brake CADILLAC STS 2009 1.G Service Manual

Stability control activates when the computer senses a
difference between the intended path and the direction
the vehicle is actually traveling. Stability control
automatically adjusts the front road wheel steering
angle, modies the suspension stiffness, and selectively
applies braking pressure at any one of the vehicle’s
brakes to help maintain directional control of the vehicle.
When the system activates, a STABILITY SYS
ACTIVE message displays on the Driver Information
Center (DIC). SeeDIC Warnings and Messages
on page 3-79. It is normal to hear a noise or feel
vibration in the brake pedal when the system is working.
Continue to steer the vehicle in the intended direction.
If cruise control is engaged when Enhanced StabiliTrak
activates, the cruise control will automatically disengage.
Cruise Control may be re-engaged when road conditions
allow. SeeCruise Control on page 3-16,orAdaptive
Cruise Control on page 3-20for more information.
Enhanced StabiliTrak comes on automatically in the
Stability Touring Mode, when the vehicle is started.
The Stability Touring Mode is recommended for normal
driving. Enhanced StabiliTrak also has Stability
Competitive Mode that is turned on by pressing the
Traction Control (TC) button twice quickly. This mode is
designed to be used by the performance consciousdriver who desires less stability control intervention.
SeeCompetitive Driving Mode on page 4-11. When the
Stability Control Competitive Mode has been activated,
traction control operates in competitive mode and
cannot be turned off. The STABILITY COMPETITIVE
MODE message will be displayed on the DIC.
SeeDIC Warnings and Messages on page 3-79.
When operating the vehicle in the Stability Competitive
Mode, the system provides less stability control
intervention. Driving should be adjusted accordingly.
When the Stability Competitive Mode has been selected,
the Active Steering and Magnetic Ride Control Touring
Mode is not available. These systems are automatically
changed to the Performance Mode, providing more
response to road conditions and quicker steering
response. For more information, see “Active Steering
and Magnetic Ride Control Mode” in the Index of
the vehicle’s Navigation Manual.
To assist with directional control of the vehicle, always
leave the system on. Stability control can be turned
off however, by using the TC button. SeeTraction
Control System (TCS) on page 4-10. The STABILITY
SYS OFF message will be displayed on the DIC.
SeeDIC Warnings and Messages on page 3-79.
4-7

Traction Control System (TCS)
The vehicle has a traction control system that limits
wheel spin. This is especially useful in slippery road
conditions. On a rear-wheel-drive vehicle, the system
operates if it senses that one or both of the rear wheels
are spinning or beginning to lose traction. On an
All-Wheel-Drive (AWD) vehicle, the system will operate if
it senses that any of the wheels are spinning or beginning
to lose traction. When this happens, the system brakes
the spinning wheel(s) and/or reduces engine power to
limit wheel spin.
The system may be heard or felt while it is working, but
this is normal.
This warning light comes
on if there is a problem
with TCS.SeeTraction Control System (TCS) Warning Light on
page 3-63. When this warning light is on, the system will
not limit wheel spin. Adjust your driving accordingly.
TCS automatically comes on whenever the vehicle is
started. To limit wheel spin, especially in slippery
road conditions, the system should always be left on,
but TCS can be turned off if needed.
Notice:Do not repeatedly brake or accelerate
heavily when TCS is off. The vehicle’s driveline
could be damaged.
When TCS is switched off on AWD and STS-V vehicles,
the system may still be working. This is normal and
necessary with the hardware on the vehicle.
It may be necessary to turn the system off if the vehicle
gets stuck in sand, mud or snow and rocking the vehicle
is required. SeeRocking Your Vehicle to Get It Out on
page 4-24andIf Your Vehicle is Stuck in Sand, Mud, Ice,
or Snow on page 4-23for more information. SeeWinter
Driving on page 4-21for information on using TCS when
driving in snowy or icy conditions.
4-10

To turn the system off,
press the TCS/StabiliTrak
button located near the
shift lever.
For AWD vehicles with the Active Steering with
Enhanced StabiliTrak option, the TCS/StabiliTrak
button is used to turn traction control on and off and to
select between three stability control modes: Touring,
Competitive and Off. SeeEnhanced StabiliTrak
®
on page 4-6for instructions on selecting the proper
stability control mode.
Press and release the TCS/StabiliTrak button and TCS
will turn off and the Traction Control System Warning
Light will come on. Press the button again to turn
the system back on.
Adding non-GM accessories can affect the vehicle’s
performance. SeeAccessories and Modifications
on page 5-3for more information.
Competitive Driving Mode
The STS-V driver can select this optional handling mode
by pressing the Traction Control button, located near the
shift lever, quickly two times. STABILITY COMPETITIVE
MODE is displayed on the Driver Information Center
(DIC) when the system is working. Competitive driving
mode allows the driver to have control of the power
applied to the rear wheels, while the StabiliTrak
®system
helps steer the vehicle by selective brake application.
In competitive mode, the levels at which StabiliTrak is
engaged have been modied to better suit a performance
driving environment. When the traction control warning
light is on, the Traction Control System will not be
operating. Adjust your driving accordingly.
When the Traction Control button is pressed again,
the Traction Control System will be on. The traction
engaged symbol will be displayed briey in the DIC.
SeeDIC Warnings and Messages on page 3-79
for more information.
4-11

During some operating conditions, the active steering
might deactivate to protect the system from damage. You
might notice that the center position of the steering wheel
is changed. Unless there is a SERVICE STEERING SYS
message, the system will return to normal operation as
soon as the condition ceases, usually within a very short
period of time.
At low speeds, the active steering system requires less
movement of the steering wheel to change vehicle
direction than the normal power steering system.
Adjust your driving accordingly.
When certain steering faults are present, the active
steering deactivates and vehicle speed might be limited.
The SERVICE STEERING SYS and SPEED LIMITED
TO XXX messages will be displayed. SeeDIC Warnings
and Messages on page 3-79. The normal power steering
system is still operational. You might notice that the
center position of the steering wheel is changed and that
more steering effort at low speeds and less steering effort
at high speeds is required. You can continue to drive your
vehicle with normal power steering but you should have
your dealer/retailer inspect the steering system as soon
as possible in order to have the problem corrected and
the steering wheel position centered.
When stability control activates, the system
automatically adjusts the front road wheel steering
angle, modies the suspension stiffness, and selectivelyapplies braking pressure at any one of the vehicle’s
brakes to help maintain directional control of the vehicle.
Adjustments to the steering will not be felt in the
steering wheel. SeeEnhanced StabiliTrak
®on page 4-6.
It is recommended that the battery not be disconnected
when the steering wheel is turned from the center
position. If this occurs, the center position of the steering
wheel could be temporarily changed a small amount.
You can continue to operate your vehicle and, after
a short time, the center position of the steering wheel
will return to normal.
Steering Tips
It is important to take curves at a reasonable speed.
Traction in a curve depends on the condition of the tires
and the road surface, the angle at which the curve is
banked, and your speed. While in a curve, speed is the
one factor you can control.
If you need to reduce speed, do it before you enter the
curve, while the front wheels are straight ahead.
Try to adjust the speed so you can drive through the
curve. Maintain a reasonable, steady speed. Wait
to accelerate until you are out of the curve, and then
accelerate gently into the straightaway.
4-13

To help you steer in the direction you want to go, during
certain sharp or sudden cornering maneuvers, gear
selection is controlled. This will maximize the available
drive wheel torque and minimize the transmission
response time and shift activity. During this kind of
maneuver, the transmission shifts automatically
as vehicle speed changes.
Steering in Emergencies
There are times when steering can be more effective
than braking. For example, you come over a hill and nd
a truck stopped in your lane, or a car suddenly pulls out
from nowhere, or a child darts out from between parked
cars and stops right in front of you. You can avoid these
problems by braking — if you can stop in time. But
sometimes you cannot; there is not room. That is the
time for evasive action — steering around the problem.
Your vehicle can perform very well in emergencies like
these. First apply the brakes. SeeBraking on page 4-3.
It is better to remove as much speed as you can from a
possible collision. Then steer around the problem, to the
left or right depending on the space available.An emergency like this requires close attention and a
quick decision. If you are holding the steering wheel
at the recommended 9 and 3 o’clock positions, you can
turn it a full 180 degrees very quickly without removing
either hand. But you have to act fast, steer quickly, and
just as quickly straighten the wheel once you have
avoided the object.
The fact that such emergency situations are always
possible is a good reason to practice defensive driving
at all times and wear safety belts properly.
4-14

Off-Road Recovery
Your vehicle’s right wheels can drop off the edge of a
road onto the shoulder while driving.
If the level of the shoulder is only slightly below the
pavement, recovery should be fairly easy. Ease off the
accelerator and then, if there is nothing in the way, steer
so that your vehicle straddles the edge of the pavement.
Turn the steering wheel 3 to 5 inches, 76 to 127 mm,
(about one-eighth turn) until the right front tire contacts
the pavement edge. Then turn the steering wheel to go
straight down the roadway.
Passing
Passing another vehicle on a two-lane road can be
dangerous. To reduce the risk of danger while passing:
Look down the road, to the sides, and to crossroads
for situations that might affect a successful pass.
If in doubt, wait.
Watch for traffic signs, pavement markings, and
lines that could indicate a turn or an intersection.
Never cross a solid or double-solid line on your side
of the lane.
Do not get too close to the vehicle you want to
pass. Doing so can reduce your visibility.
Wait your turn to pass a slow vehicle.
When you are being passed, ease to the right.
Loss of Control
Let us review what driving experts say about what
happens when the three control systems — brakes,
steering, and acceleration — do not have enough friction
where the tires meet the road to do what the driver has
asked.
In any emergency, do not give up. Keep trying to steer
and constantly seek an escape route or area of less
danger.
4-15

Skidding
In a skid, a driver can lose control of the vehicle.
Defensive drivers avoid most skids by taking reasonable
care suited to existing conditions, and by not overdriving
those conditions. But skids are always possible.
The three types of skids correspond to your vehicle’s
three control systems. In the braking skid, the wheels
are not rolling. In the steering or cornering skid, too
much speed or steering in a curve causes tires to slip
and lose cornering force. And in the acceleration
skid, too much throttle causes the driving wheels
to spin.
Remember: Any traction control system helps avoid
only the acceleration skid. If your traction control system
is off, then an acceleration skid is best handled by
easing your foot off the accelerator pedal.
If your vehicle starts to slide, ease your foot off the
accelerator pedal and quickly steer the way you want
the vehicle to go. If you start steering quickly enough,
your vehicle may straighten out. Always be ready
for a second skid if it occurs.You might see the STABILITY SYS ACTIVE message
on the Driver Information Center. SeeDIC Warnings and
Messages on page 3-79andStabiliTrak®System on
page 4-6orEnhanced StabiliTrak®on page 4-6.
Of course, traction is reduced when water, snow, ice,
gravel, or other material is on the road. For safety,
you will want to slow down and adjust your driving to
these conditions. It is important to slow down on slippery
surfaces because stopping distance will be longer and
vehicle control more limited.
While driving on a surface with reduced traction, try your
best to avoid sudden steering, acceleration, or braking,
including reducing vehicle speed by shifting to a lower
gear. Any sudden changes could cause the tires to
slide. You may not realize the surface is slippery until
your vehicle is skidding. Learn to recognize warning
clues — such as enough water, ice, or packed snow on
the road to make a mirrored surface — and slow down
when you have any doubt.
Remember: Any Antilock Brake System (ABS) helps
avoid only the braking skid.
4-16

Driving in Rain and on Wet Roads
Rain and wet roads can reduce vehicle traction and
affect your ability to stop and accelerate. Always drive
slower in these types of driving conditions and avoid
driving through large puddles and deep-standing or
owing water.
{CAUTION:
Wet brakes can cause crashes. They might not
work as well in a quick stop and could cause
pulling to one side. You could lose control of
the vehicle.
After driving through a large puddle of water or a
car/vehicle wash, lightly apply the brake pedal until
the brakes work normally.
Flowing or rushing water creates strong forces.
Driving through owing water could cause your
vehicle to be carried away. If this happens, you
and other vehicle occupants could drown. Do not
ignore police warnings and be very cautious about
trying to drive through owing water.
Hydroplaning
Hydroplaning is dangerous. Water can build up under
your vehicle’s tires so they actually ride on the water.
This can happen if the road is wet enough and you are
going fast enough. When your vehicle is hydroplaning,
it has little or no contact with the road.
There is no hard and fast rule about hydroplaning.
The best advice is to slow down when the road is wet.
Other Rainy Weather Tips
Besides slowing down, other wet weather driving tips
include:
Allow extra following distance.
Pass with caution.
Keep windshield wiping equipment in good shape.
Keep the windshield washer uid reservoir lled.
Have good tires with proper tread depth. SeeTires
on page 5-54.
Turn off cruise control.
4-18

Hill and Mountain Roads
Driving on steep hills or through mountains is different
than driving on at or rolling terrain. Tips for driving
in these conditions include:
Keep the vehicle serviced and in good shape.
Check all uid levels and brakes, tires, cooling
system, and transmission.
Going down steep or long hills, shift to a
lower gear.
{CAUTION:
If you do not shift down, the brakes could get so
hot that they would not work well. You would then
have poor braking or even none going down a hill.
You could crash. Shift down to let the engine
assist the brakes on a steep downhill slope.
{CAUTION:
Coasting downhill in N (Neutral) or with the ignition
off is dangerous. The brakes will have to do all the
work of slowing down and they could get so hot
that they would not work well. You would then
have poor braking or even none going down a hill.
You could crash. Always have the engine running
and the vehicle in gear when going downhill.
Stay in your own lane. Do not swing wide or cut
across the center of the road. Drive at speeds
that let you stay in your own lane.
Top of hills: Be alert — something could be in your
lane (stalled car, accident).
Pay attention to special road signs (falling rocks
area, winding roads, long grades, passing or
no-passing zones) and take appropriate action.
4-20

Winter Driving
Driving on Snow or Ice
Drive carefully when there is snow or ice between the
tires and the road, creating less traction or grip. Wet ice
can occur at about 32°F (0°C) when freezing rain
begins to fall, resulting in even less traction. Avoid
driving on wet ice or in freezing rain until roads can be
treated with salt or sand.
Drive with caution, whatever the condition. Accelerate
gently so traction is not lost. Accelerating too quickly
causes the wheels to spin and makes the surface under
the tires slick, so there is even less traction.
Try not to break the fragile traction. If you accelerate too
fast, the drive wheels will spin and polish the surface
under the tires even more.TheTraction Control System (TCS) on page 4-10
improves the ability to accelerate on slippery roads,
but slow down and adjust your driving to the road
conditions. When driving through deep snow, turn off
the traction control system to help maintain vehicle
motion at lower speeds.
TheAntilock Brake System (ABS) on page 4-4improves
vehicle stability during hard stops on a slippery roads,
but apply the brakes sooner than when on dry
pavement.
Allow greater following distance on any slippery road
and watch for slippery spots. Icy patches can occur on
otherwise clear roads in shaded areas. The surface
of a curve or an overpass can remain icy when the
surrounding roads are clear. Avoid sudden steering
maneuvers and braking while on ice.
Turn off cruise control, if equipped, on slippery surfaces.
4-21