service CADILLAC STS 2006 1.G Service Manual

Magnetic Ride Control
Your vehicle may have Magnetic Ride Control that
automatically adjusts the ride of your vehicle. Automatic
ride control is achieved through a computer used to
control and monitor the suspension system. The
controller receives input from various sensors to
determine the proper system response. If the controller
detects a problem within the system, the DIC will
display a SERVICE SUSPENSION SYS message.
SeeDIC Warnings and Messages on page 3-79for
more information. See your dealer for service.
Limited-Slip Rear Axle
Your limited-slip rear axle can give you additional traction
on snow, mud, ice, sand or gravel. It works like a
standard axle most of the time, but when one of the rear
wheels has no traction and the other does, this feature
will allow the wheel with traction to move the vehicle.
StabiliTrak®System
Your vehicle is equipped with a vehicle stability
enhancement system called StabiliTrak®.Itisan
advanced computer controlled system that assists
you with directional control of the vehicle in difficult
driving conditions.
StabiliTrak
®activates when the computer senses a
discrepancy between your intended path and the
direction the vehicle is actually traveling. StabiliTrak
®
selectively applies braking pressure at any one of
the vehicle’s brakes to help steer the vehicle in the
direction which you are steering.
When the system activates, a STABILITY SYS ACTIVE
message will be displayed on the Driver Information
Center. SeeDIC Warnings and Messages on page 3-79.
You may also hear a noise or feel vibration in the
brake pedal. This is normal. Continue to steer the
vehicle in the direction you want it to go.
If there is a problem detected with StabiliTrak
®,a
SERVICE STABILITY SYS message will be displayed
on the Driver Information Center. SeeDIC Warnings
and Messages on page 3-79. When this message
is displayed, the system is not operational. Driving
should be adjusted accordingly.
4-11

Once you are moving on the freeway, make certain
you allow a reasonable following distance.
Expect to move slightly slower at night.
When you want to leave the freeway, move to the
proper lane well in advance. If you miss your exit,
do not, under any circumstances, stop and back up.
Drive on to the next exit.
The exit ramp can be curved, sometimes quite sharply.
The exit speed is usually posted. Reduce your speed
according to your speedometer, not to your sense
of motion. After driving for any distance at higher
speeds, you may tend to think you are going slower
than you actually are.
Before Leaving on a Long Trip
Make sure you are ready. Try to be well rested. If you
must start when you are not fresh — such as after
a day’s work — do not plan to make too many miles
that rst part of the journey. Wear comfortable clothing
and shoes you can easily drive in.Is your vehicle ready for a long trip? If you keep it
serviced and maintained, it is ready to go. If it needs
service, have it done before starting out. Of course, you
will nd experienced and able service experts in GM
dealerships all across North America. They will be ready
and willing to help if you need it.
Here are some things you can check before a trip:
Windshield Washer Fluid:Is the reservoir full?
Are all windows clean inside and outside?
Wiper Blades:Are they in good shape?
Fuel, Engine Oil, Other Fluids:Have you checked
all levels?
Lamps:Are they all working? Are the lenses clean?
Tires:They are vitally important to a safe,
trouble-free trip. Is the tread good enough for
long-distance driving? Are the tires all inated to
the recommended pressure?
Weather Forecasts:What is the weather outlook
along your route? Should you delay your trip a
short time to avoid a major storm system?
Maps:Do you have up-to-date maps?
4-24

Highway Hypnosis
Is there actually such a condition as highway hypnosis?
Or is it just plain falling asleep at the wheel? Call it
highway hypnosis, lack of awareness, or whatever.
There is something about an easy stretch of road with
the same scenery, along with the hum of the tires on the
road, the drone of the engine, and the rush of the
wind against the vehicle that can make you sleepy. Do
not let it happen to you! If it does, your vehicle can
leave the road in less than a second, and you could
crash and be injured.
What can you do about highway hypnosis? First, be
aware that it can happen.
Then here are some tips:
Make sure your vehicle is well ventilated, with a
comfortably cool interior.
Keep your eyes moving. Scan the road ahead and
to the sides. Check your rearview mirrors and your
instruments frequently.
If you get sleepy, pull off the road into a rest,
service, or parking area and take a nap, get some
exercise, or both. For safety, treat drowsiness
on the highway as an emergency.
Hill and Mountain Roads
Driving on steep hills or mountains is different from
driving in at or rolling terrain.
4-25

If you put things inside your vehicle, like suitcases,
tools, packages, or anything else, they will go as fast as
the vehicle goes. If you have to stop or turn quickly,
or if there is a crash, they will keep going.
{CAUTION:
Things you put inside your vehicle can strike
and injure people in a sudden stop or turn, or
in a crash.
Put things in the trunk of your vehicle. In a
trunk, put them as far forward as you can.
Try to spread the weight evenly.
Never stack heavier things, like suitcases,
inside the vehicle so that some of them
are above the tops of the seats.
Do not leave an unsecured child restraint
in your vehicle.
When you carry something inside the
vehicle, secure it whenever you can.
Automatic Level Control
This feature keeps the rear of your vehicle level as
the load changes. It is automatic, you do not need to
adjust anything.
Towing
Towing Your Vehicle
Consult your dealer or a professional towing service if
you need to have your disabled vehicle towed. See
Roadside Service on page 7-5.
If you want to tow your vehicle behind another vehicle
for recreational purposes (such as behind a motorhome),
see Recreational Vehicle Towing following.
4-37

When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
start your engine
shift into a gear, and
release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store
the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you are
pulling a trailer. See the Maintenance Schedule for
more on this. Things that are especially important in
trailer operation are automatic transmission uid (do not
overll), engine oil, drive belt, cooling system and
brake system. Each of these is covered in this manual,
and the Index will help you nd them quickly. If you
are trailering, it is a good idea to review this information
before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Engine Cooling When Trailer Towing
Your cooling system may temporarily overheat during
severe operating conditions. SeeEngine Overheating on
page 5-30.
4-46

Service............................................................5-3
Accessories and Modications..........................5-3
California Proposition 65 Warning.....................5-3
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside of
Your Vehicle..............................................5-5
Fuel................................................................5-5
Gasoline Octane............................................5-5
Gasoline Specications....................................5-6
California Fuel...............................................5-6
Additives.......................................................5-6
Fuels in Foreign Countries...............................5-7
Filling the Tank..............................................5-8
Filling a Portable Fuel Container.....................5-10
Checking Things Under the Hood....................5-10
Hood Release..............................................5-11
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-18
Engine Oil Life System..................................5-22
Engine Air Cleaner/Filter................................5-24
Automatic Transmission Fluid.........................5-26
Engine Coolant.............................................5-26
Coolant Surge Tank Pressure Cap..................5-30
Engine Overheating.......................................5-30
Overheated Engine Protection
Operating Mode........................................5-31Cooling System............................................5-32
Power Steering Fluid.....................................5-39
Windshield Washer Fluid................................5-40
Brakes........................................................5-41
Battery........................................................5-44
Jump Starting...............................................5-45
All-Wheel Drive..............................................5-50
Rear Axle.......................................................5-51
Front Axle......................................................5-52
Bulb Replacement..........................................5-53
High Intensity Discharge (HID) Lighting............5-53
Halogen Bulbs..............................................5-53
Back-Up Lamps............................................5-54
Replacement Bulbs.......................................5-54
Windshield Replacement.................................5-55
Windshield Wiper Blade Replacement..............5-55
Tires..............................................................5-56
Tire Sidewall Labeling...................................5-58
Tire Terminology and Denitions.....................5-60
Run-Flat Tires (STS-V)..................................5-63
Ination - Tire Pressure.................................5-64
Tire Pressure Monitor System.........................5-66
Tire Inspection and Rotation...........................5-70
When It Is Time for New Tires.......................5-71
Section 5 Service and Appearance Care
5-1

Buying New Tires.........................................5-72
Different Size Tires and Wheels......................5-74
Uniform Tire Quality Grading..........................5-75
Wheel Alignment and Tire Balance..................5-76
Wheel Replacement......................................5-76
Tire Chains..................................................5-78
Lifting Your Vehicle (STS-V )..........................5-79
If a Tire Goes Flat........................................5-81
Changing a Flat Tire (STS Only).....................5-83
Removing the Spare Tire and Tools
(STS Only)...............................................5-85
Removing the Flat Tire and Installing
the Spare Tire (STS Only)..........................5-86
Storing a Flat or Spare Tire and Tools
(STS Only)...............................................5-92
Compact Spare Tire (STS Only).....................5-94
Appearance Care............................................5-94
Cleaning the Inside of Your Vehicle.................5-94
Fabric/Carpet...............................................5-96
Leather.......................................................5-96
Instrument Panel, Vinyl, and Other
Plastic Surfaces........................................5-97
Wood Panels...............................................5-97
Speaker Covers............................................5-97
Care of Safety Belts......................................5-97Weatherstrips...............................................5-97
Washing Your Vehicle...................................5-98
Cleaning Exterior Lamps/Lenses.....................5-98
Finish Care..................................................5-98
Windshield and Wiper Blades.........................5-99
Aluminum or Chrome-Plated Wheels................5-99
Tires.........................................................5-100
Sheet Metal Damage...................................5-100
Finish Damage...........................................5-101
Underbody Maintenance...............................5-101
Chemical Paint Spotting...............................5-101
Vehicle Care/Appearance Materials................5-102
Vehicle Identication.....................................5-103
Vehicle Identication Number (VIN)................5-103
Service Parts Identication Label...................5-103
Electrical System..........................................5-104
Add-On Electrical Equipment.........................5-104
Headlamp Wiring........................................5-104
Windshield Wiper Fuses...............................5-104
Power Windows and Other Power Options......5-105
Fuses and Circuit Breakers..........................5-105
Underhood Fuse Block................................5-106
Rear Underseat Fuse Block..........................5-110
Capacities and Specications........................5-116
Section 5 Service and Appearance Care
5-2

Service
Your dealer knows your vehicle best and wants you
to be happy with it. We hope you will go to your dealer
for all your service needs. You will get genuine GM
parts and GM-trained and supported service people.
We hope you will want to keep your GM vehicle all GM.
Genuine GM parts have one of these marks:
Accessories and Modications
When you add non-GM accessories to your vehicle
they can affect your vehicle’s performance and safety,
including such things as, airbags, braking, stability,
ride and handling, emissions systems, aerodynamics,
durability, and electronic systems like anti-lock brakes,
traction control and stability control. Some of these
accessories may even cause malfunction or damage
not covered by warranty.
GM Accessories are designed to complement and
function with other systems on your vehicle. Your
GM dealer can accessorize your vehicle using genuine
GM Accessories. When you go to your GM dealer and
ask for GM Accessories, you will know that GM-trained
and supported service technicians will perform the work
using genuine GM Accessories.
California Proposition 65 Warning
Most motor vehicles, including this one, contain
and/or emit chemicals known to the State of California
to cause cancer and birth defects or other reproductive
harm. Engine exhaust, many parts and systems
(including some inside the vehicle), many uids, and
some component wear by-products contain and/or emit
these chemicals.
5-3

Doing Your Own Service Work
{CAUTION:
You can be injured and your vehicle could be
damaged if you try to do service work on a
vehicle without knowing enough about it.
Be sure you have sufficient knowledge,
experience, the proper replacement parts,
and tools before you attempt any vehicle
maintenance task.
Be sure to use the proper nuts, bolts,
and other fasteners. English and metric
fasteners can be easily confused. If you
use the wrong fasteners, parts can later
break or fall off. You could be hurt.If you want to do some of your own service work, you will
want to use the proper service manual. It tells you much
more about how to service your vehicle than this manual
can. To order the proper service manual, seeService
Publications Ordering Information on page 7-14.
Your vehicle has an airbag system. Before attempting
to do your own service work, seeServicing Your
Airbag-Equipped Vehicle on page 1-63.
You should keep a record with all parts receipts and
list the mileage and the date of any service work you
perform. SeeMaintenance Record on page 6-16.
5-4

Adding Equipment to the
Outside of Your Vehicle
Things you might add to the outside of your vehicle can
affect the airow around it. This may cause wind noise
and affect windshield washer performance. Check with
your dealer before adding equipment to the outside of
your vehicle.
Fuel
The 8th digit of your vehicle identication number (VIN)
shows the code letter or number that identies your
engine. You will nd the VIN at the top left of the
instrument panel. SeeVehicle Identication Number
(VIN) on page 5-103.
Gasoline Octane
If your vehicle has the 3.6L V6 engine (VIN Code 7), use
regular unleaded gasoline with a posted octane rating of
87 or higher. For best performance or trailer towing, you
may choose to use middle grade 89 octane unleaded
gasoline. If the octane rating is less than 87, you may
notice an audible knocking noise when you drive,
commonly referred to as spark knock. If this occurs, use a
gasoline rated at 87 octane or higher as soon as possible.
If you are using gasoline rated at 87 octane or higher and
you hear heavy knocking, your engine needs service.
If your vehicle has the 4.6L V8 engine (VIN Code A), use
premium unleaded gasoline with a posted octane rating
of 91 or higher. You may also use regular unleaded
gasoline rated at 87 octane or higher, but your vehicle’s
acceleration may be slightly reduced, and you may notice
a slight audible knocking noise, commonly referred to as
spark knock. If the octane is less than 87, you may notice
a heavy knocking noise when you drive. If this occurs,
use a gasoline rated at 87 octane or higher as soon as
possible. Otherwise, you might damage your engine. If
you are using gasoline rated at 87 octane or higher and
you hear heavy knocking, your engine needs service.
5-5