brake CADILLAC CTS 2008 2.G Workshop Manual

Service
For service and parts needs, visit your dealer/retailer.
You will receive genuine GM parts and GM-trained and
supported service people.
Genuine GM parts have one of these marks:
Accessories and Modications
When non-dealer/non-retailer accessories are added to
your vehicle they can affect your vehicle’s performance
and safety, including such things as, airbags, braking,
stability, ride and handling, emissions systems,
aerodynamics, durability, and electronic systems like
antilock brakes, traction control and stability control.
Some of these accessories could even cause
malfunction or damage not covered by warranty.
GM Accessories are designed to complement and
function with other systems on your vehicle. Your GM
dealer/retailer can accessorize your vehicle using
genuine GM Accessories. When you go to your GM
dealer/retailer and ask for GM Accessories, you
will know that GM-trained and supported service
technicians will perform the work using genuine
GM Accessories.
Also, seeAdding Equipment to Your Airbag-Equipped
Vehicle on page 1-70.
5-4

Checking Things Under
the Hood
{CAUTION:
An electric fan under the hood can start up
and injure you even when the engine is not
running. Keep hands, clothing, and tools away
from any underhood electric fan.
{CAUTION:
Things that burn can get on hot engine parts
and start a re. These include liquids like fuel,
oil, coolant, brake uid, windshield washer and
other uids, and plastic or rubber. You or
others could be burned. Be careful not to drop
or spill things that will burn onto a hot engine.
Hood Release
To open the hood, do the following:
1. Pull the hood release
lever with this symbol
on it. It is located inside
the vehicle on the lower
left side of the
instrument panel.
5-12

A. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-40.
B. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-123.
C. Remote Positive (+) Terminal. SeeJump Starting on
page 5-45.
D. Remote Negative (+) Terminal. SeeJump Starting
on page 5-45.
E. Passenger Compartment Air Filter. SeePassenger
Compartment Air Filter on page 3-29.
F. Engine Cooling Fan. SeeCooling System on
page 5-34.
G. Power Steering Fluid Reservoir (Under Engine
Cover). SeePower Steering Fluid on page 5-39.H. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-16.
I. Engine Oil Dipstick (Out of View). See “Checking
Engine Oil” underEngine Oil on page 5-16.
J. Hydraulic Clutch Reservoir (If Equipped)
(Not Shown). See “When to Check and What
to Use” underHydraulic Clutch on page 5-27.
K. Brake Master Cylinder Reservoir (Out of View).
See “Brake Fluid” underBrakes on page 5-41.
L. Engine Coolant Surge Tank and Pressure Cap.
SeeCoolant Surge Tank Pressure Cap on page 5-31
andCooling System on page 5-34.
M. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-21.
5-15

Brakes
Brake Fluid
The brake master cylinder
reservoir is lled with
DOT-3 brake uid. See
Engine Compartment
Overview on page 5-14for
the location of the reservoir.
There are only two reasons why the brake uid level in
the reservoir might go down. The rst is that the brake
uid goes down to an acceptable level during normal
brake lining wear. When new linings are put in, the uid
level goes back up. The other reason is that uid is
leaking out of the brake hydraulic system. If it is, 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 brake uid will 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 your vehicle has too much brake uid, it can
spill on the engine. The uid will burn if the
engine is hot enough. You or others could be
burned, and your vehicle could be damaged.
Add brake uid only when work is done on
the brake hydraulic system.
If the ignition is in ON/RUN and the brake uid is low,
the Service Brake System message will be displayed in
the DIC. SeeDIC Warnings and Messages on page 3-56.
When the brake uid falls to a low level, the brake
warning light will come on. SeeBrake System Warning
Light on page 3-38.
5-41

What to Add
DOT-3 brake uid is recommended. DOT-4 brake
uid is also compatible with your vehicle’s brake system
parts. However, if you choose to use DOT-4 uid, it is
recommended that you ush the brake hydraulic system
and rell it with new DOT-4 uid at a regular maintenance
service every two years. SeeAdditional Required
Services on page 6-6. Use new brake uid from a sealed
container only. SeeRecommended Fluids and Lubricants
on page 6-14.
Always clean the brake uid reservoir cap and the area
around the cap before removing it. This helps keep
dirt from entering the reservoir.
{CAUTION:
With the wrong kind of uid in the brake
hydraulic system, the brakes might not work
well. This could cause a crash. Always use the
proper brake uid.Notice:
Using the wrong uid can badly damage brake
hydraulic system parts. For example, just a
few drops of mineral-based oil, such as engine
oil, in the brake hydraulic system can damage
brake hydraulic system parts so badly that they
will have to be replaced. Do not let someone
put in the wrong kind of uid.
If you spill brake uid on your vehicle’s painted
surfaces, the paint nish can be damaged.
Be careful not to spill brake uid on your
vehicle. If you do, wash it off immediately.
SeeWashing Your Vehicle on page 5-116.
Brake Wear
Your 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 your vehicle is moving, except when you
are pushing on the brake pedal rmly.
5-42

{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 Specifications on page 5-129.
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.
Replacing Brake System Parts
The braking system on a vehicle is complex. Its many
parts have to be of top quality and work well together if
the vehicle is to have really good braking. Your vehicle
was designed and tested with top-quality brake parts.
When you replace parts of the braking system — for
example, when the brake linings wear down and you
need new ones put in — be sure you get new approved
replacement parts. If you do not, the brakes might not
work properly. For example, if someone puts in brake
linings that are wrong for your vehicle, the balance
between the front and rear brakes can change — for
the worse. The braking performance you have come to
expect can change in many other ways if someone puts
in the wrong replacement brake parts.
5-43

Jump Starting
If your vehicle’s battery has run down, you may want to
use another vehicle and some jumper cables to start
your vehicle. Be sure to use the following steps to do
it safely.
{CAUTION:
Batteries can hurt you. They can be dangerous
because:
They contain acid that can burn you.
They contain gas that can explode or
ignite.
They contain enough electricity to
burn you.
If you do not follow these steps exactly, some
or all of these things can hurt you.Notice:Ignoring these steps could result in costly
damage to your vehicle that would not be covered
by your warranty.
Trying to start your vehicle by pushing or pulling it
will not work, and it could damage your vehicle.
1. Check the other vehicle. It must have a 12-volt
battery with a negative ground system.
Notice:If the other vehicle’s system is not a 12-volt
system with a negative ground, both vehicles can
be damaged. Only use vehicles with 12-volt systems
with negative grounds to jump start your vehicle.
2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles are not touching
each other. If they are, it could cause a ground
connection you do not want. You would not be able
to start your vehicle and the bad grounding could
damage the electrical systems.
To avoid the possibility of the vehicles rolling, set
the parking brake rmly on both vehicles involved
in the jump start procedure. Put an automatic
transmission in P (Park) or a manual transmission
in NEUTRAL before setting the parking brake.
5-45

(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.
Tire Terminology and Denitions
Air Pressure:The amount of air inside the
tire pressing outward on each square inch of the
tire. Air pressure is expressed in pounds per
square inch (psi) or kilopascal (kPa).
Accessory Weight
:This means the combined
weight of optional accessories. Some examples of
optional accessories are, automatic transmission,
power steering, power brakes, power windows,
power seats, and air conditioning.
Aspect Ratio
:The relationship of a tire’s height
to its width.
Belt
:A rubber coated layer of cords that is
located between the plies and the tread. Cords
may be made from steel or other reinforcing
materials.
Bead
:The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the rim.
Bias Ply Tire
:A pneumatic tire in which the plies
are laid at alternate angles less than 90 degrees
to the centerline of the tread.
5-63

TPMS Sensor Matching Process
Each TPMS sensor has a unique identication code.
Any time you replace one or more of the TPMS sensors
or rotate your vehicle’s tires, the identication codes
need to be matched to the new tire/wheel position.
The sensors are matched to the tire/wheel positions
in the following order: driver side front tire, passenger
side front tire, passenger side rear tire, and driver
side rear tire using a TPMS diagnostic tool. See your
dealer/retailer for service.
The TPMS sensors can also be matched to each
tire/wheel position by increasing or decreasing the tire’s
air pressure. If increasing the tire’s air pressure, do not
exceed the maximum ination pressure indicated on the
tire’s sidewall. To decrease the tire’s air-pressure use the
pointed end of the valve cap, a pencil-style air pressure
gage, or a key.
You have two minutes to match the rst tire/wheel
position, and ve minutes overall, to match all four
tire/wheel positions. If it takes longer than two minutes,
to match the rst tire and wheel, or more than
ve minutes to match all four tire and wheel positions,
the matching process stops and you need to start over.The TPMS matching process is outlined below:
1. Set the parking brake.
2. Turn the ignition switch to ON/RUN with the
engine off.
3. Press the Remote Keyless Entry (RKE) transmitter’s
lock and unlock buttons at the same time for
approximately ve seconds. The horn sounds twice
to signal the receiver is in relearn mode and Tire
Learning Active message displays on the DIC
screen.
4. Start with the driver side front tire.
5. Remove the valve cap from the valve stem.
Activate the TPMS sensor by increasing or
decreasing the tire’s air pressure for 10 seconds,
or until a horn chirp sounds. The horn chirp, which
can take up to 30 seconds to sound, conrms
that the TPMS sensor identication code has
been matched to this tire position.
6. Proceed to the passenger side front tire, and repeat
the procedure in Step 5.
7. Proceed to the passenger side rear tire, and repeat
the procedure in Step 5.
8. Proceed to the driver side rear tire, and repeat the
procedure in Step 5.
5-73

You need new tires if any of the following statements
are true:
You can see the indicators at three or more places
around the tire.
You can see cord or fabric showing through the
tire’s rubber.
The tread or sidewall is cracked, cut, or snagged
deep enough to show cord or fabric.
The tire has a bump, bulge, or split.
The tire has a puncture, cut, or other damage that
cannot be repaired well because of the size or
location of the damage.
The rubber in tires degrades over time, even if they are
not being used. This is also true for the spare tire, if your
vehicle has one. Multiple conditions affect how fast this
aging takes place, including temperatures, loading
conditions, and ination pressure maintenance. With
proper care and maintenance tires will typically wear out
before they degrade due to age. If you are unsure about
the need to replace your tires as they get older, consult
the tire manufacturer for more information.
Buying New Tires
GM has developed and matched specic tires for your
vehicle. The original equipment tires installed on
your vehicle, when it was new, were designed to meet
General Motors Tire Performance Criteria Specication
(TPC Spec) system rating. If you need replacement
tires, GM strongly recommends that you get tires with
the same TPC Spec rating. This way, your vehicle
will continue to have tires that are designed to give
the same performance and vehicle safety, during
normal use, as the original tires.
GM’s exclusive TPC Spec system considers over a
dozen critical specications that impact the overall
performance of your vehicle, including brake system
performance, ride and handling, traction control, and
tire pressure monitoring performance. GM’s TPC Spec
number is molded onto the tire’s sidewall near the tire
size. If the tires have an all-season tread design, the
TPC Spec number will be followed by an MS for mud
and snow. SeeTire Sidewall Labeling on page 5-60
for additional information.
GM recommends replacing tires in sets of four. This is
because uniform tread depth on all tires will help keep
your vehicle performing most like it did when the tires
were new. Replacing less than a full set of tires can affect
the braking and handling performance of your vehicle.
SeeTire Inspection and Rotation on page 5-74for
information on proper tire rotation.
5-76