brake light CHEVROLET IMPALA 2009 9.G User Guide

SERVICE BRAKE SYSTEM
This message displays when service is required on
the brake system. Have the brake system serviced by
your dealer/retailer as soon as possible. The brake
system warning light also appears on the instrument
panel cluster when this message appears on the DIC.
SeeBrake System Warning Light on page 3-30.
SERVICE POWER STEERING
This message displays when a problem is detected
with the power steering system. When this message is
displayed, you may notice that the effort required to steer
the vehicle increases or feels heavier, but you will still be
able to steer the vehicle. Have your vehicle serviced by
your dealer/retailer immediately.
SERVICE STABILITRAK
If your vehicle has Electronic Stability Control (ESC),
this message displays if there has been a problem
detected with ESC. The ESC/TCS light also appears
on the instrument panel cluster. SeeElectronic Stability
Control (ESC) on page 4-6for more information.
If this message turns on while you are driving, pull
off the road as soon as possible and stop carefully.Try resetting the system by turning the ignition off and
then back on. If this message still stays on or turns back
on again while you are driving, your vehicle
needs service. Have the system inspected by your
dealer/retailer as soon as possible.
SERVICE THEFT SYSTEM
This message displays when there is a problem with
the theft-deterrent system programmed in the key. A fault
has been detected in the system which means that the
system is disabled and it is not protecting the vehicle.
The vehicle usually restarts; however, you may want to
take the vehicle to your dealer/retailer before turning off
the engine. SeePASS-Key
®III+ Electronic Immobilizer
Operation on page 2-18for more information.
SERVICE TIRE MONITOR SYSTEM
On vehicles with the Tire Pressure Monitor
System (TPMS), this message displays if a part on
the TPMS is not working properly. The tire pressure
light also ashes and then remains on during the same
ignition cycle. SeeTire Pressure Light on page 3-35.
Several conditions may cause this message to appear.
SeeTire Pressure Monitor Operation on page 5-63
for more information. If the warning comes on and stays
on, there may be a problem with the TPMS. See your
dealer/retailer.
3-54

Braking
SeeBrake System Warning Light on page 3-30.
Braking action involves perception time and reaction
time. Deciding to push the brake pedal is perception
time. Actually doing it is reaction time.
Average reaction time is about three-fourths of a
second. But that is only an average. It might be less
with one driver and as long as two or three seconds or
more with another. Age, physical condition, alertness,
coordination, and eyesight all play a part. So do alcohol,
drugs, and frustration. But even in three-fourths of a
second, a vehicle moving at 60 mph (100 km/h) travels
66 feet (20 m). That could be a lot of distance in an
emergency, so keeping enough space between
the vehicle and others is important.
And, of course, actual stopping distances vary greatly
with the surface of the road, whether it is pavement
or gravel; the condition of the road, whether it is
wet, dry, or icy; tire tread; the condition of the brakes;
the weight of the vehicle; and the amount of brake force
applied.Avoid needless heavy braking. Some people drive
in spurts — heavy acceleration followed by heavy
braking — rather than keeping pace with traffic. This is a
mistake. The brakes might not have time to cool between
hard stops. The brakes will wear out much faster with a
lot of heavy braking. Keeping pace with the traffic and
allowing realistic following distances eliminates a lot of
unnecessary braking. That means better braking and
longer brake life.
If the engine ever stops while the vehicle is being driven,
brake normally but do not pump the brakes. If the brakes
are pumped, the pedal could get harder to push down. If
the engine stops, there will still be some power brake
assist but it will be used when the brake is applied. Once
the power assist is used up, it can take longer to stop and
the brake pedal will be harder to push.
Adding non-dealer/non-retailer accessories can affect
vehicle performance. SeeAccessories and Modifications
on page 5-3.
4-4

Antilock Brake System (ABS)
The vehicle might have the Antilock Brake System
(ABS), an advanced electronic braking system that helps
prevent a braking skid.
If the vehicle has ABS,
this warning light on the
instrument panel cluster
comes on briey when the
vehicle is started.
When the engine is started, or when the vehicle begins
to drive away, ABS checks itself. A momentary motor
or clicking noise might be heard while this test is going
on, and it might even be noticed that the brake pedal
moves or pulses a little. This is normal.
Let us say the road is wet and you are driving safely.
Suddenly, an animal jumps out in front of you. You slam
on the brakes and continue braking. Here is what
happens with ABS:
A computer senses that the wheels are slowing down. If
one of the wheels is about to stop rolling, the computer
will separately work the brakes at each front wheel
and at both rear wheels.ABS can change the brake pressure to each wheel, as
required, faster than any driver could. This can help
the driver steer around the obstacle while braking hard.
As the brakes are applied, the computer keeps
receiving updates on wheel speed and controls braking
pressure accordingly.
Remember: ABS does not change the time needed to get
a foot up to the brake pedal or always decrease stopping
distance. If you get too close to the vehicle in front of you,
there will not be enough time to apply the brakes if that
vehicle suddenly slows or stops. Always leave enough
room up ahead to stop, even with ABS.
Using ABS
Do not pump the brakes. Just hold the brake pedal
down rmly and let antilock work. A slight brake pedal
pulsation might be felt or some noise might be
heard, but this is normal.
4-5

Braking in Emergencies
At some time, nearly every driver gets into a situation
that requires hard braking.
If the vehicle has ABS, it allows the driver to steer and
brake at the same time. However, if the vehicle does
not have ABS, the rst reaction — to hit the brake pedal
hard and hold it down — might be the wrong thing to
do. The wheels can stop rolling. Once they do, the
vehicle cannot respond to the driver’s steering.
Momentum will carry it in whatever direction it was
headed when the wheels stopped rolling. That could be
off the road, into the very thing the driver was trying
to avoid, or into traffic.
If the vehicle does not have ABS, use a “squeeze”
braking technique. This gives maximum braking while
maintaining steering control. Do this by pushing on
the brake pedal with steadily increasing pressure.
In an emergency, you will probably want to squeeze the
brakes hard without locking the wheels. If you hear or
feel the wheels sliding, ease off the brake pedal.
This helps retain steering control. With ABS, it is
different. SeeAntilock Brake System (ABS) on page 4-5.
In many emergencies, steering can help more than
even the very best braking.
Electronic Stability Control (ESC)
Your vehicle may have an Electronic Stability Control
(ESC) system which combines antilock brake, traction
and stability control systems and helps the driver
maintain directional control of the vehicle in most driving
conditions.
When you rst start your vehicle and begin to drive
away, the system performs several diagnostic checks to
ensure there are no problems. You may hear or feel
the system working. This is normal and does not mean
there is a problem with your vehicle. The system
should initialize before the vehicle reaches 20 mph
(32 km/h).
If the system fails to turn on or activate, the ESC/TCS
light will be on solid, and the SERVICE STABILITRAK
message will be displayed.
For more information, seeDriver Information Center
(DIC) on page 3-42.
4-6

If the problem does not clear after restarting the vehicle,
you should see your dealer/retailer for service. See
DIC Warnings and Messages on page 3-49for more
information.
Adding non-dealer/non-retailer accessories can affect
your vehicle’s performance. SeeAccessories and
Modifications on page 5-3for more information.
Traction Control System (TCS)
The vehicle may have a Traction Control System (TCS)
that limits wheel spin. This is especially useful in slippery
road conditions. The system operates only if it senses
that one or both of the front wheels are spinning or
beginning to lose traction. When this happens, the
system reduces engine power and may also upshift
the transmission and apply the front brakes to limit
wheel spin.
This light will ash
when the TCS is limiting
wheel spin.
The system may be heard or felt while it is working, but
this is normal.If cruise control is being used when TCS begins to limit
wheel spin, the cruise control will automatically
disengage. Cruise control may be reengaged when road
conditions allow. SeeCruise Control on page 3-9.
The TCS operates in all transmission shift lever
positions. But the system can upshift the transmission
only as high as the shift lever position chosen, so
use the lower gears only when necessary. See
Automatic Transmission Operation on page 2-24.
When the system is on,
this warning light comes
on and stays on if there is
a problem.
A SERVICE TRACTION CONTROL message also
appears on the DIC. When this warning light is on, the
system will not limit wheel spin. Adjust your driving
accordingly. SeeDIC Warnings and Messages
on page 3-49for more information.
To limit wheel spin, especially in slippery road
conditions, TCS should always be left on. But the
system can be turned off if needed.
4-8

Off-Road Recovery
The 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 the vehicle straddles the edge of the
pavement. Turn the steering wheel 3 to 5 inches, 8 to
13 cm, (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.
4-11

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 5-53.
Turn off cruise control.
4-14

Brakes
Brake Fluid
The brake master cylinder
reservoir is lled with
DOT 3 brake uid. See
Engine Compartment
Overview on page 5-14
for the location of the
reservoir.
There are only two reasons why the brake uid level in
the reservoir might go down:
The brake uid level goes down because of normal
brake lining wear. When new linings are installed,
the uid level goes back up.
A uid leak in the brake hydraulic system can also
cause a low uid level. Have the brake hydraulic
system xed, since a leak means that sooner
or later the brakes will not work well.Do not top off the brake uid. Adding uid does not
correct a leak. If uid is added when the linings
are worn, there will be too much uid when new brake
linings are installed. Add or remove brake uid, as
necessary, only when work is done on the brake
hydraulic system.
{CAUTION:
If too much brake uid is added, it can spill on the
engine and burn, if the engine is hot enough. You
or others could be burned, and the vehicle could
be damaged. Add brake uid only when work is
done on the brake hydraulic system.
When the brake uid falls to a low level, the brake
warning light comes on. SeeBrake System Warning
Light on page 3-30.
5-37

Brake Wear
This vehicle has disc brakes. Disc brake pads have
built-in wear indicators that make a high-pitched warning
sound when the brake pads are worn and new pads
are needed. The sound can come and go or be heard all
the time the vehicle is moving, except when applying
the brake pedal rmly.
{CAUTION:
The brake wear warning sound means that soon
the brakes will not work well. That could lead to an
accident. When the brake wear warning sound is
heard, have the vehicle serviced.
Notice:Continuing to drive with worn-out brake
pads could result in costly brake repair.Some driving conditions or climates can cause a brake
squeal when the brakes are rst applied or lightly
applied. This does not mean something is wrong with
the brakes.
Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts
in the proper sequence to torque specications
inCapacities and Specifications on page 5-101.
Brake linings should always be replaced as complete
axle sets.Brake Pedal Travel
See your dealer/retailer if the brake pedal does not
return to normal height, or if there is a rapid increase in
pedal travel. This could be a sign that brake service
might be required.
Brake Adjustment
Every time the brakes are applied, with or without the
vehicle moving, the brakes adjust for wear.
5-39

Different Size Tires and Wheels
If you add wheels or tires that are a different size than
your original equipment wheels and tires, this may affect
the way your vehicle performs, including its braking, ride
and handling characteristics, stability, and resistance
to rollover. Additionally, if your vehicle has electronic
systems such as, antilock brakes, traction control, and
electronic stability control, the performance of these
systems can be affected.
{CAUTION:
If you add different sized wheels, your vehicle may
not provide an acceptable level of performance and
safety if tires not recommended for those wheels
are selected. You may increase the chance that you
will crash and suffer serious injury. Only use GM
specic wheel and tire systems developed for your
vehicle, and have them properly installed by a GM
certied technician.
SeeBuying New Tires on page 5-69andAccessories
and Modifications on page 5-3for additional information.
Uniform Tire Quality Grading
Quality grades can be found where applicable on
the tire sidewall between tread shoulder and
maximum section width. For example:
Treadwear 200 Traction AA
Temperature A
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration (NHTSA), which
grades tires by treadwear, traction, and
temperature performance. This applies only to
vehicles sold in the United States. The grades are
molded on the sidewalls of most passenger car
tires. The Uniform Tire Quality Grading (UTQG)
system does not apply to deep tread, winter-type
snow tires, space-saver, or temporary use spare
tires, tires with nominal rim diameters of
10 to 12 inches (25 to 30 cm), or to some
limited-production tires.
While the tires available on General Motors
passenger cars and light trucks may vary with
respect to these grades, they must also conform
to federal safety requirements and additional
General Motors Tire Performance Criteria (TPC)
standards.
5-71