engine
running, be sure your vehicle is in PARK (P) and the
parking brake is firmly set before you leave it. After you
move the shift lever into PARK (P), hold the regular
brake pedal down. Then, see if you can move the shift
lever away from PARK (P) without first pulling it
toward you. If you can, it means that the shift lever
wasn't fully locked into PARK (P).
Torque Lock
If you are parking on a hill and you don't shift your
transmission into PARK (P) properly, the weight of the
vehicle may put too much force on the parking pawl in
the transmission. You may find it difficult to pull the
shift lever out of PARK (P). This is called ªtorque lock.º
To prevent torque lock, set the parking brake and then
shift into PARK (P) properly before you leave the
driver's seat. To find out how, see ªShifting Into
PARK (P)º in the Index.
When you are ready to drive, move the shift lever out
of PARK (P) before you release the parking brake.
If torque lock does occur, you may need to have another
vehicle push yours a little uphill to take some of the
pressure from the parking pawl in the transmission,
so you can pull the shift lever out of PARK (P).
Shifting Out of PARK (P)
Your vehicle has an automatic transmission shift lock
control system. You have to fully apply your regular
brakes before you can shift from PARK (P) when the
ignition is in RUN. See ªAutomatic Transmissionº in
the Index.
If you cannot shift out of PARK (P), ease pressure on
the shift lever and push the shift lever all the way up
into PARK (P) as you maintain brake application.
Then, move the shift lever into the gear you want.
If you ever hold the brake pedal down but still can't
shift out of PARK (P), try this:
1. Turn the key to the OFF ignition position.
2. Apply and hold the brake until the end of Step 4.
3. Shift the vehicle to NEUTRAL (N).
4. Start the vehicle and then shift to the drive gear
you want.
5. Have the system fixed as soon as you can.

2-44
Your vehicle is equipped with a light sensor located on
the top of the instrument panel in the defroster grille. Be
sure it is not covered, or the system will be on whenever
the ignition is on.
The system may also turn on your headlamps when
driving through a parking garage, heavy overcast
weather or a tunnel. This is normal.
There is a delay in the transition between the daytime
and nighttime operation of the Daytime Running
Lamps (DRL) and the automatic headlamp systems
so that driving under bridges or bright overhead street
lights does not affect the system. The DRL and
automatic headlamp system will only be affected when
the light sensor sees a change in lighting lasting longer
than the delay.
To idle your vehicle with the automatic headlamp
system off, set the parking brake while the ignition is
off. Then start your vehicle. The automatic headlamp
system will stay off until you release the parking brake.
As with any vehicle, you should turn on the regular
headlamp system when you need it.
You may be able to turn off your Automatic Headlamp
System. See ªDaytime Running Lamps (DRL)º later in
this section for more information.Lamps On Reminder
A reminder chime will sound when your headlamps or
parking lamps are manually turned on and your ignition
is in OFF, LOCK or ACCESSORY. To disable the
chime, rotate the thumbwheel all the way down. In the
automatic mode, the headlamps turn off once the
ignition key is in OFF.
Daytime Running Lamps
Daytime Running Lamps (DRL) can make it easier for
others to see the front of your vehicle during the day.
DRL can be helpful in many different driving
conditions, but they can be especially helpful in the
short periods after dawn and before sunset.
The DRL system will come on when:

the ignition is on,

the headlamp switch is in automatic headlamp mode,

the automatic transmission is not in PARK (P),

the light sensor determines it is daytime and

the parking brake is released.
When the DRL are on, only your DRL lamps will be on.
The taillamps, sidemarker and other lamps won't be on.
The instrument panel won't be lit up either.

2-45
When it begins to get dark, the automatic headlamp
system will switch from DRL to the headlamps or the
last chosen headlamp setting that was used.
When you turn the headlamp switch off, the headlamps
will go off, and your DRL lamps will illuminate,
provided it is not dark outside.
To idle an automatic transmission equipped vehicle with
the DRL off, set the parking brake. Shifting the
transmission into PARK (P) will also allow you to idle
the vehicle with the DRL off. The DRL will stay off
until you release the parking brake or shift the
transmission out of PARK (P).
The following procedure applies only to vehicles first
sold in the United States, and it does not apply to some
early production vehicles.
When necessary, you may turn off the Automatic Headlamp
System and the Daytime Running Lamps (DRL) feature by
following the steps below. When system is turned off the
headlights will not automatically come on when it becomes
dark outside. As with any vehicle, you should turn on the
regular headlamp system when you need it.
1. With the ignition in the RUN position.
2. Press the DOME OVERRIDE button four times
within six seconds. A chime will sound informing you
the Automatic Headlamp System and Daytime
Running Lamps are off.3. The system will revert back to the automatic mode
when the DOME OVERRIDE button is again pushed
four times within six seconds (chime will sound), or
when the ignition is turned off and on again.
Fog Lamps (If Equipped)
If you have fog lamps, use them for better vision in foggy
or misty conditions. Your parking lamps and/or low
-beam
headlamps must be on for your fog lamps to work.
The fog lamp switch is
located on the left side of
the instrument panel.
Press the switch to turn the fog lamps on. Press the
switch again to turn them off. An indicator light will
glow in the switch when the fog lamps are on.
Remember, fog lamps alone will not give off as much
light as your headlamps. Never use your fog lamps in
the dark without turning on your headlamps.

2-74 Engine Coolant Temperature Gage
United States Canada
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 250
F (122
C) mark. If the
gage reaches the 260
F (125
C) mark, it indicates that
the cooling system is working beyond its capacity.
The ªProblems on the Road,º section of this manual shows
what to do. See ªEngine Overheatingº in the Index.
Transmission Temperature Gage (If Equipped)
United States Canada
If your vehicle has a heavy duty automatic transmission,
you will have a transmission temperature gage.
When your ignition is on, the gage shows the temperature
of the transmission fluid. The normal operating range is
from 100
F (38
C) to about 265
F (130
C).
At approximately 265
F (130
C), the message center
will display a TRANS FLUID HOT message and the
transmission will enter a transmission protection mode.
When the transmission enters the protection mode, you
may notice a change in the transmission shifting patterns.
The transmission will return to normal shifting patterns
when the transmission fluid temperature falls below
260
F (127
C).

2-83 BATTERY
If this message is displayed
when the engine is running,
you may have a problem
with your charging system.
The battery display will also stay on while the key is in
RUN until the engine is started.
If the message stays on after starting the engine it could
indicate a problem with the generator drive belt, or some
other charging system problem. Have it checked right
away. Driving with this message displayed could drain
your battery.
If you must drive a short distance with this message
displayed, it helps to turn off all your accessories,
such as the radio and the air conditioner.
TRANS FLUID HOT
If you have an automatic transmission, you have a
transmission temperature warning display contained in
the message center.
If the transmission fluid
temperature becomes high,
the message center will
display this message.
When the transmission enters the protection mode,
you may notice a change in the transmission shifting
patterns. When the transmission fluid temperature
returns to normal, the display will turn off and the
transmission shifting patterns will return to normal.
NOTICE:
If you keep driving your vehicle with the
transmission TRANS FLUID HOT message
displayed, you can damage the transmission.
This could lead to costly repairs that may not
be covered under your warranty.