2008 CADILLAC DTS fuel

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 a crash, 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/retailer for service if the headlamps need to
be re-aimed. It is possible however, to re-aim the
headlamps as described.
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 placed so the headlamps are 25 ft. (7.6 m) from
a light colored wall.
Have all four tires on a level surface which is level
all the way to the wall.
Be placed so it is perpendicular to the wall.
Not have any snow, ice, or mud on it.
Be fully assembled and all other work stopped while
headlamp aiming is being performed.
Be normally loaded with a full tank of fuel and one
person or 160 lbs (75 kg) sitting on the driver seat.
Have all tires properly inated.
Have 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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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 Tire 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. SeeInflation - Tire Pressure on
page 5-60.
Curb Weight
: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 the Vehicle on page 4-20.
GAWR FRT
:Gross Axle Weight Rating for the
front axle. SeeLoading the Vehicle on page 4-20.
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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 hazardsA Tire and Loading Information label is attached
to the vehicle’s center pillar. This label lists your
vehicle’s original equipment tires and shows the
correct ination pressures for your tires when they
are cold. The recommended cold tire ination
pressure, shown on the label, is the minimum
amount of air pressure needed to support your
vehicle’s maximum load carrying capacity.
For additional information regarding how much
weight your vehicle can carry, and an example
of the Tire and Loading Information label, see
Loading the Vehicle on page 4-20. How you load
your vehicle affects the vehicle handling and ride
comfort, never load your vehicle with more weight
than it was designed to carry.
When to Check
Check your tires once a month or more. Do not
forget to check the spare tire. If your vehicle has a
compact spare tire, it should be at 60 psi (420 kPa).
For additional information seeSpare Tire on
page 5-89.
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Tire Pressure Monitor System
The Tire Pressure Monitor System (TPMS) uses radio
and sensor technology to check tire pressure levels.
The TPMS sensors monitor the air pressure in
your vehicle’s tires and transmit tire pressure readings
to a receiver located in the vehicle.
Each tire, including the spare (if provided), should be
checked monthly when cold and inated to the ination
pressure recommended by the vehicle manufacturer
on the vehicle placard or tire ination pressure label.
(If your vehicle has tires of a different size than the
size indicated on the vehicle placard or tire ination
pressure label, you should determine the proper
tire ination pressure for those tires.)
As an added safety feature, your vehicle has been
equipped with a tire pressure monitoring system (TPMS)
that illuminates a low tire pressure telltale when one
or more of your tires is signicantly under-inated.
Accordingly, when the low tire pressure telltale
illuminates, you should stop and check your tires
as soon as possible, and inate them to the proper
pressure. 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.Please note that the TPMS is not a substitute for proper
tire maintenance, and it is the driver’s responsibility to
maintain correct tire pressure, even if under-ination
has not reached the level to trigger illumination of
the TPMS low tire pressure telltale.
Your vehicle has also been equipped with a TPMS
malfunction indicator to indicate when the system is not
operating properly. The TPMS malfunction indicator is
combined with the low tire pressure telltale. When the
system detects a malfunction, the telltale will ash
for approximately one minute and then remain
continuously illuminated. This sequence will continue
upon subsequent vehicle start-ups as long as the
malfunction exists.
When the malfunction indicator is illuminated, the
system may not be able to detect or signal low tire
pressure as intended. TPMS malfunctions may occur
for a variety of reasons, including the installation of
replacement or alternate tires or wheels on the vehicle
that prevent the TPMS from functioning properly. Always
check the TPMS malfunction telltale after replacing one
or more tires or wheels on your vehicle to ensure that
the replacement or alternate tires and wheels allow the
TPMS to continue to function properly.
SeeTire Pressure Monitor Operation on page 5-64for
additional information.
5-63

Tires
To clean the tires, use a stiff brush with tire cleaner.
Notice:Using petroleum-based tire dressing
products on your vehicle may damage the paint
nish and/or tires. When applying a tire dressing,
always wipe off any overspray from all painted
surfaces on your vehicle.
Sheet Metal Damage
If the vehicle is damaged and requires sheet metal
repair or replacement, make sure the body repair
shop applies anti-corrosion material to parts repaired
or replaced to restore corrosion protection.
Original manufacturer replacement parts will provide
the corrosion protection while maintaining the vehicle
warranty.
Finish Damage
Any stone chips, fractures or deep scratches in the
nish should be repaired right away. Bare metal
will corrode quickly and may develop into major
repair expense.
Minor chips and scratches can be repaired with touch-up
materials available from your dealer/retailer. Larger
areas of nish damage can be corrected in your
dealer’s/retailer’s body and paint shop.
Underbody Maintenance
Chemicals used for ice and snow removal and dust
control can collect on the underbody. If these are not
removed, corrosion and rust can develop on the
underbody parts such as fuel lines, frame, oor pan,
and exhaust system even though they have corrosion
protection.
At least every spring, ush these materials from the
underbody with plain water. Clean any areas where mud
and debris can collect. Dirt packed in close areas of the
frame should be loosened before being ushed. Your
dealer/retailer or an underbody car washing system can
do this for you.
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Fuses Usage
1Engine Control Module (ECM),
Crank
2 Fuel Injectors Odd
3 Fuel Injectors EvenFuses Usage
4 Air Conditioning Clutch
5 Air Injection Reactor (AIR) Solenoid
6 Oxygen Sensor
5-102

Fuses Usage
1 Fuel Pump
2 Left Park Lamp
3 Run 3 - Rear BlowerFuses Usage
4 Right Park Lamp
5Engine Control Module (ECM)/
Transmission Control Module (TCM)
6 Memory Module
5-106

Fuses Usage
42 OnStar
®Module
43 Body Modules
44 Radio
45 Door Unlatch (optional)
46 Rear Defogger (J-Case)
47Electronic Leveling Control
Compressor (J-Case)
48 Blower (J-Case) (optional)
49 Blower (J-Case) (optional)
Resistor Usage
50 Terminating Resistor
Relays Usage
51 Front Blower (optional)
52 Rear Defogger
53Electronic Leveling Control
Compressor
58 Park Lamps
59 Fuel Pump
60 License Plate Lamp (optional)
Relays Usage
61 Right Park Lamp (optional)
62 Unlock
63 Lock
64 Run
65Daytime Running Lamps (DRL)
(optional)
66 Door Unlatch (optional)
67 Trunk Release
68 Stoplamp (optional)
69 Overhead Lamps (optional)
70 Retained Accessory Power (RAP)
Circuit
BreakersUsage
54 Right Front Seat
55 Left Front Power Seat
56 Power Windows
57 Power Tilt Steering Wheel
5-108