2005 CADILLAC STS light

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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To adjust the vertical aim do the following:
1. Open the hood. SeeHood Release on page 5-11.
2. Find the aim dot on the lens of the low-beam
headlamp.
3. Measure the distance from the ground to the aim dot
on the low-beam headlamp. Record the distance.
4. At the wall or other at surface, measure from the
ground upward the recorded distance from Step 2
and mark it.
5. Draw or tape a horizontal line the width of the
vehicle at the wall or other at surface where it
was marked it Step 4.Notice:Do not cover a headlamp to improve beam
cut-off when aiming. Covering a headlamp may
cause excessive heat build-up which may cause
damage to the headlamp.
6. Turn on the low-beam headlamps and place a
piece of cardboard or equivalent in front of the
headlamp not being aimed. This should allow only
the beam of light from the headlamp being
aimed to be seen on the at surface.
7. Locate the vertical headlamp aiming screws, which
are under the hood near each headlamp assembly.
The adjustment screw can be turned witha6mmhex
socket.
Passenger’s Side Shown
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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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Sidemarker Lamps
To replace a sidemarker lamp bulb, do the following:
1. Locate the rear sidemarker lamp assembly
under the rear bumper.
2. Turn the socket
counterclockwise and
then pull it straight
out from the
sidemarker lamp
assembly.
3. Pull the old bulb straight out and reinstall
the new bulb.
4. Reverse Step 2 to reinstall the socket.
Back-Up Lamps
To replace a back-up lamp bulb, do the following:
1. Open the trunk. SeeTrunk on page 2-14for more
information.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. Reverse the steps to reinstall.
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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.
Bias Ply Tire:A pneumatic tire in which the plies are
laid at alternate angles less than 90 degrees to the
centerline of the tread.
Cold Ination 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. SeeInation - Tire Pressure on page 5-60.Curb Weight:This means 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
Identication Number (TIN), an alphanumeric designator
which can also identify the tire manufacturer, production
plant, brand and date of production.
GVWR:Gross Vehicle Weight Rating, seeLoading
Your Vehicle on page 4-30.
GAWR FRT:Gross Axle Weight Rating for the front
axle, seeLoading Your Vehicle on page 4-30.
GAWR RR:Gross Axle Weight Rating for the rear axle,
seeLoading Your Vehicle on page 4-30.
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.
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Load Index:An assigned number ranging from 1 to
279 that corresponds to the load carrying capacity
of a tire.
Maximum Ination Pressure:The maximum air
pressure to which a cold tire may be inated. The
maximum air pressure is molded onto the sidewall.
Maximum Load Rating:The load rating for a tire at the
maximum permissible ination 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).
SeeLoading Your Vehicle on page 4-30.
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 Ination Pressure:Vehicle
manufacturer’s recommended tire ination pressure and
shown on the tire placard. SeeInation - Tire Pressure
on page 5-60andLoading Your Vehicle on page 4-30.
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 5-67.
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If a low tire pressure condition is detected, the TPM
system will display the CHECK TIRE PRESSURE
warning message on the Driver Information Center (DIC)
and, at the same time, illuminate the low tire pressure
warning symbol, on the instrument panel cluster.
When the tire pressure
monitoring system warning
light is lit, one or more
of your tires is signicantly
under-inated.
You should stop and check your tires as soon as
possible, and inate them to the proper pressure as
indicated on the vehicle’s tire information placard.
Driving on a signicantly under-inated tire causes the
tire to overheat and can lead to tire failure.
Under-ination also reduces fuel efficiency and tire tread
life, and may affect the vehicle’s handling and stopping
ability. Each tire, including the spare, should be
checked monthly when cold and set to the
recommended ination pressure as specied in the
vehicle placard and owner’s manual.The Tire and Loading Information Label (your vehicle’s
tire information placard) shows the size of your vehicle’s
original tires and the recommended cold ination
pressure for your vehicle’s tire. SeeInation - Tire
Pressure on page 5-60. For the location of the tire and
loading information label, seeLoading Your Vehicle on
page 4-30.
Your vehicle’s TPM system can alert you about a low
tire pressure condition but it does not replace normal tire
maintenance. SeeTire Inspection and Rotation on
page 5-65andTires on page 5-53.
Notice:Do not use a tire sealant if your vehicle is
equipped with Tire Pressure Monitors. The liquid
sealant can damage the tire pressure monitor
sensors.
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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, 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
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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