Page 89 of 462

Not all manual downshift requests will be allowed by
the transmission. To prevent excessive engine RPMs,
each gear has a maximum vehicle speed associated
with it. Any downshift request above this speed is
not allowed by the transmission.
If shifting is prevented for any reason, the current
gear ashes multiple times in the Driver Information
Center (DIC), indicating that the transmission has
not shifted gears.
Some automatic downshifts can occur to maintain
minimum engine speed. This only happens if the vehicle
is left in too high of a gear for the vehicle’s speed.
For example, if you have been driving in sixth gear range
and come to a stop without manually downshifting, the
transmission automatically downshifts to rst gear and
displays rst gear on the HUD. As you begin to drive and
accelerate, the transmission remains in rst gear until the
driver selects an upshift.DSC can be used while using cruise control, but
transmission shifting is different while the cruise control
is on. This is not a malfunction and is necessary to
let proper operation of the cruise control.
To return to fully automatic operation, move the shift
lever to the right and back into D (Drive).
When accelerating the vehicle from a stop in snowy and
icy conditions, you may want to shift into second gear.
A higher gear allows you to gain more traction on slippery
surfaces.
In higher gears, on the XLR only, an automatic downshift
occurs if you press the accelerator pedal to the oor.
This feature provides adequate acceleration capabilities
if you forget to downshift manually. Tap the shifter
forward and the vehicle upshifts.
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Page 90 of 462

Parking Brake
The parking brake pedal is
located to the left of the
regular brake pedal,
near the driver door.
To set the parking brake, hold the regular brake pedal
down, then push the parking brake pedal down.
If the ignition is on, the parking brake indicator light on
the instrument panel cluster should come on. If it
does not, you need to have the vehicle serviced.When you move out of P (Park) or N (Neutral) and the
engine is running, the parking brake should release.
If the parking brake has not been fully released and you
try to drive off with the parking brake on, the parking
brake indicator light will come on and stay on.
If the parking brake does not fully release, you can
manually release the pedal.
{CAUTION:
Always shift to P (Park) before pulling the manual
release lever. If your hand or arm is in the way of
the pedal you could be hurt. The pedal springs
back quickly. Keep your hand and arm away when
you use the manual release lever.
Before releasing the manual parking brake, be sure to
put the vehicle in P (Park) and turn the ignition off.
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Page 91 of 462

Reach under the driver side of the instrument panel and
pull down on the manual release lever, which is located
behind the parking brake pedal. Pull down on the yellow
tab. If the parking brake does not release, you should
have the vehicle towed to your dealer/retailer for service.
Notice:Driving with the parking brake on can
overheat the brake system and cause premature
wear or damage to brake system parts. Make sure
that the parking brake is fully released and the brake
warning light is off before driving.
Shifting Into Park
{CAUTION:
It can be 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. 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, use the steps that follow.
1. Hold the brake pedal down and set the parking
brake.
SeeParking Brake on page 2-32for more
information.
2. Move the shift lever into P (Park) by pushing the
lever all the way toward the front of the vehicle.
3. Turn the ignition off.
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Page 92 of 462

Leaving the Vehicle With the Engine
Running
{CAUTION:
It can be dangerous to leave the vehicle with the
engine running. The vehicle could move suddenly if
the shift lever is not fully in P (Park) with the parking
brake rmly set. And, if you leave the vehicle with
the engine running, it could overheat and even
catch re. You or others could be injured. Do not
leave the vehicle with the engine running.
If you have to leave the vehicle with the engine running,
be sure the vehicle is in P (Park) and the parking brake is
rmly set before you leave it. After you have moved the
shift lever into P (Park), hold down the regular brake
pedal. See if you can move the shift lever away from
P (Park) without rst pulling it toward you. If you can, it
means that the shift lever was not fully locked into
P (Park).
Torque Lock
If you are parking on a hill and you do not shift the
transmission into P (Park) properly, the weight of the
vehicle may put too much force on the parking pawl in
the transmission. You may nd it difficult to pull the
shift lever out of P (Park). This is called “torque lock.”
To prevent torque lock, set the parking brake and
then shift into P (Park) properly before you leave the
driver seat. To nd out how, see “Shifting Into Park”
listed previously in this section.
When you are ready to drive, move the shift lever out of
P (Park) 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 P (Park).
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Page 93 of 462

Shifting Out of Park
Shift lock release prevents shifting out of P (Park)
unless the vehicle is running or in Accessory mode and
the brake pedal is applied.
The shift lock release is always functional except in
the case of an uncharged or low voltage (less than
9-volt) battery. SeeJump Starting on page 6-36for
more information.
To shift out of P (Park) use the following:
1. Apply the brake pedal.
2. Press the shift lever button.
3. Move the shift lever to the desired position.If you still are unable to shift out of P (Park):
1. Fully release the shift lever button.
2. While holding down the brake pedal, press the shift
lever button again.
3. Move the shift lever to the desired position.
If you still cannot move the shift lever from P (Park),
consult your dealer/retailer or a professional towing
service.
Parking Over Things That Burn
{CAUTION:
Things that can burn could touch hot exhaust
parts under the vehicle and ignite. Do not park
over papers, leaves, dry grass, or other things that
can burn.
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Page 94 of 462

Engine Exhaust
{CAUTION:
Engine exhaust contains Carbon Monoxide (CO)
which cannot be seen or smelled. Exposure to CO
can cause unconsciousness and even death.
Exhaust may enter the vehicle if:
The vehicle idles in areas with poor ventilation
(parking garages, tunnels, deep snow that may
block underbody air ow or tail pipes).
The exhaust smells or sounds strange or
different.
The exhaust system leaks due to corrosion or
damage.
CAUTION: (Continued)
CAUTION: (Continued)
The vehicle’s exhaust system has been
modi ed, damaged or improperly repaired.
There are holes or openings in the
vehicle body from damage or after-market
modi cations that are not completely sealed.
If unusual fumes are detected or if it is suspected
that exhaust is coming into the vehicle:
Drive it only with the windows
completely down.
Have the vehicle repaired immediately.
Never park the vehicle with the engine running in
an enclosed area such as a garage or a building
that has no fresh air ventilation.
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Page 95 of 462

Running the Vehicle While Parked
It is better not to park with the engine running. But if you
ever have to, here are some things to know.
{CAUTION:
Idling a vehicle in an enclosed area with poor
ventilation is dangerous. Engine exhaust may
enter the vehicle. Engine exhaust contains Carbon
Monoxide (CO) which cannot be seen or smelled.
It can cause unconsciousness and even death.
Never run the engine in an enclosed area that has
no fresh air ventilation. For more information, see
Engine ExhaustEngine Exhaust on page 2-36.
{CAUTION:
It can be dangerous to get out of the vehicle if
the automatic transmission 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).
Follow the proper steps to be sure the vehicle will not
move. SeeShifting Into Park on page 2-33.
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Page 96 of 462

Mirrors
Automatic Dimming Rearview Mirror
This vehicle has an automatic dimming inside rearview
mirror with OnStar®controls. SeeOnStar®System on
page 2-42for more information.
O(On/Off):Press to turn the dimming feature
on or off.
Automatic Dimming Mirror Operation
Automatic dimming reduces the glare of lights from
behind the vehicle. The dimming feature comes on and
the indicator light illuminates each time the vehicle is
started.
Cleaning the Mirror
Do not spray glass cleaner directly on the mirror. Use a
soft towel dampened with water.
Outside Power Mirrors
Controls for the outside
power mirrors are located
on the driver’s door
armrest.
1. Move
}or|(selector switches) to the left or right
to choose the driver’s or passenger side mirror.
2. Press one of the four edges located on the control
pad to move the mirror to the desired direction.
3. Adjust each outside mirror so that a little of the
vehicle and the area behind can be seen.
Keep the selector switch in the center position when not
adjusting either outside mirror.
Manually fold the mirrors inward by pulling them toward
the vehicle. This feature may be useful when going
through a car wash or a con ned space. Push the
mirrors away from the vehicle, to the normal position,
before driving.
2-38