
Black plate (48,1)Cadillac STS Owner Manual - 2011
Back-Up Lamps
To replace a back-up lamp bulb:1. Open the trunk. See Trunk on page 3‑15.
2. Pull out the push pins holding down the top portion
of the cloth cover.
3. Fold the cover down slightly and locate the lamp assembly. 4. Turn the socket counterclockwise and pull it
straight out to remove it from the lamp assembly.
5. Pull the old bulb straight out and reinstall the new bulb.
6. Put the cover back in place and reinstall the push pins.
Replacement Bulbs
Exterior Lamp Bulb Number
Back-up 3157K
For replacement bulbs not listed here, contact your
dealer.
Windshield Replacement
The windshield is part of the Head-Up Display (HUD)
system. If you ever have to get the windshield replaced,
get one that is designed for HUD or the HUD image
may look out of focus.
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Black plate (56,1)Cadillac STS Owner Manual - 2011
Cold Tire Pressure:The amount of air pressure
in a tire, measured in pounds per square inch (psi)
or kilopascals (kPa) before a tire has built up heat
from driving. See Inflation - Tire Pressure
on
page 6‑58
.
Curb Weight
:The weight of a motor vehicle with
standard and optional equipment including the
maximum capacity of fuel, oil, and coolant, but
without passengers and cargo.
DOT Markings
:A code molded into the sidewall
of a tire signifying that the tire is in compliance
with the U.S. Department of Transportation (DOT)
motor vehicle safety standards. The DOT code
includes the Tire Identification Number (TIN), an
alphanumeric designator which can also identify
the tire manufacturer, production plant, brand, and
date of production.
GVWR
:Gross Vehicle Weight Rating. See
Loading the Vehicle
on page 5‑23.
GAWR FRT
:Gross Axle Weight Rating for the
front axle. See Loading the Vehicle
on page 5‑23.
GAWR RR
:Gross Axle Weight Rating for the rear
axle. See Loading the Vehicle
on page 5‑23. Intended Outboard Sidewall
:The side of an
asymmetrical tire, that must always face outward
when mounted on a vehicle.
Kilopascal (kPa)
:The metric unit for air pressure.
Light Truck (LT‐Metric) Tire
:A tire used on light
duty trucks and some multipurpose passenger
vehicles.
Load Index
:An assigned number ranging
from 1 to 279 that corresponds to the load
carrying capacity of a tire.
Maximum Inflation Pressure
:The maximum air
pressure to which a cold tire can be inflated. The
maximum air pressure is molded onto the
sidewall.
Maximum Load Rating
:The load rating for a tire
at the maximum permissible inflation pressure for
that tire.
Maximum Loaded Vehicle Weight
:The sum of
curb weight, accessory weight, vehicle capacity
weight, and production options weight.
Normal Occupant Weight
:The number of
occupants a vehicle is designed to seat multiplied
by 150 lbs (68 kg). See Loading the Vehicle
on
page 5‑23
.
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Black plate (57,1)Cadillac STS Owner Manual - 2011
Occupant Distribution:Designated seating
positions.
Outward Facing Sidewall
:The side of an
asymmetrical tire that has a particular side that
faces outward when mounted on a vehicle. The
side of the tire that contains a whitewall, bears
white lettering, or bears manufacturer, brand,
and/or model name molding that is higher or
deeper than the same moldings on the other
sidewall of the tire.
Passenger (P-Metric) Tire
:A tire used on
passenger cars and some light duty trucks and
multipurpose vehicles.
Recommended Inflation Pressure
:Vehicle
manufacturer's recommended tire inflation
pressure as shown on the tire placard. See
Inflation - Tire Pressure
on page 6‑58and Loading
the Vehicle
on page 5‑23.
Radial Ply Tire
:A pneumatic tire in which the ply
cords that extend to the beads are laid at
90 degrees to the centerline of the tread.
Rim
:A metal support for a tire and upon which
the tire beads are seated.
Sidewall
:The portion of a tire between the tread
and the bead. Speed Rating
:An alphanumeric code assigned
to a tire indicating the maximum speed at which a
tire can operate.
Traction
:The friction between the tire and the
road surface. The amount of grip provided.
Tread
:The portion of a tire that comes into
contact with the road.
Treadwear Indicators
:Narrow bands, sometimes
called wear bars, that show across the tread of
a tire when only 1/16 inch (1.6 mm) of tread
remains. See When It Is Time for New Tires
on
page 6‑67
.
UTQGS (Uniform Tire Quality Grading
Standards)
:A tire information system that
provides consumers with ratings for a tire's
traction, temperature, and treadwear. Ratings
are determined by tire manufacturers using
government testing procedures. The ratings are
molded into the sidewall of the tire. See Uniform
Tire Quality Grading
on page 6‑71.
Vehicle Capacity Weight
:The number of
designated seating positions multiplied by
150 lbs (68 kg) plus the rated cargo load.
See Loading the Vehicle
on page 5‑23.
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Black plate (62,1)Cadillac STS Owner Manual - 2011
Tire Pressure Monitor Operation
This vehicle may have a Tire Pressure Monitor System
(TPMS). The TPMS is designed to warn the driver when
a low tire pressure condition exists. TPMS sensors are
mounted onto each tire and wheel assembly, excluding
the spare tire and wheel assembly, if the vehicle has
one. The TPMS sensors monitor the air pressure in the
vehicle's tires and transmits the tire pressure readings
to a receiver located in the vehicle.
When a low tire pressure
condition is detected, the
TPMS illuminates the low
tire pressure warning light
located on the instrument
panel cluster.
If the warning light comes on, stop as soon as possible
and inflate the tires to the recommended pressure
shown on the tire loading information label. See
Loading the Vehicle on page 5‑23.
At the same time a message to check the pressure in a
specific tire appears on the Driver Information Center
(DIC) display. The low tire pressure warning light and
the DIC warning message come on at each ignition
cycle until the tires are inflated to the correct inflation
pressure. Using the DIC, tire pressure levels can be viewed by the driver. For additional information and
details about the DIC operation and displays see
DIC
Operation and Displays
on page 4‑70and DIC
Warnings and Messages on page 4‑76.
The low tire pressure warning light may come on in cool
weather when the vehicle is first started, and then turn
off as you start to drive. This could be an early indicator
that the air pressure in the tire(s) are getting low and
need to be inflated to the proper pressure.
A Tire and Loading Information label , attached to your
vehicle, shows the size of your vehicle's original
equipment tires and the correct inflation pressure for
your vehicle's tires when they are cold. See Loading the
Vehicle
on page 5‑23for an example of the Tire and
Loading Information label and its location on your
vehicle. Also see Inflation - Tire Pressure
on
page 6‑58.
Your vehicle's TPMS can warn you about a low tire
pressure condition but it does not replace normal tire
maintenance. See Tire Inspection and Rotation
on
page 6‑65and Tires on page 6‑50.
Notice: Using non‐approved tire sealants could
damage the Tire Pressure Monitor System (TPMS)
sensors. TPMS sensor damage caused by using an
incorrect tire sealant is not covered by the vehicle
warranty. Always use the GM approved tire sealant
available through your dealer.
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Black plate (63,1)Cadillac STS Owner Manual - 2011
Factory-installed Tire Inflator Kits use a GM approved
liquid tire sealant. Using non-approved tire sealants
could damage the TPMS sensors. SeeTire Sealant and
Compressor Kit (Without Selector Switch)
on
page 6‑76or Tire Sealant and Compressor Kit (With
Selector Switch)on page 6‑85for information
regarding the inflator kit materials and instructions.
TPMS Malfunction Light and Message
The TPMS will not function properly if one or more of
the TPMS sensors are missing or inoperable. When the
system detects a malfunction, the low tire warning light
flashes for about one minute and then stays on for the
remainder of the ignition cycle. A DIC warning message
is also displayed. The low tire warning light and DIC
warning message come on at each ignition cycle until
the problem is corrected. Some of the conditions that
can cause the malfunction light and DIC message to
come on are:
.One of the road tires has been replaced with the
spare tire, if the vehicle has one. The spare tire
does not have a TPMS sensor. The DIC message
should go off once you re‐install the road tire
containing the TPMS sensor.
.The TPMS sensor matching process was started
but not completed or not completed successfully
after rotating the vehicle's tires. The DIC message
and TPMS malfunction light should go off once the
TPMS sensor matching process is performed
successfully. See “TPMS Sensor Matching
Process” later in this section.
.One or more TPMS sensors are missing or
damaged. The DIC message and the TPMS
malfunction light should go off when the TPMS
sensors are installed and the sensor matching
process is performed successfully. See your dealer
for service.
.Replacement tires or wheels do not match your
vehicle's original equipment tires or wheels. Tires
and wheels other than those recommended for
your vehicle could prevent the TPMS from
functioning properly. See Buying New Tires
on
page 6‑67.
.Operating electronic devices or being near facilities
using radio wave frequencies similar to the TPMS
could cause the TPMS sensors to malfunction.
If the TPMS is not functioning it cannot detect or signal
a low tire condition. See your dealer for service if the
TPMS malfunction light and DIC message comes on
and stays on.
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Black plate (66,1)Cadillac STS Owner Manual - 2011
When rotating P235/50R17 size tires or
255/45ZR18 size tires, always use the correct
rotation pattern shown here.
If the vehicle has a compact spare tire, do not
include the compact spare tire in the tire rotation.
After the tires have been rotated, adjust the front
and rear inflation pressures as shown on the Tire
and Loading Information label. SeeInflation - Tire
Pressure
on page 6‑58and Loading the Vehicleon
page 5‑23
.
Reset the Tire Pressure Monitor System. See Tire
Pressure Monitor Operation
on page 6‑62. Make certain that all wheel nuts are properly
tightened. See
“Wheel Nut Torque” under
Capacities and Specifications
on page 6‑128.
{WARNING:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after time. The wheel could
come off and cause an accident. When you
change a wheel, remove any rust or dirt from
places where the wheel attaches to the
vehicle. In an emergency, you can use a
cloth or a paper towel to do this; but be
sure to use a scraper or wire brush later,
if needed, to get all the rust or dirt off. See
Changing a Flat Tire
on page 6‑94.
Lightly coat the center of the wheel hub with
wheel bearing grease after a wheel change or tire
rotation to prevent corrosion or rust build-up. Do
not get grease on the flat wheel mounting surface
or on the wheel nuts or bolts.
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Black plate (67,1)Cadillac STS Owner Manual - 2011
When It Is Time for New Tires
Various factors, such as maintenance, temperatures,
driving speeds, vehicle loading, and road conditions
influence when you need new tires.
One way to tell when it is
time for new tires is to
check the treadwear
indicators, which will
appear when your tires
have only 1/16 inch
(1.6 mm) or less of tread
remaining. SeeTire
Inspection and Rotation
on page 6‑65for
additional information.
The rubber in tires ages 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 inflation pressure maintenance. Tires
will typically need to be replaced due to wear before
they may need to be replaced due to age. Consult the
tire manufacturer for more information on when tires
should be replaced.
Vehicle Storage
Tires age when stored normally mounted on a parked
vehicle. Park a vehicle that will be stored for at least a
month in a cool, dry, clean area away from direct
sunlight to slow aging. This area should be free of
grease, gasoline or other substances that can
deteriorate rubber.
Parking for an extended period can cause flat spots on
the tires that may result in vibrations while driving.
When storing a vehicle for at least a month, remove the
tires or raise the vehicle to reduce the weight from the
tires.
Buying New Tires
GM has developed and matched specific 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
Specification (TPC Spec) system rating. If you
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Black plate (71,1)Cadillac STS Owner Manual - 2011
Uniform Tire Quality Grading
Quality grades can be found where applicable on
the tire sidewall between tread shoulder and
maximum section width. For example:
Treadwear 200 Traction AA
Temperature A
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration (NHTSA), which
grades tires by treadwear, traction, and
temperature performance. This applies only to
vehicles sold in the United States. The grades are
molded on the sidewalls of most passenger car
tires. The Uniform Tire Quality Grading (UTQG)
system does not apply to deep tread, winter-type
snow tires, space-saver, or temporary use spare
tires, tires with nominal rim diameters of
10 to 12 inches (25 to 30 cm), or to some
limited-production tires.
While the tires available on General Motors
passenger cars and light trucks may vary with
respect to these grades, they must also conform
to federal safety requirements and additional
General Motors Tire Performance Criteria (TPC)
standards.All Passenger Car Tires Must Conform to Federal
Safety Requirements In Addition To These
Grades.
Treadwear
The treadwear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a specified
government test course. For example, a tire
graded 150 would wear one and a half (1½) times
as well on the government course as a tire graded
100. The relative performance of tires depends
upon the actual conditions of their use, however,
and may depart significantly from the norm due to
variations in driving habits, service practices and
differences in road characteristics and climate.
Traction
–AA, A, B, C
The traction grades, from highest to lowest,
are AA, A, B, and C. Those grades represent
the tire's ability to stop on wet pavement as
measured under controlled conditions on specified
government test surfaces of asphalt and concrete.
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