
Black plate (33,1)Cadillac STS Owner Manual - 2011
Power Steering Fluid
SeeEngine Compartment
Overviewon page 6‑13for reservoir location.
When to Check Power Steering Fluid
It is not necessary to regularly check power steering
fluid unless you suspect there is a leak in the system or
you hear an unusual noise. A fluid loss in this system
could indicate a problem. Have the system inspected
and repaired.
How to Check Power Steering Fluid
To check the power steering fluid, do the following:
1. Turn the ignition off and let the engine compartment cool down.
2. Wipe the cap and the top of the reservoir clean.
3. Unscrew the cap and wipe the dipstick with a clean rag.
4. Replace the cap and completely tighten it.
5. Remove the cap again and look at the fluid level on the dipstick.
The level should be within the HOT mark. If necessary,
add only enough fluid to bring the level within the mark.
What to Use
To determine what kind of fluid to use, see
Recommended Fluids and Lubricantson page 7‑9.
Always use the proper fluid.
Notice: Use of the incorrect fluid may damage the
vehicle and the damages may not be covered by the
vehicle's warranty. Always use the correct fluid
listed in Recommended Fluids and Lubricants
on
page 7‑9.
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Black plate (55,1)Cadillac STS Owner Manual - 2011
(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 index and speed rating of the
tire. The load index represents the load carrying
capacity a tire is certified to carry. The speed
rating is the maximum speed a tire is certified to
carry a load.
Tire Terminology and Definitions
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.
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Black plate (74,1)Cadillac STS Owner Manual - 2011
Tire Chains
{WARNING:
If your vehicle has P255/45R17, P255/45ZR18,
or 255/45ZR18 size tires, do not use tire chains,
as there is not enough clearance.
Tire chains used on a vehicle without the proper
amount of clearance can cause damage to the
brakes, suspension, or other vehicle parts. The
area damaged by the tire chains could cause you
to lose control of the vehicle and you or others
may be injured in a crash.
Use another type of traction device only if its
manufacturer recommends it for use on your
vehicle and tire size combination and road
conditions. Follow that manufacturer's
instructions. To help avoid damage to the vehicle,
drive slowly, readjust, or remove the device if it is
contacting the vehicle, and do not spin the
vehicle's wheels.
If you do find traction devices that will fit, install
them on the rear tires only.Notice:
If your vehicle has P235/50R17 size tires,
use tire chains only where legal and only when you
must. Use only SAE Class S‐type chains that are the
proper size for your tires. Install them on the rear
tires and tighten them as tightly as possible with the
ends securely fastened. Drive slowly and follow the
chain manufacturer's instructions. If you can hear
the chains contacting your vehicle, stop and
retighten them. If the contact continues, slow down
until it stops. Driving too fast or spinning the wheels
with chains on will damage your vehicle.
If a Tire Goes Flat
It is unusual for a tire to blowout while you are driving,
especially if you maintain your vehicle's tires properly.
If air goes out of a tire, it is much more likely to leak out
slowly. But if you should ever have a blowout, here are
a few tips about what to expect and what to do:
If a front tire fails, the flat tire creates a drag that pulls
the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel firmly.
Steer to maintain lane position, and then gently brake to
a stop, well off the road, if possible.
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Black plate (75,1)Cadillac STS Owner Manual - 2011
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you would
use in a skid. In any rear blowout remove your foot from
the accelerator pedal. Get the vehicle under control by
steering the way you want the vehicle to go. It may be
very bumpy and noisy, but you can still steer. Gently
brake to a stop, well off the road, if possible.
{WARNING:
Driving on a flat tire will cause permanent damage
to the tire. Re-inflating a tire after it has been
driven on while severely under-inflated or flat may
cause a blowout and a serious crash. Never
attempt to re-inflate a tire that has been driven on
while severely under-inflated or flat. Have your
dealer or an authorized tire service center repair
or replace the flat tire as soon as possible.
{WARNING:
Lifting a vehicle and getting under it to do
maintenance or repairs is dangerous without the
appropriate safety equipment and training. If a
jack is provided with the vehicle, it is designed
only for changing a flat tire. If it is used for
anything else, you or others could be badly
injured or killed if the vehicle slips off the jack. If a
jack is provided with the vehicle, only use it for
changing a flat tire.
This vehicle may come with a jack and spare tire or a
tire sealant and compressor kit. To use the jack and
spare tire, see Changing a Flat Tire
on page 6‑94. To
use the tire sealant and compressor kit, see Tire
Sealant and Compressor Kit (Without Selector Switch)
on page 6‑76or Tire Sealant and Compressor Kit (With
Selector Switch)on page 6‑85.
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Black plate (117,1)Cadillac STS Owner Manual - 2011
The underhood fuse block is located in the front of the
engine compartment on the passenger side of the
vehicle. SeeEngine Compartment Overview
on
page 6‑13for more information on location and
removal procedure for the front compartment underhood
sights shields.
To access the fuses, push in the tabs located on each
side of the fuse block cover, then lift the cover off.
Notice: Spilling liquid on any electrical component
on the vehicle may damage it. Always keep the
covers on any electrical component.
Fuses JCase Usage
ABS MTR ABS Module- ABS Module-Stabilitrak AFS Active Front Steering
BLWR Blower Motor
FAN 1 Cooling Fan-Low Speed
FAN 2 Cooling Fan-High Speed
LPDB 1 Driver Side Rear Fuse Block
LPDB 2 Driver Side Rear Fuse Block
RPDB 1 Passenger Side Rear Fuse Block
RPDB 2 Passenger Side Rear Fuse Block
Fuses JCase Usage
SPARE Spare
SPARE Spare
STRTR Starter
Fuses MiniUsage
A/C CLTCH Air Conditioning Compressor Clutch
ABS ABS Module-Stabilitrak
ABS IGN Antilock Brake Controller
AUX OUTLET Rear Accessory Power Outlet BRK
VAC PUMP Brake Vacuum Pump
CCP Climate Control Panel
CCP/RLY COILS Climate Control Panel, Headlamp
Level Control, Active Cruise Control,
Relay Coils, Starter, Front Blower
ECM 1 Engine Control Module (ECM)
ECM/TCM BATT ECM, Transmission Control
Module (TCM)
ECM/TCM IGN ECM, TCM, Instrument Panel Cluster
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Black plate (118,1)Cadillac STS Owner Manual - 2011
Fuses MiniUsage
EKM/I/P MDLEasy Key Module (EKM), Instrument
Panel Module (I/P MDL)
EVEN COILS Even Ignition Coils, Even Fuel
Injectors
FOG LAMP Front Fog Lamps
FRT PWR OUTLET Front Accessory Power Outlet
FUEL COOL Fuel Cooling HORN Horn
HTD
WASH/AQS Heated Headlamp Washer, Air Quality
Sensor
HUD Heads-Up Display, Steering Column
Switch
I/BEAM IntelliBeam Relay
I/P MDL/ALDL Instrument Panel Module, Assembly
Line Data Link Connector
LIC DIM License Plate, Instrument Panel
Dimming
LT HI BEAM Driver Side High Beam Headlamp
LT LO BEAM Driver Side Low Beam Headlamp
Fuses Mini Usage
LT PRKDriver Side Park Lamp/Driver Side
Taillamp
ODD COILS Odd Ignition Coils, Odd Fuel Injectors
POST O2 SNSR Post Oxygen Sensor PRE O2 SNSR Pre Oxygen Sensor, CAM Sensors
RAIN
SNSR/TPM Rain Sensor, Relay Coil:
Headlamp Wash
RT HI BEAM Passenger Side High Beam
Headlamp
RT LO BEAM Passenger Side Low Beam Headlamp
RT PRK Passenger Side Park Lamp,
Passenger Side Taillamp
SPARE Spare
SPARE Spare
SPARE Spare
SPARE Spare
SPARE Spare
SPARE Spare
SPARE Spare
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Black plate (126,1)Cadillac STS Owner Manual - 2011
FusesUsage
AIRBAG/IGNSensing and Diagnostic Monitor,
Automatic Occupant Sensor,
Passenger Supplemental Inflatable
Restraint
CNSTR/VENT Canister Vent Solenoid
SPARE Spare
FRT PDM Front Passenger Door Module, Right
Power Subwoofer
FUEL PUMP Fuel Pump
HTD STR Heated Steering WheelRF HTD/
SEAT/XM Front Passenger Heated Seat,
S-Band™
Antenna
RDO/ONSTAR Radio, OnStar
®
INT LAMP Interior Lamps
LT TRN/LDW Left Turn Signal, Lane Departure
Warning (Option)
Fuses
Usage
REAR DEFOG Rear Defogger
REAR/FOG Rear Fog Lamps (Option)
RIM Rear Integration Module
RIM /RPA
/ISRVM /CLM Rear Integration Module, Rear
Parking Aid, Inside Rearview Mirror,
Column Lock Module, Power
Sounder, Active Front Steering (AFS),
Supervisory Control Module
RUN/CRNK UHBEC Run, CRNK Relay Coil, Rear
Fog Lamp Relay Coil
S/ROOF Sun Roof Module (Option) SPARE Spare
STOP LAMPS Stop Lamps
RT TRN/SZBA Right Turn Signal, Side Blind Zone
Alert (Option)
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Black plate (4,1)Cadillac STS Owner Manual - 2011
Every Engine Oil Change
.Change engine oil and filter. Reset oil life system.
SeeEngine Oilon page 6‑16andEngine Oil Life
Systemon page 6‑20. An Emission Control
Service.
.Engine coolant level check. See Engine Coolanton page 6‑25.
.Engine cooling system inspection. Visual
inspection of hoses, pipes, fittings, and clamps and
replacement, if needed.
.Windshield washer fluid level check. See
Windshield Washer Fluid on page 6‑34.
.Windshield wiper blade inspection for wear,
cracking, or contamination and windshield and
wiper blade cleaning, if contaminated. See
Windshield and Wiper Blades
on page 6‑111. Worn
or damaged wiper blade replacement. See
Windshield Wiper Blade Replacement
on
page 6‑49.
.Tire inflation pressures check. See Inflation - Tire
Pressure on page 6‑58.
.Tire wear inspection. See Tire Inspection and
Rotation on page 6‑65.
.If tire rotation is recommended for the vehicle,
rotate tires if necessary. See Tire Inspection and
Rotation on page 6‑65.
.Fluids visual leak check (or every 12 months,
whichever occurs first). A leak in any system must
be repaired and the fluid level checked.
.Engine air cleaner filter inspection. See Engine Air
Cleaner/Filter on page 6‑21.
.Brake system inspection (or every 12 months,
whichever occurs first).
.Steering and suspension inspection. Visual
inspection for damaged, loose, or missing parts
or signs of wear.
.Body hinges and latches, key lock cylinders,
rear compartment hinges, console door hinges,
and glove box door hinges lubrication. See
Recommended Fluids and Lubricants
on
page 7‑9. More frequent lubrication may be
required when the vehicle is exposed to a
corrosive environment. Applying silicone grease
on weatherstrips with a clean cloth makes them
last longer, seal better, and not stick or squeak.
.Restraint system component check. See Checking
the Restraint Systems on page 2‑72.
.Fuel system inspection for damage or leaks.
.Exhaust system and nearby heat shields
inspection for loose or damaged components.
7-4