
When you want to open a rear door when the security
lock is on, do the following:
1. Unlock the door by lifting the rear door manual lock,
using the power door lock switch, or the Remote
Keyless Entry (RKE) transmitter, if the vehicle
has one.
2. Open the door from the outside.
To cancel the rear door security lock, do the following:
1. Unlock the door and open it from the outside.
2. Insert the key into the security lock slot and turn it
so the slot is in the vertical position.
Lockout Protection
This feature protects you from locking your key in the
vehicle when the key is in the ignition and a door
is open.
If the power lock switch is pressed when a door is open
and the key is in the ignition, all of the doors will lock
and then the driver’s door will unlock.
Midgate®
{CAUTION:
It can be dangerous to drive with the cargo area
covered and the tailgate and the Midgate®open
because carbon monoxide (CO) gas can come
into your vehicle. You can not see or smell CO. It
can cause unconsciousness and even death. If
you must drive with the cargo covers on and the
tailgate and Midgate
®open or if electrical wiring or
other cable connections must pass through the
seal between the body and the Midgate
®:
Make sure all windows are shut.
Turn the fan on your heating or cooling
system to its highest speed on the setting that
brings in outside air. This will force outside air
into your vehicle. SeeDual Automatic Climate
Control System on page 3-22.
If you have air outlets on or under the
instrument panel, open them all the way. See
Engine Exhaust on page 2-45.
2-11

If the engine does not start and the security light on the
instrument panel cluster comes on when trying to
start the vehicle, there may be a problem with your
theft-deterrent system. Turn the ignition off and try again.
If the engine still does not start, and the key appears
to be undamaged, try another ignition key. At this time,
you may also want to check the fuse, seeFuses
and Circuit Breakers on page 6-103. If the engine still
does not start with the other key, your vehicle needs
service. If your vehicle does start, the rst key may be
faulty. See your dealer/retailer who can service the
PASS-Key
®III+ to have a new key made. In an
emergency, contact Roadside Assistance.
It is possible for the PASS-Key
®III+ decoder to learn
the transponder value of a new or replacement key. Up
to 10 keys may be programmed for the vehicle. The
following procedure is for programming additional keys
only. If all the currently programmed keys are lost or
do not operate, you must see your dealer/retailer
or a locksmith who can service PASS-Key
®III+ to have
keys made and programmed to the system.See your dealer/retailer or a locksmith who can service
PASS-Key
®III+ to get a new key blank that is cut
exactly as the ignition key that operates the system.
To program the new additional key:
1. Verify that the new key has a
1stamped on it.
2. Insert the original, already programmed, key in the
ignition and start the engine. If the engine will not
start, see your dealer/retailer for service.
3. After the engine has started, turn the key to
LOCK/OFF, and remove the key.
4. Insert the new key to be programmed and turn it to
the ON/RUN position within ve seconds of turning
the ignition to the LOCK/OFF position in Step 3.
The security light will turn off once the key has been
programmed.
5. Repeat Steps 1 through 4 if additional keys are to
be programmed.
If you lose or damage your PASS-Key
®III+ key, see
your dealer/retailer or a locksmith who can service
PASS-Key
®III+ to have a new key made.
Do not leave the key or device that disarms or
deactivates the theft deterrent system in the vehicle.
2-30

Notice:Using a tool to force the key to turn in the
ignition could cause damage to the switch or break
the key. Use the correct key, make sure it is all the
way in, and turn it only with your hand. If the key
cannot be turned by hand, see your dealer/retailer.
B (ACC/ACCESSORY):This position lets things like the
radio and the windshield wipers operate while the
engine is off. Use this position if the vehicle must be
pushed or towed.
C (ON/RUN):This position can be used to operate the
electrical accessories and to display some instrument
panel cluster warning and indicator lights. The
switch stays in this position when the engine is running.
The transmission is also unlocked in this position on
automatic transmission vehicles.
If you leave the key in the ACC/ACCESSORY or
ON/RUN position with the engine off, the battery could
be drained. You may not be able to start the vehicle
if the battery is allowed to drain for an extended period
of time.
D (START):This is the position that starts the engine.
When the engine starts, release the key. The ignition
switch returns to ON/RUN for driving.
A warning tone will sound when the driver door is
opened, the ignition is in ACC/ACCESSORY or
LOCK/OFF and the key is in the ignition.Retained Accessory Power (RAP)
The following vehicle accessories can be used for up to
10 minutes after the engine is turned off:
Audio System
Power Windows
OnStar®System (if equipped)
Sunroof (if equipped)
These features work when the key is in ON/RUN or
ACC/ACCESSORY. Once the key is turned from
ON/RUN to LOCK/OFF, the windows and sunroof
continue to work up to 10 minutes until any door
is opened. The radio continues to work for up to
10 minutes or until the driver door is opened.
Starting the Engine
Move the shift lever to P (Park) or N (Neutral). The
engine will not start in any other position. To restart the
engine when the vehicle is already moving, use
N (Neutral) only.
Notice:Do not try to shift to P (Park) if the vehicle
is moving. If you do, you could damage the
transmission. Shift to P (Park) only when the vehicle
is stopped.
2-32

Automatic Transmission Operation
The vehicle has a Hydra-Matic®6L80 automatic
transmission, and has an electronic shift position
indicator within the instrument panel cluster. The
electronic shift position indicator displays when the
shift lever is moved out of P (Park).
There are several different positions for the shift lever.
P (Park):This position locks the rear wheels. It is the
best position to use when you start the engine because
the vehicle cannot move easily.
When parked on a hill, especially when the vehicle has
a heavy load, you may notice an increase in the
effort to shift out of P (Park). See Torque Lock
(Automatic Transmission) underShifting Into Park on
page 2-43for more information.{CAUTION:
It is dangerous to get out of the vehicle if the shift
lever is not fully in P (Park) with the parking brake
rmly set. The vehicle can roll.
Do not leave the vehicle when the engine is
running unless you have to. If you have left the
engine running, the vehicle can move suddenly.
You or others could be injured. To be sure the
vehicle will not move, even when you are on fairly
level ground, always set the parking brake and
move the shift lever to P (Park). SeeShifting Into
Park on page 2-43. If you are pulling a trailer, see
Towing a Trailer on page 5-40.
R (Reverse):Use this gear to back up.
Notice:Shifting to R (Reverse) while the vehicle is
moving forward could damage the transmission.
The repairs would not be covered by the vehicle
warranty. Shift to R (Reverse) only after the vehicle
is stopped.
2-36