brakes GMC SIERRA 2007 User Guide

CHECK TIRE PRESSURE
If your vehicle has a Tire Pressure Monitor (TPM)
system, this message displays when the
pressure in one or more of the vehicle’s tires need
to be checked. This message also displays
LEFT FRONT, RIGHT FRONT, LEFT REAR, or
RIGHT REAR to indicate which tire needs to
be checked. You can receive more than one tire
pressure message at a time. To read the other
messages that may have been sent at the same
time, press the set/reset button or the trip
odometer reset stem. If a tire pressure message
appears on the DIC, stop as soon as you can.
Have the tire pressures checked and set to those
shown on the Tire Loading Information label.
SeeTires on page 550,Loading Your Vehicle on
page 425, andInation - Tire Pressure on
page 559. The DIC display also shows the tire
pressure values for the front and rear tires
by pressing the vehicle information button. See
“DIC Operation and Displays (With DIC Buttons)”
earlier in this section. If the tire pressure is
low, the low tire pressure warning light comes on.
SeeTire Pressure Light on page 259.
CHECK TRAILER WIRING
On vehicles with the Integrated Trailer Brake
Control (ITBC) system, this message may display
and a chime may sound when one of the
following conditions exists:
A trailer with electric brakes becomes
disconnected from the vehicle.
If the disconnect occurs while the vehicle
is stopped, this message clears itself
after a short time.
If the disconnect occurs while the vehicle
is moving, this message stays on until
the ignition is turned off.
There is a short in the wiring to the electric
trailer brakes.
When this message displays, power is no longer
available to the trailer brakes.
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SERVICE 4 WHEEL DRIVE
This message displays if a problem occurs with
the four-wheel-drive system. If this message
appears, stop as soon as possible and turn off the
vehicle. Restart the vehicle and check for the
message on the DIC display. If the message is still
displayed or appears again when you begin
driving, the four-wheel-drive system needs service.
See your dealer.
SERVICE AIR BAG
This message displays if there is a problem with
the airbag system. Have your dealer inspect
the system for problems. SeeAirbag Readiness
Light on page 250andAirbag System on page 83
for more information.
SERVICE BATTERY CHARGING
SYSTEM
On some vehicles, this message displays if there
is a problem with the battery charging system.
Under certain conditions, the charging system light
may also turn on in the instrument panel cluster.
SeeCharging System Light on page 254.
Driving with this problem could drain the battery.Turn off all unnecessary accessories. Have the
electrical system checked as soon as possible.
See your dealer.
SERVICE BRAKE SYSTEM
This message displays along with the brake
system warning light if there is a problem with the
brake system. SeeBrake System Warning
Light on page 256. If this message appears, stop
as soon as possible and turn off the vehicle.
Restart the vehicle and check for the message on
the DIC display. If the message is still displayed
or appears again when you begin driving, the
brake system needs service as soon as possible.
See your dealer.
SERVICE BRAKES SOON
This message displays if there is a problem with
the brake system. If this message appears, stop as
soon as possible and turn off the vehicle. Restart
the vehicle and check for the message on the
DIC display. If the message is still displayed
or appears again when you begin driving, the
brake system needs service. See your dealer.
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SERVICE TRAILER BRAKE SYSTEM
On vehicles with the Integrated Trailer Brake
Control (ITBC) system, this message displays and
a chime sounds when there is a problem with
the ITBC system.
When this message displays, power is no longer
available to the trailer brakes.
As soon as it is safe to do so, carefully pull your
vehicle over to the side of the road and turn
the ignition off. Check the wiring connection to the
trailer and turn the ignition back on. If this
message still displays, either your vehicle or the
trailer needs service. See your dealer.
See “Integrated Trailer Brake Control System”
underTowing a Trailer on page 445for more
information.
STABILITRAK OFF
If your vehicle has StabiliTrak®, this message
displays when you turn off StabiliTrak®, or when
the stability control has been automatically
disabled. To limit wheel spin and realize the full
benets of the stability enhancement system, you
should normally leave StabiliTrak
®on. However,
you should turn StabiliTrak®off if your vehicle gets
stuck in sand, mud, ice, or snow and you wantto rock your vehicle to attempt to free it, or if you
are driving in extreme off-road conditions and
require more wheel spin. SeeIf Your Vehicle is
Stuck in Sand, Mud, Ice, or Snow on page 422.To
turn the StabiliTrak
®system on or off, see
StabiliTrak®System on page 381.
There are several conditions that can cause this
message to appear.
One condition is overheating, which could
occur if StabiliTrak®activates continuously
for an extended period of time.
The message also displays if the brake
system warning light is on. SeeBrake System
Warning Light on page 256.
The message could display if the stability
system takes longer than usual to complete its
diagnostic checks due to driving conditions.
The message displays if an engine or vehicle
related problem has been detected and the
vehicle needs service. See your dealer.
The message also displays if the vehicle is
shifted into 4LO.
The message turns off as soon as the conditions
that caused the message to be displayed are
no longer present.
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TIGHTEN GAS CAP
This message may display along with the check
engine light on the instrument panel cluster if
the vehicle’s fuel cap is not tightened properly. See
Malfunction Indicator Lamp on page 260.
Reinstall the fuel cap fully. SeeFilling the Tank on
page 493. The diagnostic system can determine
if the fuel cap has been left off or improperly
installed. A loose or missing fuel cap allows fuel to
evaporate into the atmosphere. A few driving
trips with the cap properly installed should turn this
light and message off.
TIRE LEARNING ACTIVE
If your vehicle has a Tire Pressure Monitor (TPM)
system, this message displays when the system
is re-learning the tire positions on your vehicle.
SeeDIC Operation and Displays (With DIC
Buttons) on page 268orDIC Operation and
Displays (Without DIC Buttons) on page 275for
more information. The tire positions must be
re-learned after rotating the tires or after replacing
a tire or sensor. SeeTire Inspection and
Rotation on page 565,Tire Pressure Monitor
System on page 561, andInation - Tire Pressure
on page 559for more information.
TRACTION CONTROL OFF
If your vehicle has StabiliTrak®, this message
displays when the Traction Control System (TCS)
is turned off. Adjust your driving accordingly.
SeeStabiliTrak
®System on page 381for more
information.
TRAILER CONNECTED
On vehicles with the Integrated Trailer Brake
Control (ITBC) system, this message displays
briey when a trailer with electric brakes is
rst connected to the vehicle.
This message clears itself after several seconds.
This message also clears if you acknowledge
it. After this message clears, the TRAILER
GAIN/OUTPUT display appears in the DIC.
See “TRAILER GAIN/OUTPUT” underDIC
Operation and Displays (With DIC Buttons) on
page 268orDIC Operation and Displays (Without
DIC Buttons) on page 275and “Integrated
Trailer Brake Control System” underTowing a
Trailer on page 445for more information.
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Control of a Vehicle
You have three systems that make your vehicle
go where you want it to go. They are the brakes,
the steering, and the accelerator. All three
systems have to do their work at the places where
the tires meet the road.
Sometimes, as when you are driving on snow or
ice, it is easy to ask more of those control systems
than the tires and road can provide. That means
you can lose control of your vehicle. See
StabiliTrak
®System on page 381.
Adding non-GM accessories can affect your
vehicle’s performance. SeeAccessories and
Modications on page 486.
Braking
SeeBrake System Warning Light on page 256.
Braking action involves perception time and
reaction time.
First, you have to decide to push on the brake
pedal. That is perception time. Then you have to
bring up your foot and do it. That 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 your 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 may not have time to
cool between hard stops. The brakes will wear out
much faster if you do a lot of heavy braking. If you
keep pace with the traffic and allow realistic
following distances, you will eliminate a lot of
unnecessary braking. That means better braking
and longer brake life.
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If your vehicle’s engine ever stops while you are
driving, brake normally but do not pump the
brakes. If you do, the pedal may get harder to
push down. If the engine stops, you will still have
some power brake assist. But you will use it
when you brake. Once the power assist is used
up, it may take longer to stop and the brake pedal
will be harder to push.
Adding non-GM accessories can affect your
vehicle’s performance. SeeAccessories and
Modications on page 486.
Anti-Lock Brake System (ABS)
Your vehicle has the Anti-Lock Brake System
(ABS), an advanced electronic braking system that
will help prevent a braking skid.
When you start your engine and begin to drive
away, ABS will check itself. You may hear a
momentary motor or clicking noise while this test
is going on. This is normal.If there is a problem
with ABS, this warning
light will stay on.
SeeAnti-Lock Brake
System Warning
Light on page 257.
Along with ABS, your vehicle has a Dynamic Rear
Proportioning (DRP) system. If there is a DRP
problem, both the brake and ABS warning lights
will come on accompanied by a 10-second
chime. The lights and chime will come on each
time the ignition is turned on until the problem is
repaired. See your dealer for service.
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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 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 faster than
any driver could. The computer is programmed to
make the most of available tire and road
conditions. This can help you steer around the
obstacle while braking hard.
As you brake, your computer keeps receiving
updates on wheel speed and controls braking
pressure accordingly.
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Remember: ABS does not change the time you
need to get your foot up to the brake pedal
or always decrease stopping distance. If you get
too close to the vehicle in front of you, you will not
have time to apply your brakes if that vehicle
suddenly slows or stops. Always leave enough
room up ahead to stop, even though you
have ABS.
Using ABS
Do not pump the brakes. Just hold the brake
pedal down rmly and let anti-lock work for you.
You may feel the brakes vibrate, or you may notice
some noise, but this is normal.
Braking in Emergencies
With ABS, you can steer and brake at the same
time. In many emergencies, steering can help you
more than even the very best braking.
Locking Rear Axle
If your vehicle has this feature, your locking rear
axle can give you additional traction on snow, mud,
ice, sand or gravel. It works like a standard axle
most of the time, but when one of the rear wheels
has no traction and the other does, this feature will
allow the wheel with traction to move the vehicle.
StabiliTrak®System
Your vehicle may be equipped with the
StabiliTrak®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). In
some cases, it may take approximately two
miles of driving before the system initializes.
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Traction Control Operation
The traction control system is part of the
StabiliTrak®system. Traction control limits wheel
spin by reducing engine power to the wheels
(engine speed management) and by applying
brakes to each individual wheel (brake-traction
control) as necessary.
The traction control system is enabled
automatically when you start your vehicle. It will
activate and the StabiliTrak
®light will ash if
it senses that any of the wheels are spinning or
beginning to lose traction while driving. If you turn
off traction control, only the brake-traction
control portion of traction control will work. The
engine speed management will be disabled. In this
mode, engine power is not reduced automatically
and the driven wheels can spin more freely.
This can cause the brake-traction control to
activate constantly.Notice:If you allow the wheel(s) of one axle
to spin excessively while the StabiliTrak
®, ABS
and brake warning lights and the SERVICE
STABILITRAK message are displayed,
you could damage the transfer case. The
repairs would not be covered by your warranty.
Reduce engine power and do not spin the
wheel(s) excessively while these lights and this
message are displayed.
The traction control system may activate on dry or
rough roads or under conditions such as heavy
acceleration while turning or abrupt
upshifts/downshifts of the transmission. When this
happens, you may notice a reduction in
acceleration, or may hear a noise or vibration.
This is normal.
If your vehicle is in cruise control when the system
activates, the StabiliTrak
®light will ash and the
cruise control will automatically disengage.
When road conditions allow you to use cruise
again, you may re-engage the cruise control. See
Cruise Control on page 218.
StabiliTrak
®may also turn off automatically if it
determines that a problem exists with the system. If
the problem does not clear itself after restarting the
vehicle, you should see your dealer for service.
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Adding non-GM accessories can affect your
vehicle’s performance. SeeAccessories and
Modications on page 486.
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 378. 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.
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