
Black plate (26,1)Cadillac STS Owner Manual - 2011
What to Use
{WARNING:
Adding only plain water or some other liquid to the
cooling system can be dangerous. Plain water
and other liquids, can boil before the proper
coolant mixture will. The vehicle's coolant warning
system is set for the proper coolant mixture. With
plain water or the wrong mixture, the engine could
get too hot but you would not get the overheat
warning. The engine could catch fire and you or
others could be burned. Use a 50/50 mixture of
clean, drinkable water and DEX-COOL coolant.
Use a 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant. If using this mixture, nothing else
needs to be added. This mixture:
.Gives freezing protection down to −34°F (−37°C),
outside temperature.
.Gives boiling protection up to 265°F (129°C),
engine temperature.
.Protects against rust and corrosion.
.Will not damage aluminum parts.
.Helps keep the proper engine temperature.
Notice: If an improper coolant mixture is used, the
engine could overheat and be badly damaged. The
repair cost would not be covered by the vehicle
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core, and
other parts.
Notice: If extra inhibitors and/or additives are used
in the vehicle's cooling system, the vehicle could be
damaged. Use only the proper mixture of the engine
coolant listed in this manual for the cooling system.
See Recommended Fluids and Lubricants
on
page 7‑9for more information.
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Black plate (30,1)Cadillac STS Owner Manual - 2011
4. With the coolant surge tank pressure cap off, startthe engine and let it run until you can feel the
upper radiator hose getting hot. The upper radiator
hose is the largest of the hoses which comes out
of the radiator, on the passenger side of the
vehicle. Watch out for the engine cooling fans.
By this time, the coolant level inside the coolant
surge tank may be lower. If the level is lower, add
more of the proper mixture to the coolant surge
tank until the level reaches the FULL COLD/FROID
line on the side of the coolant surge tank.
5. Then replace the pressure cap. Be sure the pressure cap is hand-tight and fully seated.
Start the engine and allow it to warm up.
Engine Overheating
The vehicle has several indicators to warn of engine
overheating.
There are two engine hot messages that could be
displayed in the Driver Information Center (DIC). See
DIC Warnings and Messages
on page 4‑76DIC
Warnings and Messages for more information. If the engine is overheating, then you will find a coolant
temperature gauge and a coolant warning light on the
instrument panel. See
Engine Coolant Temperature
Gauge
on page 4‑61and Engine Coolant Temperature
Warning Lighton page 4‑61for more information.
You may decide not to lift the hood when this warning
appears, but instead get service help right away. See
Roadside Service on page 8‑8.
If you do decide to lift the hood , make sure the vehicle
is parked on a level surface.
Then check to see if the engine cooling fans are
running. If the engine is overheating, both fans should
be running. If they are not, do not continue to run the
engine and have the vehicle serviced.
Notice: Engine damage from running your engine
without coolant is not covered by the vehicle
warranty. See Overheated Engine Protection
Operating Mode for information on driving to a safe
place in an emergency.
Notice: If the engine catches fire while driving with
no coolant, the vehicle can be badly damaged. The
costly repairs would not be covered by the vehicle
warranty. See Overheated Engine Protection
Operating Mode
on page 6‑32for information on
driving to a safe place in an emergency.
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Black plate (31,1)Cadillac STS Owner Manual - 2011
If Steam Is Coming From The Engine
Compartment
{WARNING:
Steam from an overheated engine can burn you
badly, even if you just open the hood. Stay away
from the engine if you see or hear steam coming
from it. Turn it off and get everyone away from the
vehicle until it cools down. Wait until there is no
sign of steam or coolant before you open
the hood.
If you keep driving when the vehicles engine is
overheated, the liquids in it can catch fire. You or
others could be badly burned. Stop the engine if it
overheats, and get out of the vehicle until the
engine is cool.
SeeOverheated Engine Protection Operating
Mode
on page 6‑32for information on driving to
a safe place in an emergency.
If No Steam Is Coming From The
Engine Compartment
An overheat warning, can indicate a serious problem.
If an engine overheat warning is displayed but no steam
can be seen or heard, the problem may not be too
serious. Sometimes the engine can get a little too hot
when the vehicle:
.Climbs a long hill on a hot day.
.Stops after high-speed driving.
.Idles for long periods in traffic.
.Tows a trailer.
If the overheat warning is displayed with no sign of
steam: 1. Turn the air off.
2. Turn the heater on to the highest temperature and to the highest fan speed. Open the windows as
necessary.
3. In heavy traffic, let the engine idle in N (Neutral) while stopped. If it is safe to do so, pull off the
road, shift to P (Park) or N (Neutral) and let the
engine idle.
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Black plate (32,1)Cadillac STS Owner Manual - 2011
If the engine coolant temperature gauge is no longer in
the overheat zone or an overheat warning no longer
displays, the vehicle can be driven. Continue to drive
the vehicle slow for about 10 minutes. Keep a safe
vehicle distance from the car in front of you. If the
warning does not come back on, continue to drive
normally.
If the warning continues, pull over, stop, and park the
vehicle right away.
If there is no sign of steam, idle the engine for
three minutes while parked. If the warning is still
displayed, turn off the engine until it cools down. Also,
see "Overheated Engine Protection Operating Mode"
later in this section.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 firing groups of cylinders helps prevent
engine damage. In this mode, you will notice a loss in
power and engine performance. An 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.
See Engine Oil on page 6‑16.
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Black plate (34,1)Cadillac STS Owner Manual - 2011
Windshield Washer Fluid
What to Use
When you need windshield washer fluid, be sure to
read the manufacturer's instructions before use. If you
will be operating your vehicle in an area where the
temperature may fall below freezing, use a fluid that has
sufficient protection against freezing.
Adding Washer Fluid
The CHECK WASHER FLUID message will appear on
the Driver Information Center (DIC) when the fluid level
is low. SeeDIC Warnings and Messages
on page 4‑76for more information.
Open the cap with the
washer symbol on it.
Add washer fluid until the
tank is full. See Engine
Compartment Overview
on page 6‑13for
reservoir location.
Notice:
.When using concentrated washer fluid,
follow the manufacturer's instructions for
adding water.
.Do not mix water with ready-to-use washer
fluid. Water can cause the solution to freeze
and damage the washer fluid tank and other
parts of the washer system. Also, water does
not clean as well as washer fluid.
.Fill the washer fluid tank only three-quarters
full when it is very cold. This allows for fluid
expansion if freezing occurs, which could
damage the tank if it is completely full.
.Do not use engine coolant (antifreeze) in
the windshield washer. It can damage the
windshield washer system and paint.
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Black plate (4,1)Cadillac STS Owner Manual - 2011
Convenience Net . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-57
CoolantEngine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-25
Engine Temperature Gauge . . . . . . . . . . . . . . . . . . . . . . 4-61
Engine Temperature Warning Light . . . . . . . . . . . . . . . 4-61
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-24
Courtesy Transportation Program . . . . . . . . . . . . . . . . . . 8-12
Cruise Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-12 Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-67
Cruise Control, Active . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-15
Cruise Control, Forward Collision Alert (FCA) System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-6
Cupholders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-56
Customer Assistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-6 Text Telephone (TTY) Users . . . . . . . . . . . . . . . . . . . . . . . 8-6
Customer Assistance Offices . . . . . . . . . . . . . . . . . . . . . . . .8-6
Customer Information
Service Publications Ordering Information . . . . . . . . 8-17
Customer Satisfaction Procedure . . . . . . . . . . . . . . . . . . . .8-2
D
Damage Repair, Collision . . . . . . . . . . . . . . . . . . . . . . . . . . 8-13
Data Recorders, Event . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-19
Daytime Running Lamps (DRL) . . . . . . . . . . . . . . . . . . . . 4-32
Defensive Driving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-2
Disc, MP3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-108 Displays
Head-Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-38
Doing Your Own Service Work . . . . . . . . . . . . . . . . . . . . . . .6-5
Door Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-12
Power Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13
Programmable Automatic Door Locks . . . . . . . . . . . . 3-14
Rear Door Security Locks . . . . . . . . . . . . . . . . . . . . . . . . 3-14
Drive Systems All-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-43
Driver Information Center (DIC) . . . . . . . . . . . . . . . . . . . . 4-69
DIC Operation and Displays . . . . . . . . . . . . . . . . . . . . . . 4-70
DIC Warnings and Messages . . . . . . . . . . . . . . . . . . . . . 4-76
Other Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-93
Driving At Night . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-16
Before a Long Trip . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-18
Defensive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2
Drunk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2
Highway Hypnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-18
Hill and Mountain Roads . . . . . . . . . . . . . . . . . . . . . . . . . . 5-19
In Rain and on Wet Roads . . . . . . . . . . . . . . . . . . . . . . . . 5-16
Loss of Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-14
Off-Road Recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-14
Rocking Your Vehicle to Get it Out . . . . . . . . . . . . . . . . 5-23
Winter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-20
Driving for Better Fuel Economy . . . . . . . . . . . . . . . . . . . 1-23
Dual Climate Control System . . . . . . . . . . . . . . . . . . . . . . 4-43
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Black plate (5,1)Cadillac STS Owner Manual - 2011
E
EDR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-19
Electrical Equipment, Add-On . . . . . . . . . . . . . . . . . . . . 6-114
Electrical SystemFuses and Circuit Breakers . . . . . . . . . . . . . . . . . . . . . . 6-115
Headlamp Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-115
Power Windows and Other Power Options . . . . . . 6-115
Rear Underseat Fuse Block . . . . . . . . . . . . . . . . . . . . .6-120
Underhood Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . 6-116
Windshield Wiper Fuses . . . . . . . . . . . . . . . . . . . . . . . . . 6-115
Engine
Air Cleaner/Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-21
Check and Service Engine Soon Light . . . . . . . . . . . . 4-62
Compartment Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-13
Coolant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-25
Coolant Heater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-29
Coolant Temperature Gauge . . . . . . . . . . . . . . . . . . . . . . 4-61
Coolant Temperature Warning Light . . . . . . . . . . . . . . 4-61
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-24
Drive Belt Routing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-12
Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-36
Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-16
Overheated Protection Operating Mode . . . . . . . . . . 6-32
Overheating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-30
Starting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-27
Engine Oil Life System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-20 Enhanced StabiliTrak
®. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-7
Entry Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-36
Event Data Recorders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-19
Extender, Safety Belt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-34
Exterior Lighting Battery Saver . . . . . . . . . . . . . . . . . . . . 4-35
F
Filter Engine Air Cleaner . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-21
Finish Damage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-113
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-9
Flashers, Hazard Warning . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3
Flat Tire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-74
Flat Tire, Changing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-94
Flat Tire, Storing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-103
Floor Mats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-56
Fluid Automatic Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . 6-23
Power Steering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-33
Windshield Washer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-34
Fog Lamps Bulb Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-33
Forward Collision Alert (FCA) System . . . . . . . . . . . . . . .4-6
Front Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-45
Front Fog Lamps
Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-67
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Black plate (6,1)Cadillac STS Owner Manual - 2011
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-6Additives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
California Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
Filling a Portable Fuel Container . . . . . . . . . . . . . . . . . . 6-11
Filling the Tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-9
Fuels in Foreign Countries . . . . . . . . . . . . . . . . . . . . . . . . . 6-8
Gasoline Octane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Gasoline Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
Gauge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-68
Fuel Economy Driving for Better . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-23
Fuses Fuses and Circuit Breakers . . . . . . . . . . . . . . . . . . . . . . 6-115
Rear Underseat Fuse Block . . . . . . . . . . . . . . . . . . . . .6-120
Underhood Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . 6-116
Windshield Wiper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-115
G
Garage Door Opener . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-49
GasolineOctane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7 Gauges
Engine Coolant Temperature . . . . . . . . . . . . . . . . . . . . . 4-61
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-68
Speedometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-53
Tachometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-53
Glove Box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-56
GM Mobility Reimbursement Program . . . . . . . . . . . . . . .8-7
H
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-47
Hazard Warning Flashers . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3
Head Restraints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12
Head-Up Display (HUD) . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-38
Headlamp Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-115
Headlamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-27 Aiming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-46
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-47
Daytime Running Lamps (DRL) . . . . . . . . . . . . . . . . . . . 4-32
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-9
High Intensity Discharge (HID) Lighting . . . . . . . . . . . 6-47
High/Low Beam Changer . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5
On Reminder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-31
Range Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12
Washer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-11
Wiper Activated . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-31
Heated Steering Wheel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
i - 6