2005 CADILLAC STS engine

Fuses Usage
V8 ECM V8 ECM, Evap Solenoid
ABS Anti-Lock Brake Controller
STR RLY Starter Relay
WASH
NOZ/AQSHeated Washer Nozzles, Air Quality
Sensor™
ODD COILSOdd Ignition Coils, Odd Fuel
Injectors
TCM IPCTransmission, Instrument Panel,
Engine Control
SPARE Spare
MAF Mass Air Flow Sensor
HIGH FAN Cooling Fan - High Speed
LOW FAN Cooling Fan - Low Speed
RT PARK Right Park Lamp, Right Taillamp
HORN Horn
LT HI BEAM Left Headlamp High Beam
LT LOW BEAM Left Headlamp Low Beam
RT LOW BEAM Right Headlamp Low Beam
RT HI BEAM Right Headlamp High Beam
HFV6 ECMHigh Feature V6 Engine Control
ModuleRelays Usage
HDLP WASH
RELAY
JUMPER -OPTHeadlamp Washer
STARTER
RELAY MINIStarter
SPARE Spare
FOG LAMP
RELAY MICROFog Lamps
CMP CLU
RELAY MICROA/C Compressor Clutch
BLOWER
RELAY MINIFront Blower Motor
POWERTRAIN
RELAY MICROEngine Controls
RUN/CRANK
RELAY MICROIgnition 1
LOW SPEED
FAN RELAY
MINICooling Fan Low Speed
ACCESSORY
RELAY MINIIgnition 3
PARK LAMP
RELAY MICROParking Lamps
5-98

Capacities and Specications
The following approximate capacities are given in English and metric conversions. SeeRecommended Fluids and
Lubricants on page 6-12for more information.
ApplicationCapacities
English Metric
Air Conditioning Refrigerant R134a 1.4 lbs 0.63 kg
Cooling System 13.0 qt 12.3 L
Engine Oil with Filter
3.6L V6 6.0 qt 5.7 L
4.6L V8 8.0 qt 7.6 L
Fuel Tank 17.5 gal 66.3 L
Transmission 15.0 qt 14.2 L
Wheel Nut Torque 100 ft lb 140Y
All capacities are approximate. When adding, be sure to ll to the approximate level as recommended in this
manual. Recheck the uid level after lling.
Engine Specications
Engine VIN Code Transmission Spark Plug Gap
3.6L HFV6 7 Automatic 0.044 inches (1.1 mm)
4.6L DOHC V8 A Automatic 0.040 inches (1.0 mm)
5-106

Maintenance Schedule
Introduction
Important: Keep engine oil at the proper level and
change as recommended.
Have you purchased the GM Protection Plan? The Plan
supplements your new vehicle warranties. See your
Warranty and Owner Assistance booklet or your dealer
for details.
Maintenance Requirements
Notice:Maintenance intervals, checks, inspections,
replacement parts, and recommended uids and
lubricants as prescribed in this manual are necessary
to keep your vehicle in good working condition.
Any damage caused by failure to follow scheduled
maintenance may not be covered by warranty.
Your Vehicle and the Environment
Proper vehicle maintenance not only helps to keep your
vehicle in good working condition, but also helps the
environment. All recommended maintenance is
important. Improper vehicle maintenance can even
affect the quality of the air we breathe. Improper uid
levels or the wrong tire ination can increase the level of
emissions from your vehicle. To help protect our
environment, and to keep your vehicle in good condition,
be sure to maintain your vehicle properly.
Using the Maintenance Schedule
We at General Motors want to help you keep your vehicle
in good working condition. But we do not know exactly
how you will drive it. You may drive very short distances
only a few times a week. Or you may drive long distances
all the time in very hot, dusty weather. You may use your
vehicle in making deliveries. Or you may drive it to work,
to do errands or in many other ways.
Because of all the different ways people use their
vehicles, maintenance needs vary. You may need more
frequent checks and replacements. So please read
the following and note how you drive. If you have any
questions on how to keep your vehicle in good condition,
see your GM Goodwrench
®dealer.
6-2

Scheduled Maintenance
When the CHANGE ENGINE OIL SOON message in
the Driver Information Center (DIC) comes on, it means
that service is required for your vehicle. Have your
vehicle serviced as soon as possible within the next
600 miles (1 000 km). It is possible that, if you are
driving under the best conditions, the engine oil life
system may not indicate that vehicle service is
necessary for over a year. However, your engine oil
and lter must be changed at least once a year and
at this time the system must be reset. Your GM
Goodwrench
®dealer has GM-trained service technicians
who will perform this work using genuine GM parts
and reset the system.
If the engine oil life system is ever reset accidentally,
you must service your vehicle within 3,000 miles
(5 000 km) since your last service. Remember to reset
the oil life system whenever the oil is changed. See
Engine Oil Life System on page 5-18for information on
the Engine Oil Life System and resetting the system.When the CHANGE ENGINE OIL SOON message
appears, certain services, checks, and inspections are
required. Required services are described in the
following for “MaintenanceI” and “MaintenanceII.”
Generally, it is recommended that your rst service be
MaintenanceI, your second service be MaintenanceII,
and that you alternate MaintenanceIand MaintenanceII
thereafter. However, in some cases, MaintenanceII
may be required more often.
MaintenanceI— Use MaintenanceIif the CHANGE
ENGINE OIL SOON message comes on within
10 months since the vehicle was purchased or
MaintenanceIIwas performed.
MaintenanceII— Use MaintenanceIIif the previous
service performed was MaintenanceI. Always use
MaintenanceIIwhenever the message comes on
10 months or more since the last service or if the
message has not come on at all for one year.
6-4

Scheduled Maintenance
Service MaintenanceIMaintenanceII
Change engine oil and lter. SeeEngine Oil on page 5-15. Reset oil life system.
SeeEngine Oil Life System on page 5-18.An Emission Control Service.••
Visually check for any leaks or damage.See footnote (k).••
Inspect engine air cleaner lter. If necessary, replace lter. SeeEngine Air
Cleaner/Filter on page 5-20.See footnote (m).•
Check tires for ination pressures and wear. SeeTires on page 5-53. If tire
rotation is recommended for your vehicle, rotate tires. SeeTire Inspection and
Rotation on page 5-65and “Tire Wear Inspection” inAt Least Once a Month
on page 6-9.••
Inspect brake system.See footnote (a).••
Check engine coolant and windshield washer uid levels and add uid as
needed.••
Perform any needed additional services. See “Additional Required Services”
in this section.••
Inspect suspension and steering components.See footnote (b).•
Inspect engine cooling system.See footnote (c).•
Inspect wiper blades.See footnote (d).•
Inspect restraint system components.See footnote (e).•
Lubricate body components.See footnote (f).•
Check transmission uid level and add uid as needed.•
Replace passenger compartment air lter.See footnote (g).•
6-5

Additional Required Services
The following services should be performed at the rst maintenance service (IorII) after the indicated miles (kilometers)
shown for each item.
Additional Required Services
Service and Miles (Kilometers)25,000
(41 500)50,000
(83 000)75,000
(125 000)100,000
(166 000)125,000
(207 500)150,000
(240 000)
Inspect fuel system for damage
or leaks.• •••••
Inspect exhaust system for loose or
damaged components.• •••••
Replace engine air cleaner lter. See
Engine Air Cleaner/Filter on page 5-20.••
Change automatic transmission
uid and lter (severe service only).
See footnote (h).•••
For all-wheel-drive vehicles used for
trailer towing: Change transfer case
uid.•••
Throttle body service.An Emission
Control Service. See footnotes † and (l).• •••••
Replace spark plugs.An Emission
Control Service.•
6-6

Additional Required Services (cont’d)
Service and Miles (Kilometers)25,000
(41 500)50,000
(83 000)75,000
(125 000)100,000
(166 000)125,000
(207 500)150,000
(240 000)
Engine cooling system service
(or every ve years, whichever occurs
rst).An Emission Control Service.
See footnote (j).•
Inspect engine accessory drive belt.
An Emission Control Service.•
Maintenance Footnotes
†The U.S. Environmental Protection Agency or the
California Air Resources Board has determined that the
failure to perform this maintenance item will not nullify
the emission warranty or limit recall liability prior to
the completion of the vehicle’s useful life. We, however,
urge that all recommended maintenance services be
performed at the indicated intervals and the
maintenance be recorded.
(a)Visually inspect brake lines and hoses for proper
hook-up, binding, leaks, cracks, chang, etc. Inspect
disc brake pads for wear and rotors for surface
condition. Inspect other brake parts, including calipers,
parking brake, etc.(b)Visually inspect front and rear suspension and
steering system for damaged, loose, or missing parts or
signs of wear. Inspect power steering lines and hoses
for proper hook-up, binding, leaks, cracks, chang, etc.
(c)Visually inspect hoses and have them replaced if
they are cracked, swollen, or deteriorated. Inspect
all pipes, ttings, and clamps; replace with genuine
GM parts as needed. To help ensure proper operation,
a pressure test of the cooling system and pressure
cap and cleaning the outside of the radiator and
air conditioning condenser is recommended at least
once a year.
6-7

(d)Visually inspect wiper blades for wear or cracking.
Replace blade inserts that appear worn or damaged
or that streak or miss areas of the windshield.
(e)Make sure the safety belt reminder light and all your
belts, buckles, latch plates, retractors, and anchorages
are working properly. Look for any other loose or
damaged safety belt system parts. If you see anything
that might keep a safety belt system from doing its
job, have it repaired. Have any torn or frayed safety belts
replaced. Also look for any opened or broken airbag
coverings, and have them repaired or replaced.
The airbag system does not need regular maintenance.
(f)Lubricate all key lock cylinders. Lubricate all
hinges and latches, including those for the hood, rear
compartment, glove box door, and console door.
More frequent lubrication may be required when
exposed to a corrosive environment. Applying silicone
grease on weatherstrips with a clean cloth will make
them last longer, seal better, and not stick or squeak.
(g)If you drive regularly under dusty conditions, the lter
may require replacement more often.(h)Change automatic transmission uid and lter if the
vehicle is mainly driven under one or more of these
conditions:
In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as limousine service.
Uses such as high performance operation.
If you do not use your vehicle under any of these
conditions, the uid and lter do not require change.
(j)Drain, ush, and rell cooling system. This service
can be complex; you should have your dealer perform
this service. See Engine Coolant on page 5-22 for
what to use. Inspect hoses. Clean radiator, condenser,
pressure cap, and ller neck. Pressure test the
cooling system and pressure cap.
(k)A uid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired
and the uid level checked. Add uid if needed.
(l)Inspect throttle body bore and valve plates for
deposits. Open the throttle valve and inspect all
surfaces. Clean as required.
(m)If you drive regularly under dusty conditions, inspect
the lter at each engine oil change.
6-8