
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 (7,1)Cadillac STS Owner Manual - 2011
Gasoline Specifications
At a minimum, gasoline should meet ASTM
specification D 4814 in the United States or
CAN/CGSB‐3.5 or 3.511 in Canada. Some gasolines
contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl (MMT).
We recommend against the use of gasolines containing
MMT. SeeAdditives
on page 6‑7for additional
information.
California Fuel
If the vehicle is certified to meet California Emissions
Standards, it is designed to operate on fuels that meet
California specifications. See the underhood emission
control label. If this fuel is not available in states
adopting California emissions standards, the vehicle
will operate satisfactorily on fuels meeting federal
specifications, but emission control system performance
might be affected. The malfunction indicator lamp could
turn on and the vehicle might fail a smog‐check test.
See Malfunction Indicator Lamp
on page 4‑62. If this
occurs, return to your authorized dealer for diagnosis.
If it is determined that the condition is caused by the
type of fuel used, repairs might not be covered by the
vehicle warranty.
Additives
To provide cleaner air, all gasolines in the United States
are now required to contain additives that help prevent
engine and fuel system deposits from forming, allowing
the emission control system to work properly. In most
cases, nothing should have to be added to the fuel.
However, some gasolines contain only the minimum
amount of additive required to meet U.S. Environmental
Protection Agency regulations. To help keep fuel
injectors and intake valves clean, or if the vehicle
experiences problems due to dirty injectors or valves,
look for gasoline that is advertised as TOP TIER
Detergent Gasoline.
For customers who do not use TOP TIER Detergent
Gasoline regularly, one bottle of GM Fuel System
Treatment PLUS, added to the fuel tank at every engine
oil change, can help clean deposits from fuel injectors
and intake valves. GM Fuel System Treatment PLUS is
the only gasoline additive recommended by General
Motors. It is available at your dealer.
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Black plate (16,1)Cadillac STS Owner Manual - 2011
Engine Oil
To ensure proper engine performance and long life,
careful attention must be paid to engine oil. Following
these simple, but important steps will help protect your
investment:
.Always use engine oil approved to the proper
specification and of the proper viscosity grade. See
“Selecting the Right Engine Oil.”
.Check the engine oil level regularly and maintain
the proper oil level. See“Checking Engine Oil”and
“When to Add Engine Oil.”
.Change the engine oil at the appropriate time. See
Engine Oil Life System on page 6‑20.
.Always dispose of engine oil properly. See “What
to Do With Used Oil.”
Checking Engine Oil
It is a good idea to check the engine oil level at each
fuel fill. In order to get an accurate reading, the vehicle
must be on level ground. The engine oil dipstick handle
is a yellow loop. See Engine Compartment Overview
on
page 6‑13for the location of the engine oil dipstick.
Obtaining an accurate oil level reading is essential: 1. If the engine has been running recently, turn off the engine and allow several minutes for the oil to
drain back into the oil pan. Checking your oil level
too soon after engine shut off will not provide an
accurate oil level reading.
2. Pull out the dipstick and clean it with a paper towel or cloth, then push it back in all the way. Remove it
again, keeping the tip down, and check the level.
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Black plate (18,1)Cadillac STS Owner Manual - 2011
Selecting the Right Engine Oil
Selecting the right engine oil depends on both the
proper oil specification and viscosity grade:
Specification
Use and ask for engine oils with the dexos™
certification mark. Oils meeting the requirements of your
vehicle should have the dexos™certification mark on
the container. This certification mark indicates that the
oil has been approved to the dexos™ specification.
Your vehicle was filled at the factory with dexos™
approved engine oil. Notice:
Use only engine oil that is approved to the
dexos™ specification or an equivalent engine oil
of the appropriate viscosity grade. Engine oils
approved to the dexos™ specification will show the
dexos™ symbol on the container. Failure to use the
recommended engine oil or equivalent can result in
engine damage not covered by the vehicle warranty.
If you are unsure whether your oil is approved to
the dexos™ specification, ask your service provider.
Use of Substitute Engine Oils if dexos™ is unavailable:
In the event that dexos™ approved engine oil is not
available at an oil change or for maintaining proper oil
level, you may use substitute engine oil displaying the
API Starburst symbol and of SAE 5W-30 viscosity
grade. Use of oils that do not meet the dexos™
specification, however, may result in reduced
performance under certain circumstances.
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Black plate (20,1)Cadillac STS Owner Manual - 2011
What to Do with Used Oil
Used engine oil contains certain elements that can be
unhealthy for your skin and could even cause cancer.
Do not let used oil stay on your skin for very long. Clean
your skin and nails with soap and water, or a good hand
cleaner. Wash or properly dispose of clothing or rags
containing used engine oil. See the manufacturer's
warnings about the use and disposal of oil products.
Used oil can be a threat to the environment. If you
change your own oil, be sure to drain all the oil from
the filter before disposal. Never dispose of oil by putting
it in the trash or pouring it on the ground, into sewers,
or into streams or bodies of water. Recycle it by taking it
to a place that collects used oil.
Engine Oil Life System
When to Change Engine Oil
This vehicle has a computer system that indicates when
to change the engine oil and filter. This is based on
engine revolutions and engine temperature, and not on
mileage. Based on driving conditions, the mileage at
which an oil change is indicated can vary considerably.
For the oil life system to work properly, the system must
be reset every time the oil is changed.When the system has calculated that oil life has been
diminished, it indicates that an oil change is necessary.
A CHANGE ENGINE OIL SOON message in the DIC
comes on. See
DIC Warnings and Messages
on
page 4‑76. Change the oil as soon as possible within
the next 600 miles (1 000 km). It is possible that,
if driving under the best conditions, the oil life system
might indicate that an oil change is not necessary for up
to a year. The engine oil and filter must be changed at
least once a year and, at this time, the system must be
reset. Your dealer has trained service people who will
perform this work and reset the system. It is also
important to check the oil regularly over the course of
an oil drain interval and keep it at the proper level.
If the system is ever reset accidentally, the oil must be
changed at 3,000 miles (5 000 km) since the last oil
change. Remember to reset the oil life system
whenever the oil is changed.
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Black plate (21,1)Cadillac STS Owner Manual - 2011
How to Reset the Engine Oil Life
System
Reset the system whenever the engine oil is changed
so that the system can calculate the next engine oil
change. To reset the system:1. Press the up or down arrow to scroll the DIC to show OIL LIFE.
2. Once the XXX% ENGINE OIL LIFE menu item is highlighted, press and hold the RESET button until
the percentage shows 100%.
If the percentage does not return to 100% or if the
CHANGE ENGINE OIL SOON message comes back on
when the vehicle is started, the engine oil life system
has not been reset. Repeat the procedure.
Engine Air Cleaner/Filter
The engine air cleaner/filter is in the engine
compartment on the driver's side of the vehicle, near
the front. See Engine Compartment Overview
on
page 6‑13for more information on locating the air
cleaner/filter.
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Black plate (22,1)Cadillac STS Owner Manual - 2011
When to Inspect the Engine Air
Cleaner/Filter
Inspect the air cleaner/filter at the scheduled
maintenance intervals and replace it at the first oil
change after each 80 000 km (50,000 mile) interval. See
Scheduled Maintenance
on page 7‑3for more
information. If you are driving in dusty/dirty conditions,
inspect the filter at each engine oil change.
How to Inspect the Engine Air
Cleaner/Filter
To inspect the air cleaner/filter remove the filter from the
vehicle and lightly shake the filter to release loose dust
and dirt. If the filter remains caked with dirt, a new filter
is required.
To inspect or replace the filter:
1. Remove the two screws located on the top of the cover.
2. Disconnect the coolant recovery hose so that it is not going across the top of the engine air cleaner/
filter.
3. Loosen the clamp and remove the duct from the passenger's side of the engine air cleaner/filter. 4. The two sides of the airbox are hinged at the
bottom. Open the airbox by pushing the top of the
airbox cover toward the engine.
5. Remove the air filter by lifting it straight up through the opening in the airbox.
6. Inspect or replace the engine air cleaner/filter. See Maintenance Replacement Parts
on page 7‑11for
the correct part number for the filter.
7. Reinstall the cover by reversing Steps 1 through 4.
{WARNING:
Operating the engine with the air cleaner/filter off
can cause you or others to be burned. The air
cleaner not only cleans the air; it helps to stop
flames if the engine backfires. Use caution when
working on the engine and do not drive with the
air cleaner/filter off.
Notice: If the air cleaner/filter is off, dirt can easily
get into the engine, which could damage it. Always
have the air cleaner/filter in place when you are
driving.
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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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