
Black plate (44,1)Cadillac STS Owner Manual - 2011
The display can be changed from English to metric
units through the Driver Information Center (DIC). See
DIC Operation and Displays on page 4‑70.
Manual Operation
O(Driver's Temperature Control): Press to turn the
entire climate control system on or off. Turn the knob to
increase or decrease the temperature inside the
vehicle.
O (Passenger's Temperature Control): Press to turn
the passenger climate control system on. Turn the knob
to increase or decrease the temperature for the front
passenger only. The passenger side power button does
not turn off the climate control system. The system is
set to the same setting as the driver.
y A z (Fan Control): Press to increase or decrease
the fan speed. This cancels automatic operation and
lets the amount of airflow be adjusted manually. Press
AUTO to return to automatic operation.
If the airflow seems low when the fan speed is at the
highest setting, the passenger compartment air filter
may need to be replaced. For more information, see
Passenger Compartment Air Filter
on page 4‑50and
Scheduled Maintenance on page 7‑3. yN
z(Air Delivery Mode): Press to change the
direction of the airflow in the vehicle. This cancels
automatic operation and lets the air delivery mode be
adjusted manually. Press AUTO to return to automatic
operation.
The outboard air outlets always receive airflow
regardless of the mode selected. See Outlet Adjustment
on page 4‑48to change this airflow from the outboard
outlets.
To change the current mode, select one of the following:
Y (Vent): Air is directed to the instrument panel outlets.
\ (Bi-Level): Air is divided between the instrument
panel outlets and the floor outlets. In automatic
operation, cooler air is directed to the upper outlets
and warmer air to the floor outlets.
[ (Floor): Air is directed to the floor outlets, with some
air directed to the windshield and side windows.
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Black plate (50,1)Cadillac STS Owner Manual - 2011
Passenger Compartment Air Filter
Your vehicle may be equipped with a passenger
compartment air filter. There are two types of filters
available. There is a standard dust filter that traps small
particles including pollen. There is, also, a dust/odor
filter available that traps dust and pollen and uses a
charcoal element to help reduce many offensive odors
from entering your vehicle. The filter will need to be
changed periodically. For information on when to
change the passenger compartment air filter, see
Scheduled Maintenance on page 7‑3.
Notice:Driving without a passenger compartment
air filter in place can cause water and small
particles, like paper and leaves, to be pulled into
your climate control system which may cause
damage to it. Make sure you always replace the old
filter with a new one.
The access panel for the passenger compartment air
filter is located under the hood near the windshield,
on the passenger side of the vehicle. See Engine
Compartment Overview
on page 6‑13for more
information on location. See Doing Your Own Service
Work
on page 6‑5for information on doing your own
service work.
To access the passenger compartment air filter:
1. Pull back the rubber hood seal from the edge of the leaf screen vent cover.
2. Remove the three fasteners that hold the filter cover in place and slide the cover off.
3. To access the filter, remove the water deflector by lifting the outboard edge of the deflector to release
the retention tab.
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Black plate (63,1)Cadillac STS Owner Manual - 2011
This light should come on
when the ignition is on,
but the engine is not
running, as a check to
show it is working. If it
does not, have the vehicle
serviced by your dealer.
If the check engine light comes on and stays on, while
the engine is running, this indicates that there is an
OBD II problem and service is required.
Malfunctions often are indicated by the system before
any problem is apparent. Being aware of the light can
prevent more serious damage to the vehicle. This
system assists the service technician in correctly
diagnosing any malfunction.
Notice: If the vehicle is continually driven with this
light on, after a while, the emission controls might
not work as well, the vehicle fuel economy might
not be as good, and the engine might not run as
smoothly. This could lead to costly repairs that
might not be covered by the vehicle warranty. Notice:
Modifications made to the engine,
transmission, exhaust, intake, or fuel system of the
vehicle or the replacement of the original tires with
other than those of the same Tire Performance
Criteria (TPC) can affect the vehicle's emission
controls and can cause this light to come on.
Modifications to these systems could lead to costly
repairs not covered by the vehicle warranty. This
could also result in a failure to pass a required
Emission Inspection/Maintenance test. See
Accessories and Modifications on page 6‑4.
This light comes on during a malfunction in one of
two ways:
Light Flashing: A misfire condition has been detected.
A misfire increases vehicle emissions and could
damage the emission control system on the vehicle.
Diagnosis and service might be required.
To prevent more serious damage to the vehicle:
.Reduce vehicle speed.
.Avoid hard accelerations.
.Avoid steep uphill grades.
.If towing a trailer, reduce the amount of cargo
being hauled as soon as it is possible.
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Black plate (65,1)Cadillac STS Owner Manual - 2011
Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments may have
programs to inspect the on-vehicle emission control
equipment For the inspection, the emission system test
equipment is connected to the vehicle’s Data Link
Connector (DLC).
The DLC is under the instrument panel to the left of the
steering wheel. See your dealer if assistance is needed.The vehicle may not pass inspection if:
.the Malfunction Indicator Lamp is on with the
engine running, or if the light does not come on
when the ignition is turned to ON/RUN while the
engine is off.
.the critical emission control systems have not been
completely diagnosed by the system. This can
happen if the battery has recently been replaced or
if the battery has run down. The diagnostic system
evaluates critical emission control systems during
normal driving. This can take several days of
routine driving. If this has been done and the
vehicle still does not pass the inspection, your
dealer can prepare the vehicle for inspection.
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Black plate (66,1)Cadillac STS Owner Manual - 2011
Oil Pressure Light
For vehicles with an oil
pressure light, if there is a
problem with the oil, the
light may stay on after
the engine is started,
or comes on while driving.
This light indicates that oil is not going through the
engine quickly enough to keep it lubricated. The engine
could be low on oil or could have some other oil
problem. Have the vehicle serviced by your dealer.
The oil light could also come on in the following
situations:
.The light comes on briefly when the ignition is
turned on to show that it is working properly. If it
does not come on with the ignition on, there may
be a problem with the fuse or bulb. Have the
vehicle serviced by your dealer.
.Sometimes when the engine is idling at a stop, a
chime sounds and the light may blink on and off.
This is normal.
{WARNING:
Do not keep driving if the oil pressure is low. The
engine can become so hot that it catches fire.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.
Notice: Lack of proper engine oil maintenance can
damage the engine. The repairs would not be
covered by the vehicle warranty. Always follow the
maintenance schedule for changing engine oil.
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Black plate (74,1)Cadillac STS Owner Manual - 2011
BATTERY VOLTS
This display shows the current battery voltage. If the
voltage is in the normal range, the value will display.
For example, the display may read 13.2 BATTERY
VOLTS. If the voltage is low, the display will have
LOW after it. If the voltage is high, the display will have
HIGH after it. Your vehicle's charging system regulates
voltage based on the state of the battery. The battery
voltage may fluctuate when viewing this information
on the DIC. This is normal. SeeCharging System Light
on page 4‑57for more information.
If there is a problem with the battery charging system,
the DIC may display a message. See DIC Warnings
and Messages
on page 4‑76and Electric Power
Managementon page 4‑37for more information.
Tire Pressure
This display shows the pressure for each tire in either
pounds per square inch (psi) or kilopascals (kPa). If the
tire pressure is normal, the value will display. If the tire
pressure is low, LOW will appear on the display with the
value. See Inflation - Tire Pressure
on page 6‑58and
DIC Warnings and Messageson page 4‑76for more
information. Press the information button to scroll
through the following displays:
LF TIRE: This display shows the pressure in the driver
side front tire. RF TIRE:
This display shows the pressure in the
passenger side front tire.
LR TIRE: This display shows the pressure in the driver
side rear tire.
RR TIRE: This display shows the pressure in the
passenger side rear tire.
If the tire pressure display shows dashes instead of a
value, there may be a problem with your vehicle. If this
consistently occurs, see your dealer for service.
ENGINE OIL LIFE
If your vehicle has this display, it shows the estimated
oil life remaining. If you see 99% ENGINE OIL LIFE on
the display, that means that 99% of the current oil life
remains.
When the oil life is depleted, the CHANGE ENGINE OIL
SOON message will appear on the display. Change the
oil as soon as possible. In addition to the engine oil life
system monitoring the oil life, additional maintenance is
recommended in the Maintenance Schedule in this
manual. See Scheduled Maintenance
on page 7‑3andEngine Oil on page 6‑16.
After an oil change, reset the ENGINE OIL LIFE display.
To reset, see Engine Oil Life System
on page 6‑20.
The display will show 100% ENGINE OIL LIFE after it
has been reset. Also clear the CHANGE ENGINE OIL
SOON message from the display.
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Black plate (78,1)Cadillac STS Owner Manual - 2011
BATTERY VOLTAGE LOW
This symbol appears
with this message.
This message displays when the electrical system is
charging less than 10 volts or the battery has been
drained.
If this message appears immediately after starting
the engine, it is possible that the generator can still
recharge the battery. The battery should recharge while
driving, but may take a few hours to do so. Consider
using an auxiliary charger to boost the battery after
returning home or to a final destination. Follow the
manufacturer's instructions.
If this message appears while driving or after starting
your vehicle and stays on, have it checked immediately
to determine the cause of this problem.
To help the generator recharge the battery quickly,
reduce the load on the electrical system by turning
off the accessories. The normal battery voltage range is 11.5 to 15.5 volts.
To monitor battery voltage on the DIC, press the
information button until BATTERY VOLTS displays.
CHANGE ENGINE OIL SOON
This message displays when the engine oil needs
to be changed. See your dealer. See
Engine Oilon
page 6‑16and Scheduled Maintenanceon page 7‑3for more information.
After resetting the CHANGE ENGINE OIL SOON
message by clearing it from the display, reset the
engine oil life system separately. For more information
on resetting the engine oil life system, see Engine Oil
Life System on page 6‑20.
CHECK BRAKE FLUID
This message displays if the ignition is on to inform the
driver that the brake fluid level is low. Have the brake
system serviced by your dealer as soon as possible.
See Brake System Warning Light
on page 4‑58for
more information.
CHECK GAS CAP
This message displays when the fuel cap has not been
fully tightened. Recheck the fuel cap to ensure that it is
on and tightened properly.
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Black plate (38,1)Cadillac STS Owner Manual - 2011
Leaving After Parking on a Hill
1. Apply and hold the brake pedal while you:
.Start the engine
.Shift into a gear
.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
The vehicle needs service more often when pulling a
trailer. See this manual's Maintenance Schedule or
Index for more information. Things that are especially
important in trailer operation are automatic transmission
fluid, engine oil, axle lubricant, belts, cooling system
and brake system. It is a good idea to inspect these
before and during the trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Engine Cooling When Trailer Towing
The cooling system may temporarily overheat during
severe operating conditions. See Engine Overheating
on page 6‑30.
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