2006 CADILLAC DTS 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.
Notice:To make sure your headlamps are aimed
properly, read all the instructions before beginning.
Failure to follow these instructions could cause
damage to headlamp parts.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.
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Bulb Replacement
It is recommended that all bulbs be replaced by
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 has HID headlamps. After your vehicle’s
HID headlamp bulb has been replaced, you may notice
that the beam is a slightly different shade than it was
originally. This is normal.
Windshield Wiper Blade
Replacement
Windshield wiper blades should be inspected for wear
or cracking. SeeScheduled Maintenance on page 6-4
for more information on wiper blade inspection.
Replacement blades come in different types and are
removed in different ways. Here’s how to remove
the wiper blade:
1. Turn the engine off.
2. Lift the windshield wiper arm and blade away from
the windshield.
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A. Correct Installation
B. Incorrect Installation
For the proper type and size windshield wiper blades,
seeNormal Maintenance Replacement Parts on
page 6-13.
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.
{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 4-31.
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 5-56
for ination pressure adjustment for high
speed driving.
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Tire Sidewall Labeling
Useful information about a tire is molded into its 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.
(B) TPC Spec (Tire Performance Criteria
Specication):Original equipment tires designed to
GM’s specic tire performance criteria have a TPCspecication code molded onto the sidewall. GM’s TPC
specications meet or exceed all federal safety
guidelines.
(C) DOT (Department of Transportation):The
Department of Transportation (DOT) code indicates that
the tire is in compliance with the U.S. Department of
Transportation Motor Vehicle Safety Standards.
(D) Tire Identication Number (TIN):The letters
and numbers following the DOT code are 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.
(E) Tire Ply Material:The type of cord and number of
plies in the sidewall and under the tread.
(F) Uniform Tire Quality Grading (UTQG):Tire
manufacturers are required to grade tires based on
three performance factors: treadwear, traction and
temperature resistance. For more information see
Uniform Tire Quality Grading on page 5-67.
(G) Maximum Cold Ination Load Limit:Maximum
load that can be carried and the maximum pressure
needed to support that load. For information on
recommended tire pressure seeInation - Tire Pressure
on page 5-56andLoading Your Vehicle on page 4-31. Passenger Car 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. SeeSpare Tire on page 5-82
andIf a Tire Goes Flat on page 5-71.
(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 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. SeeInation - Tire
Pressure on page 5-56andLoading Your Vehicle on
page 4-31.
(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 5-56andSpare
Tire on page 5-82.
(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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(A) Tire Size:The tire size code 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.
(B) TPC Spec (Tire Performance Criteria
Specication):Original equipment tires designed to
GM’s specic tire performance criteria have a TPCspecication code molded onto the sidewall. GM’s TPC
specications meet or exceed all federal safety
guidelines.
(C) Dual Tire Maximum Load:Maximum load that can
be carried and the maximum pressure needed to
support that load when used in a dual conguration.
(D) DOT (Department of Transportation):The
Department of Transportation (DOT) code indicates that
the tire is in compliance with the U.S. Department of
Transportation Motor Vehicle Safety Standards.
(E) Tire Identication Number (TIN):The letters and
numbers following DOT code are 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.
(F) Tire Ply Material:The type of cord and number of
plies in the sidewall and under the tread.
(G) Single Tire Maximum Load:Maximum load that
can be carried and the maximum pressure needed
to support that load when used as a single. For
information on recommended tire pressure see
Ination - Tire Pressure on page 5-56. Light Truck Tire Example
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Tire Size
The following illustration shows an example of a tire size.
(A) 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.
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.
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Resetting the TPMS Sensor
Identication Codes
Each TPMS sensor has a unique identication code.
Any time you replace one or more of the TPMS sensors,
rotate the vehicle’s tires, or install a full-size spare
that has a TPMS sensor, the sensor’s identication
codes will need to be matched to the new tire/wheel
position. Each tire/wheel position is matched to
the TPMS sensor 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. When increasing the tire’s air pressure,
do not exceed the maximum tire pressure indicated on
the tire’s sidewall.
You will have two minutes to match the rst tire/wheel
position, and ve minutes overall, to match all
four tire/wheel positions. If it takes longer than
two minutes, to match the rst tire and wheel, or
more than ve minutes to match all four tire and wheel
positions the matching process stops and you will
need to start over.The TPMS matching process is outlined below:
1. Set the parking brake.
2. Turn the ignition switch to RUN with the engine off.
3. Press the Driver Information Center (DIC) vehicle
information button until the RELEARN TIRE
POSITIONS displays.
4. Press the set/reset button to allow the system to
learn the tire positions. The horn will sound twice
to indicate that the TPMS is ready, and then
the message TIRE LEARNING ACTIVE will display.
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, 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 gage or a key.
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