2006 CADILLAC STS service

Tire Size
The following illustration shows an example of a typical
passenger vehicle tire size.
(A) Passenger (P-Metric) Tire:The United States
version of a metric tire sizing system. The letter P as the
rst character in the tire size means a passenger vehicle
tire engineered to standards set by the U.S. Tire and Rim
Association.
(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.
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Run-Flat Tires (STS-V)
If your vehicle has run-at tires, there is no spare tire
and no tire changing equipment. Your vehicle also has a
Tire Pressure Monitor System (TPMS) which will alert
you if there is a loss of tire pressure in any of the tires.
SeeTire Pressure Monitor System on page 5-66.
{CAUTION:
When the low tire warning light is displayed on
the instrument panel cluster, your vehicle’s
handling capabilities will be reduced during
severe maneuvers. If you drive too fast, you
could lose control of your vehicle. You or
others could be injured. Do not drive over
55 mph (90 km/h) when the low tire warning
light is displayed. Drive cautiously and check
your tire pressures as soon as you can.If a tire goes at, you will not need to stop on the side
of the road to change the tire. You can just keep on
driving. The vehicle’s run-at tires can operate effectively
with no air pressure for up to 50 miles (80 km) at
speeds up to 55 mph (90 km/h). The shorter the
distance you drive and the slower the speed, the greater
the chance that the tire will not have to be replaced.
When a tire is lled with air, it provides a cushion
between the road and the wheel. Because you will not
have this cushion when driving on a deated run-at
tire, try to avoid potholes that could damage your wheel
and require replacement of it.
Some road hazards can damage a tire beyond repair.
This damage could occur even before you have driven
on the tire in a deated condition. When a tire has been
damaged, or if you have driven any distance on a
deated run-at tire, check with an authorized run-at
tire service center, as soon as possible, to determine
whether the tire can be repaired or should be replaced.
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To maintain your vehicle’s run-at feature, all
replacement tires must be self-supporting tires.
To locate the nearest GM or authorized run-at
servicing facility, call Roadside Service. See
Roadside Service on page 7-5for details.
{CAUTION:
Run-at tires are constructed differently than
other tires and could explode during improper
service. You or others could be injured or
killed if you attempt to repair, replace,
dismount, or mount a run-at tire. Let only
an authorized run-at service center repair,
replace, dismount, and mount run-at tires.
The valve stems on your vehicle’s run-at tires have
sensors that are part of the Tire Pressure Monitor
System (TPMS). These sensors contain batteries which
are designed to last for 10 years under normal driving
conditions. See your GM dealer, if the TPMS sensors or
a wheel ever need replacement.
Notice:Using liquid sealants can damage the tire
valves and tire pressure monitor sensors in your
vehicle’s run-at tires. This damage would not
be covered by warranty. Do not use liquid sealants
in your vehicle’s run-at tires.
Ination - Tire Pressure
Tires need the correct amount of air pressure to operate
effectively.
Notice:Do not let anyone tell you that
under-ination or over-ination is all right. It is not.
If your tires do not have enough air (under-ination),
you can get the following:
Too much exing
Too much heat
Tire overloading
Premature or irregular wear
Poor handling
Reduced fuel economy
If your tires have too much air (over-ination), you
can get the following:
Unusual wear
Poor handling
Rough ride
Needless damage from road hazards
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TPM Sensor Identication Codes
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’s side front tire, passenger’s
side front tire, passenger’s side rear tire, and driver’s
side rear tire using a TPMS diagnostic tool. See
your GM dealer for service.
The TPMS sensors may also be matched to each
tire/wheel position by increasing or decreasing the tire’s
air pressure. If using this method to match TPMS
sensors, the complete procedure outlined below must
be performed within 15 minutes of the vehicle being
stationary.
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. A single
horn chirp will sound, indicating that the TPMS
is ready, and the sensor matching process
can begin.
5. Start with the driver’s 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. To decrease the tire’s air-pressure use the
pointed end of the valve cap, a pencil-style air
pressure gauge, or a key.
7. Proceed to the passenger’s side front tire, and
repeat the procedure in Step 6.
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8. Proceed to the passenger’s side rear tire, and
repeat the procedure in Step 6.
9. Proceed to the driver’s side rear tire, and repeat the
procedure in Step 6.
10. After hearing the conrming single horn chirp for the
driver’s 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.
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.
The spare tire does not have a TPMS sensor. If you
replace one of the road tires with the spare, the
SERVICE TIRE MONITOR message will be displayed
on the DIC screen. This message should go off
once you re-install the road tire containing the TPM
sensor. The SERVICE TIRE MONITOR message is also
displayed when the TPMS system is malfunctioning.
One or more missing or inoperable TPMS sensors will
cause the SERVICE TIRE MONITOR message to
be displayed. See your GM dealer for service.Federal Communications Commission
(FCC) and Industry and Science
Canada
This device complies with Part 15 of the FCC Rules.
Operation is subject to the following two conditions:
1. This device may not cause interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation.
This device complies with RSS-210 of Industry Canada.
Operation is subject to the following two conditions:
1. This device may not cause interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
Changes or modications to this system by other than
an authorized service facility could void authorization to
use this equipment.
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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.
Treadwear
The treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions on a specied government test course.
For example, a tire graded 150 would wear one and
a half (1.5) 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 signicantly 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 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.
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Lifting From the Rear
The rear lifting points can be accessed from either side
of your vehicle, in front of the rear tires.
1. Locate the rear lifting points using the diagram
above. The rear lifting location is about 7 inches
(17 cm) from the front edge of the rear wheel well.
2. Be sure to place a block or pad between the jack
and the vehicle.
3. Lift the vehicle with the jack, making sure the jack
is centered on the rear lifting point.
SeeDoing Your Own Service Work on page 5-4.
If a Tire Goes Flat
It is unusual for a tire to blowout while you are driving,
especially if you maintain your tires properly. See
Tires on page 5-56. 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 at tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel rmly.
Steer to maintain lane position, and then gently brake to
a stop well out of the traffic lane.
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.
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SeeRun-Flat Tires (STS-V) on page 5-63andTire
Pressure Monitor System on page 5-66, for additional
information.
{CAUTION:
Special tools and procedures are required to
service a run-at tire. If these special tools
and procedures are not used you or others
could be injured and your vehicle could be
damaged. Always be sure the proper tools
and procedures, as described in the service
manual, are used.
To order a service manual seeService Publications
Ordering Information on page 7-14.
Changing a Flat Tire (STS Only)
If you have an STS-V model, there is no spare tire and
no tire changing equipment. Your vehicle is equipped
with run-at tires. SeeRun-Flat Tires (STS-V) on
page 5-63for more information. If you have an STS
model, follow the directions for changing a at tire in
this section.
If a tire goes at, avoid further tire and wheel damage
by driving slowly to a level place. Turn on your vehicle’s
hazard warning ashers. SeeHazard Warning Flashers
on page 3-6for more information.
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