2005 CADILLAC STS check engine

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

(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

Owner Checks and Services
These owner checks and services should be performed
at the intervals specied to help ensure the safety,
dependability and emission control performance of your
vehicle. Your GM Goodwrench
®dealer can assist
you with these checks and services.
Be sure any necessary repairs are completed at once.
Whenever any uids or lubricants are added to your
vehicle, make sure they are the proper ones, as shown
inRecommended Fluids and Lubricants on page 6-12.
At Each Fuel Fill
It is important to perform these underhood checks at
each fuel ll.
Engine Oil Level Check
Check the engine oil level and add the proper oil if
necessary. SeeEngine Oil on page 5-15for further
details.
Notice:It is important to check your oil regularly
and keep it at the proper level. Failure to keep your
engine oil at the proper level can cause damage
to your engine not covered by your warranty.
Engine Coolant Level Check
Check the engine coolant level and add
DEX-COOL®coolant mixture if necessary. SeeEngine
Coolant on page 5-22for further details.
Windshield Washer Fluid Level Check
Check the windshield washer uid level in the windshield
washer tank and add the proper uid if necessary.
At Least Once a Month
Tire Ination Check
Visually inspect your vehicle’s tires and make sure they
are inated to the correct pressures. Do not forget to
check the spare tire. SeeTires on page 5-53for further
details. Check to make sure the spare tire is stored
securely. SeeChanging a Flat Tire on page 5-74.
Tire Wear Inspection
Tire rotation is recommended if your vehicle has the
same size tires at all four wheel positions and may
be required for high mileage highway drivers prior to
the Engine Oil Life System service notication. Check
the tires for wear and, if necessary, rotate the tires.
SeeTire Inspection and Rotation on page 5-65.
6-9

At Least Once a Year
Starter Switch Check
{CAUTION:
When you are doing this inspection, the
vehicle could move suddenly. If the vehicle
moves, you or others could be injured.
1. Before you start, be sure you have enough room
around the vehicle.
2. Firmly apply both the parking brake and the regular
brake. SeeParking Brake on page 2-29.
Do not use the accelerator pedal, and be ready to
turn off the engine immediately if it starts.
3. Try to start the engine in each gear. The vehicle
should start only in PARK (P) or NEUTRAL (N).
If the vehicle starts in any other position, contact
your GM Goodwrench
®dealer for service.
Automatic Transmission Shift Lock
Control System Check
{CAUTION:
When you are doing this inspection, the
vehicle could move suddenly. If the vehicle
moves, you or others could be injured.
1. Before you start, be sure you have enough room
around the vehicle. It should be parked on a level
surface.
2. Firmly apply the parking brake. SeeParking Brake
on page 2-29.
Be ready to apply the regular brake immediately if
the vehicle begins to move.
3. With the engine off and without applying the regular
brake, try to move the shift lever out of PARK (P)
with normal effort. If the shift lever moves out
of PARK (P), contact your GM Goodwrench
®dealer
for service.
6-10

Parking Brake and Automatic
Transmission Park (P) Mechanism Check
{CAUTION:
When you are doing this check, your vehicle
could begin to move. You or others could be
injured and property could be damaged. Make
sure there is room in front of your vehicle in
case it begins to roll. Be ready to apply the
regular brake at once should the vehicle begin
to move.Park on a fairly steep hill, with the vehicle facing
downhill. Keeping your foot on the regular brake, set
the parking brake.
To check the parking brake’s holding ability:
With the engine running and transmission in
NEUTRAL (N), slowly remove foot pressure from
the regular brake pedal. Do this until the vehicle
is held by the parking brake only.
To check the PARK (P) mechanism’s holding ability:
With the engine running, shift to PARK (P). Then
release the parking brake followed by the regular
brake.
Contact your GM Goodwrench
®dealer if service is
required.
Underbody Flushing Service
At least every spring, use plain water to ush any
corrosive materials from the underbody. Take care to
clean thoroughly any areas where mud and other
debris can collect.
6-11

Some information may be stored during regular
operations to facilitate repair of detected malfunctions;
other information is stored only in a crash event by
computer systems, such as those commonly called event
data recorders (EDR).
In a crash event, computer systems, such as the Airbag
Sensing and Diagnostic Module (SDM) in your vehicle
may record information about the condition of the vehicle
and how it was operated, such as data related to engine
speed, brake application, throttle position, vehicle speed,
safety belt usage, airbag readiness, airbag performance,
and the severity of a collision. If your vehicle is equipped
with StabiliTrak
®, steering performance, including yaw
rate, steering wheel angle, and lateral acceleration, is
also recorded. This information has been used to improve
vehicle crash performance and may be used to improve
crash performance of future vehicles and driving safety.
Unlike the data recorders on many airplanes, these
on-board systems do not record sounds, such as
conversation of vehicle occupants.
To read this information, special equipment is needed
and access to the vehicle or the device that stores
the data is required. GM will not access information
about a crash event or share it with others other than:
with the consent of the vehicle owner or, if the
vehicle is leased, with the consent of the lessee,
in response to an official request of police or similar
government office,
as part of GM’s defense of litigation through the
discovery process, or
as required by law.
In addition, once GM collects or receives data, GM may:
use the data for GM research needs,
make it available for research where appropriate
condentiality is to be maintained and need is
shown, or
share summary data which is not tied to a specic
vehicle with non-GM organizations for research
purposes.
Others, such as law enforcement, may have access to
the special equipment that can read the information
if they have access to the vehicle or the device
that stores the data.
If your vehicle is equipped with OnStar
®, please check
the OnStar®subscription service agreement or
manual for information on its operations and data
collection.
7-9