1999 GMC SUBURBAN 4 wheel drive

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

1-31 How the Air Bag Systems Work
Where are the air bags?
The driver's frontal air bag is in the middle of the
steering wheel.
The right front passenger's frontal air bag is in the
instrument panel on the passenger's side.
The driver's side impact air bag is in the side of the
driver's seatback closest to the door.

1-33
When should an air bag inflate?
The driver's and right front passenger's frontal air bags
are designed to inflate in moderate to severe frontal or
near
-frontal crashes. The frontal air bags are designed
to inflate only if the impact speed is above the system's
designed ªthreshold level.º If your vehicle goes
straight into a wall that doesn't move or deform, the
threshold level is about 9 to 16 mph (14 to 26 km/h).
The threshold level can vary, however, with specific
vehicle design, so that it can be somewhat above or
below this range. If your vehicle strikes something
that will move or deform, such as a parked car, the
threshold level will be higher. The driver's and right
front passenger's frontal air bags are not designed
to inflate in rollovers, side impacts, or rear impacts,
because inflation would not help the occupant.
The side impact air bags are designed to inflate in
moderate to severe side crashes involving a front door.
A side impact air bag will inflate if the crash severity
is above the system's designed ªthreshold level.º
The threshold level can vary with specific vehicle
design. Side impact air bags are not designed to inflate
in frontal or near
-frontal impacts, rollovers or rear
impacts, because inflation would not help the occupant.
A side impact air bag will only deploy on the side of the
vehicle that is struck.In any particular crash, no one can say whether an air
bag should have inflated simply because of the damage
to a vehicle or because of what the repair costs were.
For frontal air bags, inflation is determined by the angle
of the impact and how quickly the vehicle slows down
in frontal and near
-frontal impacts. For side impact air
bags, inflation is determined by the location and severity
of the impact.
The air bag system is designed to work properly under
a wide range of conditions, including off
-road usage.
Observe safe driving speeds, especially on rough terrain.
As always, wear your safety belt. See ªOff
-Road
Drivingº in the Index for more tips on off
-road driving.
What makes an air bag inflate?
In an impact of sufficient severity, the air bag sensing
system detects that the vehicle is in a crash. For both
frontal and side impact air bags, the sensing system
triggers a release of gas from the inflator, which inflates
the air bag. The inflator, air bag and related hardware
are all part of the air bag modules inside the steering
wheel, instrument panel and the side of the front
seatbacks closest to the door.

1-34
How does an air bag restrain?
In moderate to severe frontal or near frontal collisions,
even belted occupants can contact the steering wheel
or the instrument panel. In moderate to severe side
collisions, even belted occupants can contact the inside
of the vehicle. The air bag supplements the protection
provided by safety belts. Air bags distribute the force of
the impact more evenly over the occupant's upper body,
stopping the occupant more gradually. But the frontal
air bags would not help you in many types of collisions,
including rollovers, rear impacts, and side impacts,
primarily because an occupant's motion is not toward
the air bag. Side impact air bags would not help you
in many types of collisions, including frontal or near
frontal collisions, rollovers, and rear impacts, primarily
because an occupant's motion is not toward those air
bags. Air bags should never be regarded as anything
more than a supplement to safety belts, and then only in
moderate to severe frontal or near
-frontal collisions for
the driver's and right front passenger's frontal air bags,
and only in moderate to severe side collisions for the
driver's and right front passenger's side impact air bags.What will you see after an air bag inflates?
After an air bag inflates, it quickly deflates, so quickly
that some people may not even realize the air bag
inflated. Some components of the air bag module
-- the
steering wheel hub for the driver's air bag, the instrument
panel for the right front passenger's bag, the side of the
seatback closest to the door for the driver and right front
passenger's side impact air bags
-- will be hot for a short
time. The parts of the bag that come into contact with you
may be warm, but not too hot to touch. There will be
some smoke and dust coming from the vents in the
deflated air bags. Air bag inflation doesn't prevent the
driver from seeing or being able to steer the vehicle,
nor does it stop people from leaving the vehicle.
CAUTION:
When an air bag inflates, there is dust in the air.
This dust could cause breathing problems for
people with a history of asthma or other breathing
trouble. To avoid this, everyone in the vehicle
should get out as soon as it is safe to do so. If you
have breathing problems but can't get out of the
vehicle after an air bag inflates, then get fresh air
by opening a window or a door.

1-35
In many crashes severe enough to inflate an air bag,
windshields are broken by vehicle deformation.
Additional windshield breakage may also occur from
the right front passenger air bag.

Air bags are designed to inflate only once. After an
air bag inflates, you'll need some new parts for your
air bag system. If you don't get them, the air bag
system won't be there to help protect you in another
crash. A new system will include air bag modules
and possibly other parts. The service manual for
your vehicle covers the need to replace other parts.

Your vehicle is equipped with a crash sensing and
diagnostic module, which records information about
the frontal air bag system. The module records
information about the readiness of the system, when
the system commands air bag inflation and driver's
safety belt usage at deployment. Some modules also
record speed, engine rpm, brake and throttle data.

Let only qualified technicians work on your air bag
systems. Improper service can mean that an air
bag system won't work properly. See your dealer
for service.
NOTICE:
If you damage the covering for the driver's or
the right front passenger's air bag, or the air
bag covering on the driver's and right front
passenger's seatback, the bag may not work
properly. You may have to replace the air bag
module in the steering wheel, both the air bag
module and the instrument panel for the right
front passenger's air bag, or both the air bag
module and seatback for the driver's and right
front passenger's side impact air bag. Do not
open or break the air bag coverings.

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

2-11
To open the driver's side panel door, first open the
passenger's side door. Then, pull the handle on the left
door edge out and pull the door open.
To close the doors, close the driver's side door first.
After securely closing the door, close the passenger's
side door. Make sure both doors are latched securely.
To lock the rear doors from outside the vehicle, put your
key in the lock and turn it clockwise. If you have power
door locks, you can lock the side doors as well as the rear
doors from inside the vehicle. For more information,
see ªPower Door Locksº earlier in this section.
Theft
Vehicle theft is big business, especially in some cities.
Although your vehicle has a number of theft
-deterrent
features, we know that nothing we put on it can make it
impossible to steal. However, there are ways you can help.
Key in the Ignition
If you leave your vehicle with the keys inside, it's an
easy target for joy riders or professional thieves
-- so
don't do it.
When you park your vehicle and open the driver's door,
you'll hear a chime reminding you to remove your key
from the ignition and take it with you. Always do this.Your steering wheel will be locked, and so will your
ignition and transmission. Also remember to lock
the doors.
If the key is in the ignition, with any door open, and you
try to lock your doors with the power door locks, the
driver's door will not stay locked. This will help to keep
you from locking your keys in the vehicle.
Parking at Night
Park in a lighted spot, close all windows and lock your
vehicle. Remember to keep your valuables out of sight.
Put them in a storage area, or take them with you.
Parking Lots
If you park in a lot where someone will be watching
your vehicle, it's best to lock it up and take your keys.
But what if you have to leave your ignition key? What if
you have to leave something valuable in your vehicle?

Put your valuables in a storage area, like your
glove box.

Valuables can be locked in the center floor console.

If your vehicle has a remote keyless entry system,
take the transmitter with you.

Lock all the doors except the driver's.

2-14
New Vehicle ªBreak-Inº
NOTICE:
Your vehicle doesn't need an elaborate
ªbreak
-in.º But it will perform better in the
long run if you follow these guidelines:

Keep your speed at 55 mph (88 km/h) or
less for the first 500 miles (805 km).

Don't drive at any one speed
-- fast or
slow
-- for the first 500 miles (805 km).
Don't make full
-throttle starts.

Avoid making hard stops for the first
200 miles (322 km) or so. During this time
your new brake linings aren't yet broken
in. Hard stops with new linings can mean
premature wear and earlier replacement.
Follow this breaking
-in guideline every
time you get new brake linings.

Don't tow a trailer during break
-in.
See ªTowing a Trailerº in the Index for
more information.
Ignition Positions
You can use your key to turn your ignition switch to five
different positions.
ACCESSORY (A): ACCESSORY lets you use things
like the radio, power windows and the windshield wipers
when the engine is off. Push in the key and turn it toward
you. Your steering wheel will remain locked, just as it
was before you inserted the key.
LOCK (B): This position locks your ignition, steering
wheel and transmission. It's a theft
-deterrent feature.
You will only be able to remove your key when the
ignition is turned to LOCK.