Page 382 of 528

Black plate (32,1)Cadillac STS Owner Manual - 2011
If the engine coolant temperature gauge is no longer in
the overheat zone or an overheat warning no longer
displays, the vehicle can be driven. Continue to drive
the vehicle slow for about 10 minutes. Keep a safe
vehicle distance from the car in front of you. If the
warning does not come back on, continue to drive
normally.
If the warning continues, pull over, stop, and park the
vehicle right away.
If there is no sign of steam, idle the engine for
three minutes while parked. If the warning is still
displayed, turn off the engine until it cools down. Also,
see "Overheated Engine Protection Operating Mode"
later in this section.Overheated Engine Protection
Operating Mode
This operating mode allows your vehicle to be driven to
a safe place in an emergency. Should an overheated
engine condition exist, an overheat protection mode
which alternates firing groups of cylinders helps prevent
engine damage. In this mode, you will notice a loss in
power and engine performance. An engine overheat
warning will indicate that an overheat condition exists.
Driving extended miles (km) and/or towing a trailer in
the overheat protection mode should be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any
repair. The engine oil will be severely degraded.
Repair the cause of coolant loss and change the oil.
See Engine Oil on page 6‑16.
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Page 384 of 528

Black plate (34,1)Cadillac STS Owner Manual - 2011
Windshield Washer Fluid
What to Use
When you need windshield washer fluid, be sure to
read the manufacturer's instructions before use. If you
will be operating your vehicle in an area where the
temperature may fall below freezing, use a fluid that has
sufficient protection against freezing.
Adding Washer Fluid
The CHECK WASHER FLUID message will appear on
the Driver Information Center (DIC) when the fluid level
is low. SeeDIC Warnings and Messages
on page 4‑76for more information.
Open the cap with the
washer symbol on it.
Add washer fluid until the
tank is full. See Engine
Compartment Overview
on page 6‑13for
reservoir location.
Notice:
.When using concentrated washer fluid,
follow the manufacturer's instructions for
adding water.
.Do not mix water with ready-to-use washer
fluid. Water can cause the solution to freeze
and damage the washer fluid tank and other
parts of the washer system. Also, water does
not clean as well as washer fluid.
.Fill the washer fluid tank only three-quarters
full when it is very cold. This allows for fluid
expansion if freezing occurs, which could
damage the tank if it is completely full.
.Do not use engine coolant (antifreeze) in
the windshield washer. It can damage the
windshield washer system and paint.
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Page 385 of 528

Black plate (35,1)Cadillac STS Owner Manual - 2011
Brakes
Brake Fluid
The brake master cylinder
reservoir is filled with DOT
3 brake fluid. SeeEngine
Compartment Overview
on page 6‑13for
reservoir location and
access.
There are only two reasons why the brake fluid level in
the reservoir might go down:
.The brake fluid level goes down because of
normal brake lining wear. When new linings are
installed, the fluid level goes back up.
.A fluid leak in the brake hydraulic system can also
cause a low fluid level. Have the brake hydraulic
system fixed, since a leak means that sooner or
later the brakes will not work well. Do not top off the brake fluid. Adding fluid does not
correct a leak. If fluid is added when the linings are
worn, there will be too much fluid when new brake
linings are installed. Add or remove brake fluid, as
necessary, only when work is done on the brake
hydraulic system.
{WARNING:
If too much brake fluid 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 fluid only when work is
done on the brake hydraulic system.
If the ignition is on and the brake fluid is low, the
CHECK BRAKE FLUID message displays in the Driver
Information Center (DIC). See DIC Warnings and
Messages on page 4‑76.
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Page 386 of 528

Black plate (36,1)Cadillac STS Owner Manual - 2011
What to Add
DOT 3 brake fluid is recommended. DOT 4 brake fluid
is also compatible with the vehicle's brake system parts.
However, if DOT 4 fluid is used, it is recommended that
the brake hydraulic system be flushed and refilled with
new DOT 4 fluid at a regular maintenance service every
two years. SeeScheduled Maintenance
on page 7‑3.
Use new brake fluid from a sealed container only. See
Recommended Fluids and Lubricants on page 7‑9.
Always clean the brake fluid reservoir cap and the area
around the cap before removing it. This helps keep dirt
from entering the reservoir.
{WARNING:
With the wrong kind of fluid in the brake hydraulic
system, the brakes might not work well. This could
cause a crash. Always use the proper brake fluid. Notice:
.Using the wrong fluid 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
fluid.
.If brake fluid is spilled on the vehicle's
painted surfaces, the paint finish can be
damaged. Be careful not to spill brake fluid
on the vehicle. If you do, wash it off
immediately. See
Washing Your Vehicle
on
page 6‑109
.
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 firmly.
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Page 387 of 528

Black plate (37,1)Cadillac STS Owner Manual - 2011
{WARNING:
The brake wear warning sound means that soon
the brakes will not work well. That could lead to a
crash. 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 first 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 specifications in
Capacities and Specifications on page 6‑128.
Brake linings should always be replaced as complete
axle sets.
Brake Pedal Travel
See your dealer 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.
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. The vehicle
was designed and tested with top-quality brake parts.
When parts of the braking system are replaced —for
example, when the brake linings wear down and new
ones are installed —be sure to get new approved
replacement parts. If this is not done, the brakes might
not work properly. For example, if someone puts in
brake linings that are wrong for the vehicle, the balance
between the front and rear brakes can change —for the
worse. The braking performance expected can change
in many other ways if the wrong replacement brake
parts are installed.
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Page 388 of 528

Black plate (38,1)Cadillac STS Owner Manual - 2011
Battery
Refer to the replacement number on the original battery
label when a new battery is needed. SeeEngine
Compartment Overview
on page 6‑13for battery
location.
{DANGER:
Battery posts, terminals, and related accessories
contain lead and lead compounds, chemicals
known to the State of California to cause cancer
and reproductive harm. Wash hands after
handling.
Vehicle Storage
{WARNING:
Batteries have acid that can burn you and gas
that can explode. You can be badly hurt if you are
not careful. See Jump Starting
on page 6‑38for
tips on working around a battery without
getting hurt. Infrequent Usage: Remove the black, negative (−) cable
from the battery to keep the battery from running down.
Extended Storage: Remove the black, negative (−)
cable from the battery or use a battery trickle charger.
Jump Starting
For more information about the vehicle battery, see
Battery on page 6‑38.
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.
{WARNING:
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.
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Page 390 of 528
Black plate (40,1)Cadillac STS Owner Manual - 2011
Your vehicle has a remote negative (−) ground
location, as shown in the illustration. It is located
on the passenger side front shock tower. See
Engine Compartment Overview
on page 6‑13.
You should always use this remote ground
location, instead of the terminal on the battery. Notice:
If you connect a negative cable to the
Engine Control Module (ECM), ECM mounting
bracket, or any cables that attach to the ECM
bracket, you may damage the ECM. Always attach
the negative cable to your vehicle's remote negative
ground location, instead of the ECM, ECM bracket,
or any cables attached to the ECM bracket.
{WARNING:
An electric fan can start up even when the engine
is not running and can injure you. Keep hands,
clothing and tools away from any underhood
electric fan.
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Page 391 of 528

Black plate (41,1)Cadillac STS Owner Manual - 2011
{WARNING:
Using an open flame near a battery can cause
battery gas to explode. People have been hurt
doing this, and some have been blinded. Use a
flashlight if you need more light.
Be sure the battery has enough water. You do not
need to add water to the battery installed in your
new vehicle. But if a battery has filler caps, be
sure the right amount of fluid is there. If it is low,
add water to take care of that first. If you do not,
explosive gas could be present.
Battery fluid contains acid that can burn you. Do
not get it on you. If you accidentally get it in your
eyes or on your skin, flush the place with water
and get medical help immediately.
{WARNING:
Fans or other moving engine parts can injure you
badly. Keep your hands away from moving parts
once the engine is running.
5. Check that the jumper cables do not have loose or missing insulation. If they do, you could get a
shock. The vehicles could be damaged too.
Before you connect the cables, here are some
basic things you should know. Positive (+) will go to
positive (+) or to a remote positive (+) terminal if
the vehicle has one. Negative (−) will go to a
heavy, unpainted metal engine part or to a remote
negative (−) terminal if the vehicle has one.
Do not connect positive (+) to negative (−) or you
will get a short that would damage the battery and
maybe other parts too. And do not connect the
negative (−) cable to the negative (−) terminal on
the dead battery because this can cause sparks.
6-41