2009 CADILLAC STS wheel

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
ashes 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/retailer 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. SeeBuying New Tires on page 5-74.
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/retailer for
service if the TPMS malfunction light and DIC message
comes on and stays on.
5-69

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
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 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 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. If using this method to match TPMS
sensors, the complete procedure outlined below must
be performed within 15 minutes of the vehicle being
stationary.
To decrease air-pressure out of a tire you can use the
pointed end of the valve cap, a pencil-style air pressure
gage, or a key.
You will have one minute to match the rst tire/wheel
position, and ve minutes overall, to match all four
tire/wheel positions. If it takes longer than one minute to
match the rst tire and wheel, or more than ve minutes
to match all four tire/wheel positions, the matching
process stops and you will need to start over.The TPM matching process is outlined below:
1. Set the parking brake.
2. Press the push-button ignition switch to Acc.
3. Using the keyless access transmitter, lock and
unlock the vehicle’s doors.
4. Press the lock and unlock buttons, at the same
time, on the keyless access transmitter. The horn
sounds twice, indicating that the TPMS is ready,
and the sensor matching process can begin.
5. Start with the driver side front tire.
6. Remove the valve cap from the 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 this tire position.
7. Proceed to the passenger side front tire, and repeat
the procedure in Step 6.
8. Proceed to the passenger side rear tire, and repeat
the procedure in Step 6.
9. Proceed to the driver side rear tire, and repeat the
procedure in Step 6.
10. After hearing the conrming single horn chirp for the
driver side rear tire, a double horn chirp will sound to
signal the tire matching mode is no longer active.
Press the push-button ignition switch to Acc.
5-70

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.
Tire Inspection and Rotation
We recommend that you regularly inspect your
vehicle’s tires, including the spare tire, for signs
of wear or damage. SeeWhen It Is Time for
New Tires on page 5-73for more information.
Tire rotation is not recommended if your vehicle
has the following performance tire combinations:
P235/50R17 size tires on the front wheels
and P255/45R17 size tires on the rear wheels.
P235/50ZR18 size tires on the front wheels
and P255/45ZR18 size tires on the rear
wheels.
P255/45R18 size tires on the front wheels and
P275/40R19 size tires on the rear wheels.Different tire sizes should not be rotated front to
rear. Each tire and wheel should only be used
in the original front or rear position it is in.
Tire rotation is recommended if the vehicle is
equipped with P235/50R17 size tires on all four
wheel positions or 255/45ZR18 size tires on all
four wheel positions. These tires should be rotated
every 5,000 to 8,000 miles (8 000 to 13 000 km).
SeeScheduled Maintenance on page 6-4.
The purpose of a regular tire rotation is to achieve
a uniform wear for all tires on the vehicle. This
will ensure that the vehicle continues to perform
most like it did when the tires were new.
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 5-73
andWheel Replacement on page 5-79.
5-71

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 ination pressures as shown on the Tire
and Loading Information label. SeeInflation - Tire
Pressure on page 5-64andLoading the Vehicle on
page 4-24.Reset the Tire Pressure Monitor System. SeeTire
Pressure Monitor Operation on page 5-68.
Make certain that all wheel nuts are properly
tightened. See “Wheel Nut Torque” under
Capacities and Specifications on page 5-134.
{CAUTION:
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. SeeChanging a Flat Tire on
page 5-104.
5-72

{CAUTION:
Mixing tires could cause you to lose control while
driving. If you mix tires of different sizes (other than
those originally installed on your vehicle), brands, or
types (radial and bias-belted tires), the vehicle may
not handle properly, and you could have a crash.
Using tires of different sizes (other than those
originally installed on your vehicle), brands, or types
may also cause damage to your vehicle. Be sure to
use the correct size, brand, and type of tires on all
wheels. It is all right to drive with your vehicle’s
compact spare temporarily, it was developed for
use on your vehicle. SeeCompact Spare Tire on
page 5-114.
{CAUTION:
If you use bias-ply tires on the vehicle, the
wheel rim anges could develop cracks after
many miles of driving. A tire and/or wheel
could fail suddenly, causing a crash. Use
only radial-ply tires with the wheels on the
vehicle.
If you must replace your vehicle’s tires with those
that do not have a TPC Spec number, make sure
they are the same size, load range, speed rating,
and construction type (radial and bias-belted tires)
as your vehicle’s original tires.
Vehicles that have a tire pressure monitoring
system could give an inaccurate low-pressure
warning if non-TPC Spec rated tires are installed
on it. Non-TPC Spec rated tires may give a
low-pressure warning that is higher or lower
than the proper warning level you would get with
TPC Spec rated tires. SeeTire Pressure Monitor
System on page 5-66.
5-75

Your vehicle’s original equipment tires are
listed on the Tire and Loading Information label.
SeeLoading the Vehicle on page 4-24, for
more information about the Tire and Loading
Information label and its location on your vehicle.
Different Size Tires and Wheels
If you add wheels or tires that are a different size than
your original equipment wheels and tires, this may affect
the way your vehicle performs, including its braking, ride
and handling characteristics, stability, and resistance
to rollover. Additionally, if your vehicle has electronic
systems such as, antilock brakes, traction control, and
electronic stability control, the performance of these
systems can be affected.
{CAUTION:
If you add different sized wheels, your vehicle may
not provide an acceptable level of performance and
safety if tires not recommended for those wheels
are selected. You may increase the chance that you
will crash and suffer serious injury. Only use GM
specic wheel and tire systems developed for your
vehicle, and have them properly installed by a GM
certied technician.
SeeBuying New Tires on page 5-74andAccessories
and Modifications on page 5-3for additional information.
5-76

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 specied government test
surfaces of asphalt and concrete. A tire marked C
may have poor traction performance.
{WARNING:
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration,
cornering, hydroplaning, or peak traction
characteristics.
Temperature – A, B, C
The temperature grades are A (the highest), B,
and C, representing the tire’s resistance to the
generation of heat and its ability to dissipate heat
when tested under controlled conditions on a
specied indoor laboratory test wheel. Sustained
high temperature can cause the material of the tire
to degenerate and reduce tire life, and excessive
temperature can lead to sudden tire failure. The
grade C corresponds to a level of performance
which all passenger car tires must meet under the
Federal Motor Vehicle Safety Standard No. 109.
Grades B and A represent higher levels of
performance on the laboratory test wheel than
the minimum required by law.
{WARNING:
The temperature grade for this tire is
established for a tire that is properly inated
and not overloaded. Excessive speed,
underination, or excessive loading, either
separately or in combination, can cause
heat buildup and possible tire failure.
5-78

Wheel Alignment and Tire Balance
The tires and wheels on your vehicle were aligned and
balanced carefully at the factory to give you the longest
tire life and best overall performance. Adjustments to
wheel alignment and tire balancing will not be necessary
on a regular basis. However, if you notice unusual tire
wear or your vehicle pulling to one side or the other, the
alignment might need to be checked. If you notice your
vehicle vibrating when driving on a smooth road, the tires
and wheels might need to be rebalanced. See your
dealer/retailer for proper diagnosis.
Wheel Replacement
Replace any wheel that is bent, cracked, or badly rusted
or corroded. If wheel nuts keep coming loose, the wheel,
wheel bolts, and wheel nuts should be replaced. If the
wheel leaks air, replace it (except some aluminum
wheels, which can sometimes be repaired). See your
dealer/retailer if any of these conditions exist.
Your dealer/retailer will know the kind of wheel
you need.
Each new wheel should have the same load-carrying
capacity, diameter, width, offset, and be mounted
the same way as the one it replaces.
5-79