2005 CADILLAC STS service

Headlamp Aiming
The vehicle has a visual optical headlamp aiming
system. The aim has been preset at the factory and
should need no further adjustment.
However, if the vehicle is damaged in an accident, the
headlamp aim may be affected and adjustment may
be necessary.
If oncoming vehicles ash their high beams at you, this
may also mean the vertical aim needs to be adjusted.
It is recommended that the vehicle is taken to your
dealer for service if the headlamps need to be re-aimed.
It is possible however, to re-aim the headlamps as
described in the following procedure.
The vehicle should be properly prepared as follows:
The vehicle should be placed so the headlamps are
25 ft. (7.6 m) from a light colored wall or other at
surface.
The vehicle must have all four tires on a level
surface which is level all the way to the wall or other
at surface.
The vehicle should be placed so it is perpendicular
to the wall or other at surface.
The vehicle should not have any snow, ice, or
mud on it.
The vehicle should be fully assembled and all other
work stopped while headlamp aiming is being
performed.
The vehicle should be normally loaded with a full
tank of fuel and one person or 160 lbs (75 kg)
sitting on the driver’s seat.
Tires should be properly inated.
The spare tire is in its original location in the
vehicle.
Headlamp aiming is done with the vehicle’s low-beam
headlamps. The high-beam headlamps will be correctly
aimed if the low-beam headlamps are aimed properly.
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8. Turn the vertical aiming screw until the headlamp
beam is aimed to the horizontal tape line. If you
turn it clockwise, it will raise the beam and if
you turn it counterclockwise, it will lower the beam.
The top edge of the cut-off should be positioned
at the bottom edge of the horizontal tape line.
9. Repeat Steps 7 and 8 for the opposite headlamp.
Bulb Replacement
For the proper type of replacement bulbs, see
Replacement Bulbs on page 5-51.
For any bulb changing procedure not listed in this
section, contact your dealer.
High Intensity Discharge (HID)
Lighting
{CAUTION:
The low beam high intensity discharge lighting
system operates at a very high voltage. If you
try to service any of the system components,
you could be seriously injured. Have your
dealer or a qualied technician service them.
Your vehicle may have HID headlamps and fog lamps.
After your vehicle’s HID headlamp or fog lamp bulb has
been replaced, you may notice that the beam is a slightly
different shade than it was originally. This is normal.
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Tires
Your new vehicle comes with high-quality tires made by
a leading tire manufacturer. If you ever have questions
about your tire warranty and where to obtain service,
see your GM Warranty booklet for details. For additional
information refer to the tire manufacturer’s booklet
included with your vehicle’s Owner’s Manual.{CAUTION:
Poorly maintained and improperly used
tires are dangerous.
Overloading your tires can cause
overheating as a result of too much
friction. You could have an air-out and a
serious accident. SeeLoading Your
Vehicle on page 4-30.
Underinated tires pose the same danger
as overloaded tires. The resulting accident
could cause serious injury. Check all tires
frequently to maintain the recommended
pressure. Tire pressure should be checked
when your tires are cold.
Overinated tires are more likely to be cut,
punctured, or broken by a sudden
impact — such as when you hit a pothole.
Keep tires at the recommended pressure.
Worn, old tires can cause accidents. If your
tread is badly worn, or if your tires have
been damaged, replace them.
SeeInflation - Tire Pressure on page 5-60for
ination pressure adjustment for high speed
driving.
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Winter Tires
If you expect to drive on snow or ice covered roads
often, you may want to get winter tires for your vehicle.
All season tires provide good overall performance on
most surfaces but they may not offer the traction
you would like or the same level of performance as
winter tires on snow or ice covered roads.
See your dealer for details regarding winter tire
availability and proper tire selection. Also, seeBuying
New Tires on page 5-68
If you choose to use winter tires:
Use tires of the same brand and tread type on all
four wheel positions.
Use only radial ply tires of the same size, load
range, and speed rating as the original equipment
tires.
Winter tires with the same speed rating as your original
equipment tires may not be available for H, V, W
and ZR speed rated tires. If you choose winter tires with
a lower speed rating, never exceed the tire’s maximum
speed capability.
Tire Sidewall Labelling
Useful information about a tire is molded into its
sidewall. The examples below show a typical passenger
vehicle tire and a compact spare tire sidewall.
(A) Tire Size:The tire size is a combination of letters
and numbers used to dene a particular tire’s width,
height, aspect ratio, construction type and service
description. See the “Tire Size” illustration later in this
section for more detail.Passenger (P-Metric) Tire Example
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(A) Temporary Use Only:The compact spare tire or
temporary use tire has a tread life of approximately
3,000 miles (5 000 km) and should not be driven
at speeds over 65 mph (105 km/h). The compact spare
tire is for emergency use when a regular road tire
has lost air and gone at. If your vehicle has a compact
spare tire, seeCompact Spare Tire on page 5-84
andIf a Tire Goes Flat on page 5-74.(B) Tire Ply Material:The type of cord and number of
plies in the sidewall and under the tread.
(C) Tire Identication Number (TIN):The letters
and numbers following the DOT (Department of
Transportation) code is the Tire Identication
Number (TIN). The TIN shows the manufacturer and
plant code, tire size, and date the tire was manufactured.
The TIN is molded onto both sides of the tire, although
only one side may have the date of manufacture.
(D) Maximum Cold Ination Load Limit:Maximum
load that can be carried and the maximum pressure
needed to support that load.
(E) Tire Ination:The temporary use tire or compact
spare tire should be inated to 60 psi (420 kPa).
For more information on tire pressure and ination see
Ination - Tire Pressure on page 5-60.
(F) Tire Size:A combination of letters and numbers
dene a tire’s width, height, aspect ratio, construction
type and service description. The letter T as the
rst character in the tire size means the tire is for
temporary use only.
(G) TPC Spec (Tire Performance Criteria
Specication):Original equipment tires designed to
GM’s specic tire performance criteria have a TPC
specication code molded onto the sidewall. GM’s TPC
specications meet or exceed all federal safety
guidelines. Compact Spare Tire Example
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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.
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TPM Sensor Identication Codes
Each TPM sensor has a unique identication code. Any
time you replace one or more of the TPM 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: left front (LF), right front (RF), right
rear (RR), and left rear (LR) using a TPM diagnostic
tool. See your GM dealer for service.
The TPM 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 TPM
sensors, the complete procedure outlined below must
be performed after the vehicle has been driven at
least 20 mph (32 km/h), for at least 10 seconds, and
within 15 minutes from when the vehicle is 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 OFF/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 TPM
system is ready, and the sensor matching process
can begin.
5. Start with the left (driver’s side) front tire.
6. Remove the valve cap from the valve stem.
Activate the TPM 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, 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 right (passenger’s side) front tire,
and repeat the procedure in Step 6.
8. Proceed to the right (passenger’s side) rear tire,
and repeat the procedure in Step 6.
9. Proceed to the left (driver’s side) rear tire, and
repeat the procedure in Step 6.
10. After hearing the conrming double horn chirp, for
the left rear tire, exit the matching process by
pressing the push-button ignition switch to
OFF/ACC.
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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 TPM 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 TPM system is malfunctioning.
One or more missing or inoperable TPM sensors will
cause the SERVICE TIRE MONITOR message to
be displayed. See your GM dealer for service.
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.
Tire Inspection and Rotation
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.
P235/50R18 size tires on the front wheels and
P255/45R18 size tires on the rear wheels.
Different tire sizes front to rear should not be rotated.
Each tire and wheel should be used only in the position
it is in.
Tire rotation is recommended if your 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)
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