2006 CADILLAC STS check oil

Engine Oil Life System
When to Change Engine Oil
Your vehicle has a computer system that lets you
know when to change the engine oil and lter. This is
based on engine revolutions and engine temperature,
and not on mileage. Based on driving conditions,
the mileage at which an oil change will be indicated
can vary considerably. For the oil life system to
work properly, you must reset the system every time
the oil is changed.
Notice:If your vehicle is an STS-V model, the engine
uses a special oil lter. The use of any other engine
oil lter could lead to lter failure and result in severe
engine damage. Damage caused by use of the wrong
engine oil lter would not be covered by your new
vehicle warranty.When the system has calculated that oil life has been
diminished, it will indicate that an oil change is necessary.
A CHANGE ENGINE OIL SOON message in the DIC
will come on. SeeDIC Warnings and Messages on
page 3-79. Change your oil 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 oil life system
may not indicate that an oil change 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 dealer has GM-trained service
people who will perform this work using genuine
GM parts and reset the system. It is also important to
check your oil regularly and keep it at the proper level.
If the system is ever reset accidentally, you must change
your oil at 3,000 miles (5 000 km) since your last oil
change. Remember to reset the oil life system whenever
the oil is changed.
5-22

Automatic Transmission Fluid
How to Check Automatic
Transmission Fluid
It is not necessary to check the transmission uid level.
A transmission uid leak is the only reason for uid
loss. If a leak occurs, take the vehicle to the dealership
service department and have it repaired as soon as
possible.
There is a special procedure for checking and changing
the transmission uid. Because this procedure is
difficult, you should have this done at the dealership
service department. Contact your dealer for additional
information or the procedure can be found in the service
manual. To purchase a service manual, seeService
Publications Ordering Information on page 7-14.
Notice:Use of the incorrect automatic transmission
uid may damage your vehicle, and the damages
may not be covered by your warranty. Always
use the automatic transmission uid listed in
Recommended Fluids and Lubricants on page 6-12.
Change the uid and lter at the intervals listed in
Additional Required Services on page 6-6, and be sure
to use the uid listed inRecommended Fluids and
Lubricants on page 6-12.
Engine Coolant
The cooling system in your vehicle is lled with
DEX-COOL®engine coolant. This coolant is designed
to remain in your vehicle for ve years or 150,000 miles
(240 000 km), whichever occurs rst, if you add only
DEX-COOL
®extended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem with
engine overheating, seeEngine Overheating on
page 5-30.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
Give freezing protection down to−34°F (−37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as they
should.
Notice:Using coolant other than DEX-COOL
®may
cause premature engine, heater core, or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at the rst maintenance
service after each 30,000 miles (50 000 km) or
24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
5-26

What to Use
Use a mixture of one-half clean, drinkable water and
one-half DEX-COOL®coolant which will not damage
aluminum parts. If you use this coolant mixture, you do
not need to add anything else.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle’s coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you would not get the overheat warning.
Your engine could catch re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.Notice:If you use an improper coolant mixture,
your engine could overheat and be badly damaged.
The repair cost would not be covered by your
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core, and
other parts.
If you have to add coolant more than once or twice a
year, have your dealer check your cooling system.
Notice:If you use extra inhibitors and/or additives
in your vehicle’s cooling system, you could
damage your vehicle. Use only the proper mixture
of the engine coolant listed in this manual for
the cooling system. SeeRecommended Fluids and
Lubricants on page 6-12for more information.
5-27

If No Steam Is Coming From
Your Engine
An overheat warning, along with a CHECK COOLANT
LEVEL message, can indicate a serious problem.
If you get an engine overheat warning with no CHECK
COOLANT LEVEL message, but see or hear no
steam, the problem may not be too serious. Sometimes
the engine can get a little too hot when you:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer.
If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. In heavy traffic, let the engine idle in NEUTRAL (N)
while stopped. If it is safe to do so, pull off the road,
shift to PARK (P) or NEUTRAL (N) and let the
engine idle.
2. Set the climate controls to the highest heat setting
and fan speed and open the windows, as
necessary.
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning does not come back on, you can drive
normally.If the warning continues and you have not stopped,
pull over, stop, and park your vehicle right away.
If there is still no sign of steam, you can idle the engine
for three minutes while you are parked. If you still have
the warning, turn off the engine and get everyone out of
the vehicle until it cools down. Also, see “Overheated
Engine Protection Operating Mode” later in this section.
You may decide not to lift the hood but to get service
help right away.
Overheated Engine Protection
Operating Mode
This operating mode allows your vehicle to be driven to
a safe place in an emergency. Should an overheated
engine condition exist, an overheat protection mode
which alternates ring groups of cylinders helps prevent
engine damage. In this mode, you will notice a loss
in power and engine performance. A low coolant and/or
engine overheat warning will indicate that an overheat
condition exists. Driving extended miles (km) and/or
towing a trailer in the overheat protection mode should
be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any repair.
The engine oil will be severely degraded. Repair the
cause of coolant loss and change the oil. SeeEngine
Oil on page 5-18.
5-31

How to Add Coolant to the Coolant
Surge Tank
If you have not found a problem yet, check to see if
coolant is visible in the surge tank. If coolant is visible
but the coolant level is not at the FULL COLD/FROID
line on the side of the coolant surge tank, add a
50/50 mixture of clean, drinkable water and DEX-COOL
®
coolant at the coolant surge tank, but be sure the
cooling system, including the coolant surge tank
pressure cap, is cool before you do it. SeeEngine
Coolant on page 5-26for more information.
{CAUTION:
Steam and scalding liquids from a hot cooling
system can blow out and burn you badly. They
are under pressure, and if you turn the coolant
surge tank pressure cap — even a little — they
can come out at high speed. Never turn the
cap when the cooling system, including the
coolant surge tank pressure cap, is hot. Wait
for the cooling system and coolant surge tank
pressure cap to cool if you ever have to turn
the pressure cap.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle’s coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you would not get the overheat warning.
Your engine could catch re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.
Notice:In cold weather, water can freeze and crack
the engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mixture.
5-34

How to Add Coolant to the
Intercooler System Fill Neck
(4.4L V8 STS-V Engine Only)
If you have not found a problem yet, turn the engine off
and allow it to cool down, then check to see if coolant is
visible within the horizontal tube section of the ll neck.
If coolant is not visible, add a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant to the ll neck.
Be sure the Intercooler System, including the Intercooler
System pressure cap, is cool before doing so. See
Engine Coolant on page 5-26for more information.
{CAUTION:
Turning the Intercooler System pressure cap
when the engine and intercooler are hot can
allow steam and scalding liquids to blow out
and burn you badly. Never turn the Intercooler
System pressure cap, even a little, when the
engine and intercooler are hot.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle’s coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you would not get the overheat warning.
Your engine could catch re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.
Notice:In cold weather, water can freeze and crack
the engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mixture.
5-37

Compact Spare Tire (STS Only)
Although the compact spare tire was fully inated
when the vehicle was new, it can lose air after a time.
Check the ination pressure regularly. It should be
60 psi (420 kPa).
After installing the compact spare on the vehicle, you
should stop as soon as possible and make sure the spare
tire is correctly inated. The compact spare is made to
perform well at speeds up to 65 mph (105 km/h) for
distances up to 3,000 miles (5 000 km), so you can nish
your trip and have the full-size tire repaired or replaced
where you want. You must calibrate the tire ination
monitor system after installing or removing the compact
spare. SeeTire Pressure Monitor System on page 5-66.
The system may not work correctly when the compact
spare is installed on the vehicle. Of course, it’s best to
replace the spare with a full-size tire as soon as you can.
The spare will last longer and be in good shape in case
you need it again.
Notice:When the compact spare is installed, do not
take your vehicle through an automatic car wash with
guide rails. The compact spare can get caught on the
rails. That can damage the tire and wheel, and maybe
other parts of your vehicle.
Do not use the compact spare on other vehicles.And do not mix the compact spare tire or wheel with
other wheels or tires. They will not t. Keep the
spare tire and its wheel together.
Notice:Tire chains will not t your compact spare.
Using them can damage your vehicle and can
damage the chains too. Do not use tire chains on
your compact spare.
Appearance Care
Cleaning the Inside of Your Vehicle
Your vehicle’s interior will continue to look its best if
it is cleaned often. Although not always visible, dust
and dirt can accumulate on your upholstery. Dirt
can damage carpet, fabric, leather, and plastic surfaces.
Regular vacuuming is recommended to remove
particles from your upholstery. It is important to keep
your upholstery from becoming and remaining heavily
soiled. Soils should be removed as quickly as possible.
Your vehicle’s interior may experience extremes of
heat that could cause stains to set rapidly.
Lighter colored interiors may require more frequent
cleaning. Use care because newspapers and garments
that transfer color to your home furnishings may also
transfer color to your vehicle’s interior.
5-94

The underhood fuse block is located in the front of the
engine compartment on the passenger’s side of the
vehicle. SeeEngine Compartment Overview on
page 5-12for more information on location, and removal
procedure for the front compartment underhood sights
shields.
To access the fuses, push in the tabs located on each
side of the fuse block cover. Then, lift the cover off.
Fuses Usage
BLOWER Blower Motor
R REAR Passenger’s Side Rear Fuse Block
I/P OUTLET Front Accessory Power Outlet
CCP Climate Control, Headlamp Leveling
PRE 02/CAM Oxygen Sensor, Camshaft Phasers
ENG W/H Engine Wiring Harness
R REAR Passenger’s Side Rear Fuse Block
WPR SW Wiper/Washer Switch
BODY W/H Body Wiring Harness
FOG LAMP Fog Lamps
OUTLET Rear Accessory Power Outlet
Fuses Usage
EVEN COILSEven Ignition Coils, Even Fuel
Injectors
L REAR Driver’s Side Rear Fuse Block
WPR MOD Wiper Module
POST 02 Oxygen Sensor
COMP CLTCH Air Conditioner Compressor Clutch
STARTER Starter Solenoid
ABS Anti-lock Brake Pump
L REAR Driver’s Side Rear Fuse Block
BODY W/H Body Wiring Harness
RAIN SSRRain Sensor, Headlamp Washer,
Tire Pressure Monitor
CCP Climate Control
SMT BM-OPT IntelliBeam™ Relay (If Equipped)
EXT LIGHTSLow Beam Relay, High Beam Relay,
Park Lamp Relay
VOLT CHECK Instrument Panel Module
5-107