service CHEVROLET IMPALA 2007 9.G Repair Manual

Brake Wear
Your vehicle has four-wheel 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 your vehicle is moving, except when
you are pushing on 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 you hear
the brake wear warning sound, have your
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 Specications on
page 403.
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 you apply the brakes, with or without
the vehicle moving, the brakes adjust for wear.
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9. Connect the other end of the negative (−) cable
at least 18 inches (45 cm) away from the dead
battery, but not near engine parts that move.
The electrical connection is just as good there,
and the chance of sparks getting back to the
battery is much less.
10. Now start the vehicle with the good battery
and run the engine for a while.
11. Try to start the vehicle that had the dead
battery. If it will not start after a few tries,
it probably needs service.
Notice:If the jumper cables are connected
or removed in the wrong order, electrical
shorting may occur and damage the vehicle.
The repairs would not be covered by your
warranty. Always connect and remove
the jumper cables in the correct order, making
sure that the cables do not touch each other
or other metal.A. Heavy, Unpainted Metal Engine Part or
Remote Negative (−) Terminal
B. Good Battery or Remote Positive (+) Terminal
and Remote Negative (−) Terminals
C. Dead Battery or Remote Positive (+) Terminal
Jumper Cable Removal
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To disconnect the jumper cables from both
vehicles, do the following:
1. Disconnect the black negative (−) cable from
the vehicle that had the dead battery.
2. Disconnect the black negative (−) cable from
the vehicle with the good battery.
3. Disconnect the red positive (+) cable from the
vehicle with the good battery.
4. Disconnect the red positive (+) cable from the
other vehicle.
5. Return the fuse block cover to its original
position.Headlamp Aiming
Headlamp aim has been preset at the factory and
should need no further adjustment.
However, if your vehicle is damaged in an accident,
the headlamp aim may be affected. Aim adjustment
to the low-beam headlamps may be necessary if it
is difficult to see the lane markers (for horizontal
aim), or if oncoming drivers ash their high-beam
headlamps at you (for vertical aim).
If you believe your headlamps need to be
re-aimed, it is recommend that you take the vehicle
to your dealer for service.
Bulb Replacement
For the proper type of replacement bulbs,
seeReplacement Bulbs on page 349.
For any bulb changing procedure not listed in this
section, contact your dealer.
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Tires
Your new vehicle comes with high-quality tires
made by a leading tire manufacturer. If you ever
have questions about your tire warranty and where
to obtain service, see your GM Warranty booklet
for details. For additional information refer to
the tire manufacturer’s booklet included with
your vehicle.
{CAUTION:
Poorly maintained and improperly used
tires are dangerous.
Overloading your vehicle’s tires can
cause overheating as a result of too
much friction. You could have an
air-out and a serious accident. See
Loading Your Vehicle on page 277.
CAUTION: (Continued)
CAUTION: (Continued)

Underinated tires pose the same
danger as overloaded tires. The
resulting accident could cause serious
injury. Check all tires frequently to
maintain the recommended pressure.
Tire pressure should be checked when
your vehicle’s tires are cold. See
Inflation - Tire Pressure on page 359.
Overinated tires are more likely to be
cut, punctured, or broken by a sudden
impact — such as when you hit a
pothole. Keep tires at the
recommended pressure.
Worn, old tires can cause accidents.
If the tire’s tread is badly worn, or if
your vehicle’s tires have been
damaged, replace them.
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Tire Sidewall Labeling
Useful information about a tire is molded into its
sidewall. The examples below show a typical
passenger vehicle tire and a compact spare tire
sidewall.(A) Tire Size:The tire size is a combination of
letters and numbers used to dene a particular
tire’s width, height, aspect ratio, construction type,
and service description. See the “Tire Size”
illustration later in this section for more detail.
(B) TPC Spec (Tire Performance Criteria
Specication):Original equipment tires designed
to GM’s specic tire performance criteria have
a TPC specication code molded onto the sidewall.
GM’s TPC specications meet or exceed all
federal safety guidelines.
(C) DOT (Department of Transportation):
The Department of Transportation (DOT) code
indicates that the tire is in compliance with the U.S.
Department of Transportation Motor Vehicle
Safety Standards.
Passenger (P-Metric) Tire Example
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(B) Tire Ply Material:The type of cord and
number of plies in the sidewall and under the
tread.
(C) Tire Identication Number (TIN):The letters
and numbers following the DOT (Department of
Transportation) code is the Tire Identication
Number (TIN). The TIN shows the manufacturer
and plant code, tire size, and date the tire
was manufactured. The TIN is molded onto both
sides of the tire, although only one side may have
the date of manufacture.
(D) Maximum Cold Ination Load Limit:
Maximum load that can be carried and the
maximum pressure needed to support that load.(E) Tire Ination:The temporary use tire or
compact spare tire should be inated to 60 psi
(420 kPa). For more information on tire pressure
and ination seeInation - Tire Pressure on
page 359.
(F) Tire Size:A combination of letters and
numbers dene a tire’s width, height, aspect ratio,
construction type, and service description. The
letter T as the rst character in the tire size means
the tire is for temporary use only.
(G) TPC Spec (Tire Performance Criteria
Specication):Original equipment tires designed
to GM’s specic tire performance criteria have
a TPC specication code molded onto the sidewall.
GM’s TPC specications meet or exceed all
federal safety guidelines.
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Tire Size
The following illustration shows an example of a
typical passenger vehicle tire size.
(A) Passenger (P-Metric) Tire:The United
States version of a metric tire sizing system.
The letter P as the rst character in the tire size
means a passenger vehicle tire engineered
to standards set by the U.S. Tire and Rim
Association.
(B) Tire Width:The three-digit number indicates
the tire section width in millimeters from sidewall
to sidewall.(C) Aspect Ratio:A two-digit number that
indicates the tire height-to-width measurements.
For example, if the tire size aspect ratio is 60, as
shown in item C of the illustration, it would mean
that the tire’s sidewall is 60 percent as high as
it is wide.
(D) Construction Code:A letter code is used to
indicate the type of ply construction in the tire. The
letter R means radial ply construction; the letter D
means diagonal or bias ply construction; and the
letter B means belted-bias ply construction.
(E) Rim Diameter:Diameter of the wheel
in inches.
(F) Service Description:These characters
represent the load range and speed rating of the
tire. The load index represents the load carry
capacity a tire is certied to carry. The load index
can range from 1 to 279. The speed rating is
the maximum speed a tire is certied to carry a
load. Speed ratings range from A to Z.
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Your vehicle has also been equipped with a TPMS
malfunction indicator to indicate when the system is
not operating properly. The TPMS malfunction
indicator is combined with the low tire pressure
telltale. When the system detects a malfunction,
the telltale will ash for approximately one minute
and then remain continuously illuminated. This
sequence will continue upon subsequent vehicle
start-ups as long as the malfunction exists.
When the malfunction indicator is illuminated, the
system may not be able to detect or signal low
tire pressure as intended. TPMS malfunctions may
occur for a variety of reasons, including the
installation of replacement or alternate tires or
wheels on the vehicle that prevent the TPMS from
functioning properly. Always check the TPMS
malfunction telltale after replacing one or more
tires or wheels on your vehicle to ensure that the
replacement or alternate tires and wheels allow
the TPMS to continue to function properly.
A Tire and Loading Information label, attached to
your vehicle, shows the size of your vehicle’s
original equipment tires and the correct ination
pressure for your vehicle’s tires when theyare cold. SeeLoading Your Vehicle on page 277,
for an example of the Tire and Loading
Information label and its location on your vehicle.
Also seeInation - Tire Pressure on page 359.
Your vehicle’s TPMS system can warn you about
a low tire pressure condition but it does not
replace normal tire maintenance. SeeTire
Inspection and Rotation on page 364andTires on
page 351.
Notice:Do not use a tire sealant if your vehicle
has Tire Pressure Monitors. The liquid sealant
can damage the tire pressure monitor sensors.
The TPMS will not function properly if one or more
of the TPMS sensors are missing or inoperable.
If the system detects a missing or inoperable
sensor, an error message SERVICE TIRE
MONITOR SYSTEM will be shown on the DIC
display. If you have replaced a tire/wheel assembly
without transferring the TPMS sensors, the error
message will be displayed. Once you re-install the
TPMS sensors, the error message should go
off. See your GM dealer for service if all TPMS
sensors are installed and the error message
comes on and stays on.
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TPMS Sensor Identication Codes
Each TPMS sensor has a unique identication
code. Any time you replace one or more of
the TPMS sensors or rotate the vehicle’s tires,
the identication codes will need to be matched
to the new tire/wheel position. The sensors
are matched, to the tire/wheel positions, in the
following order: driver’s side front tire, passenger’s
side front tire, passenger’s side rear tire, and
driver’s side rear tire using a TPMS diagnostic
tool. See your GM dealer for service.
The TPMS sensors may also be matched to each
tire/wheel position by increasing or decreasing
the tire’s air pressure. When increasing the tire’s
pressure, do not exceed the maximum ination
pressure indicated on the tire’s sidewall.
You will have two minutes to match each tire
and wheel position. If it takes longer than
two minutes to match any tire and wheel position,
the matching process stops and you will need
to start over.The TPMS matching process is outlined below:
1. Set the parking brake.
2. Turn the ignition switch to RUN with the
engine off.
3. Using the DIC, press the vehicle information
button until the LEARN TIRE POSITIONS
message displays.
4. Press the set/reset button to allow the system
to learn the tire positions. The horn will sound
twice to indicate the receiver is ready, and
the TIRE LEARNING ACTIVE message
will display. The TPMS system is ready for
the sensor matching process to begin.
5. Start with the driver’s side front tire.
6. Remove the valve cap from the tire’s valve
stem. Activate the TPMS sensor by increasing
or decreasing the tire’s air pressure for
ve seconds, or until a horn chirp sounds.
The horn chirp, which may take up to
30 seconds to sound, conrms that the sensor
identication code has been matched to the
tire/wheel position. To decrease the tire’s
air-pressure use the pointed end of the valve
cap, a pencil-style air pressure gage, or a key.
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7. Proceed to the passenger’s side front tire, and
repeat the procedure in Step 6.
8. Proceed to the passenger’s side rear tire, and
repeat the procedure in Step 6.
9. Proceed to the driver’s side rear tire, and
repeat the procedure in Step 6.
10. After hearing the conrming horn chirp for the
driver’s side rear tire, the tire learning process
ends. Turn the ignition switch to OFF.
11. Set all four tires to the recommended air
pressure level as indicated on the Tire
and Loading Information label.
12. Put the valve caps back on the valve stems.
Federal Communications Commission
(FCC) and Industry and Science Canada
The Tire Pressure Monitor System (TPMS)
operates on a radio frequency and complies with
Part 15 of the FCC Rules. Operation is subject
to the following two conditions:
1. This device may not cause harmful
interference.
2. This device must accept any interference
received, including interference that may
cause undesired operation.The Tire Pressure Monitor System (TPMS)
operates on a radio frequency and complies with
RSS-210 of Industry and Science Canada.
Operation is subject to the following two conditions:
1. This device may not cause interference.
2. This device must accept any interference
received, including interference that may
cause undesired operation of the device.
Changes or modications to this system by other
than an authorized service facility could void
authorization to use this equipment.
Tire Inspection and Rotation
Tires should be rotated every 5,000 to 8,000 miles
(8 000 to 13 000 km).
Any time you notice unusual wear, rotate your tires
as soon as possible and check wheel alignment.
Also check for damaged tires or wheels. SeeWhen
It Is Time for New Tires on page 366andWheel
Replacement on page 371for more information.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The
rst rotation is the most important. SeeScheduled
Maintenance on page 408for scheduled rotation
intervals.
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