2009 CADILLAC STS engine

Electric Power Management
The vehicle has Electric Power Management (EPM) that
estimates the battery’s temperature and state of charge.
It then adjusts the voltage for best performance and
extended life of the battery.
When the battery’s state of charge is low, the voltage is
raised slightly to quickly bring the charge back up. When
the state of charge is high, the voltage is lowered slightly
to prevent overcharging. If the vehicle has a voltmeter
gage or a voltage display on the Driver Information
Center (DIC), you may see the voltage move up or
down. This is normal. If there is a problem, an alert
will be displayed.
The battery can be discharged at idle if the electrical
loads are very high. This is true for all vehicles. This is
because the generator (alternator) may not be spinning
fast enough at idle to produce all the power that is
needed for very high electrical loads.
A high electrical load occurs when several of the
following are on: headlamps, high beams, fog lamps,
rear window defogger, climate control fan at high speed,
heated seats, engine cooling fans, trailer loads, and
loads plugged into accessory power outlets.EPM works to prevent excessive discharge of the
battery. It does this by balancing the generator’s output
and the vehicle’s electrical needs. It can increase
engine idle speed to generate more power, whenever
needed. It can temporarily reduce the power demands
of some accessories.
Normally, these actions occur in steps or levels, without
being noticeable. In rare cases at the highest levels of
corrective action, this action may be noticeable to the
driver. If so, a Driver Information Center (DIC) message
might be displayed, such as Battery Saver Active or
Service Battery Charging System. If this message is
displayed, it is recommended that the driver reduce the
electrical loads as much as possible. SeeDIC Warnings
and Messages on page 3-79.
Inadvertent Power Battery Saver
This feature is designed to protect the vehicle’s battery
against drainage from the interior lamps, trunk lamp,
glove box lamp, or the garage door opener. When the
ignition is turned off, the power to these features will
automatically turn off after 10 minutes (three minutes
if a new car has 15 miles (24 km) or less). Power will
be restored for an additional 10 minutes if any door
is opened, the trunk is opened or the courtesy lamp
switch is turned on.
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The HUD controls are located to the left of the steering
wheel on the DIC control panel.
Off:Turn the brightness control knob fully
counterclockwise to turn the HUD display off.
~(Head-Up Display):Press to move the HUD
display up or down on the windshield. HUD cannot be
adjusted side-to-side.Brightness Control:Press the knob on the center of
the DIC control panel to extend and then pull the knob
until is completely extended. Turn the knob clockwise or
counterclockwise to increase or decrease the brightness
of the HUD display.
To adjust the HUD so it can be seen properly:
1. Adjust the seat to a comfortable driving position,
before adjusting the HUD position.
2. Start the engine.
3. Adjust the position and brightness of the HUD
display.
The brightness of the HUD display is determined by the
light conditions in the direction the vehicle is facing and
where the HUD has been positioned on the windshield.
If the vehicle is facing a dark object or a heavily shaded
area, the HUD may begin to dim because it anticipates
the vehicle entering a dark area.
When sunlight enters the HUD it can make it difficult
to see the display. The display will return to normal
brightness when the sunlight no longer enters the HUD.
Wearing polarized sunglasses could also make the
HUD display harder to see.
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Rear Window Defogger
The rear window defogger uses a warming grid to
remove fog or frost from the rear window.
The defogger only works when the ignition is on or
during remote start, if programmed. See “Personal
Settings Menu” underVehicle Personalization on
page 2-61for additional information.
=(Rear Window Defogger):Press to turn the rear
window defogger on or off. The rear window defogger
stays on for 10 minutes, before turning off.
If the vehicle’s speed is above 30 mph (48 km/h), the
rear defogger stays on continuously. If turned on again,
the defogger only runs for about ve minutes before
turning off. The defogger can also be turned off by
turning off the engine.The heated outside rearview mirrors also heat to help
clear fog or frost from the surface of the mirror when
the rear window defogger is on. SeeOutside Heated
Mirrors on page 2-41.
Notice:Do not use a razor blade or sharp object to
clear the inside rear window. Do not adhere anything
to the defogger grid lines in the rear glass. These
actions may damage the rear defogger. Repairs
would not be covered by your warranty.
{(Ventilated Seat):If the vehicle has this feature,
press to turn the driver or passenger side ventilated seat
on. SeeHeated and Ventilated Seats on page 1-3.
J(Heated Seat):If the vehicle has this feature, press
to turn the driver or passenger side heated seat and
seatback on. SeeHeated and Ventilated Seats on
page 1-3.
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Passenger Compartment Air Filter
Your vehicle may be equipped with a passenger
compartment air lter. There are two types of lters
available. There is a standard dust lter that traps small
particles including pollen. There is, also, a dust/odor lter
available that traps dust and pollen and uses a charcoal
element to help reduce many offensive odors from
entering your vehicle. The lter will need to be changed
periodically. For information on when to change the
passenger compartment air lter, seeScheduled
Maintenance on page 6-4.
Notice:Driving without a passenger compartment
air lter 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 lter with a new one.The access panel for the passenger compartment air
lter is located under the hood near the windshield, on the
passenger side of the vehicle. SeeEngine Compartment
Overview on page 5-12for more information on location.
SeeDoing Your Own Service Work on page 5-4for
information on doing your own service work.
To access the passenger compartment air lter:
1. Pull back the rubber hood seal from the edge of the
leaf screen vent cover.
2. Remove the three fasteners that hold the lter
cover in place and slide the cover off.
3. To access the lter, remove the water deector by
lifting the outboard edge of the deector to release
the retention tab.
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4. Lift the inboard edge of the deector to release the
retention tab.
5. Lift and slide the water deector toward the inboard
side and remove it.
6. The top edge of the lter should be visible. Reach
in and lift the lter out, pulling upward and toward
the front of the vehicle.
7. Insert the new air lter by sliding it back into place.
Make sure the arrow on the lter is pointing toward
the passenger compartment.
Reverse steps 1 through 3 to reinstall the water
deector, lter cover and the hood seal.Warning Lights, Gages, and
Indicators
Warning lights and gages can signal that something is
wrong before it becomes serious enough to cause an
expensive repair or replacement. Paying attention to
the warning lights and gages could prevent injury.
Warning lights come on when there may be or is a
problem with one of the vehicle’s functions. Some
warning lights come on briey when the engine is
started to indicate they are working.
Gages can indicate when there may be or is a problem
with one of the vehicle’s functions. Often gages and
warning lights work together to indicate a problem with
the vehicle.
When one of the warning lights comes on and stays on
while driving, or when one of the gages shows there may
be a problem, check the section that explains what to do.
Follow this manual’s advice. Waiting to do repairs can be
costly and even dangerous.
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Speedometer and Odometer
The speedometer shows the speed in both miles
per hour (mph) and kilometers per hour (km/h).
See “MPH (km)” underDIC Operation and Displays
on page 3-72for more information.
The odometer mileage can be checked without the
vehicle running. The vehicle’s odometer works together
with the driver information center. The odometer can
be set for a Trip A and a Trip B. See “Trip Information”
underDIC Operation and Displays on page 3-72for
more information.
If the vehicle ever needs a new odometer installed,
the new one will be set to the correct mileage total
of the old odometer.
Tachometer
This gage indicates the engine speed in revolutions
per minute (rpm).
Safety Belt Reminders
Driver Safety Belt Reminder Light
When the engine is started, a chime sounds for
several seconds to remind the driver to fasten the safety
belt, unless the driver’s safety belt is already buckled.
The driver safety belt light
comes on and stays on
for several seconds,
then ashes for
several more.
This chime and light are repeated if the driver remains
unbuckled and the vehicle is in motion. If the driver’s
safety belt is already buckled, neither the chime nor
the light comes on.
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Passenger Safety Belt Reminder Light
Several seconds after the engine is started,
a chime sounds for several seconds to remind
the front passenger to buckle their safety belt.
This only occurs if the passenger airbag is enabled.
SeePassenger Sensing System on page 1-59for more
information. The passenger safety belt light, located
on the instrument panel, comes on and stays on for
several seconds and then ashes for several more.
This chime and light are
repeated if the passenger
remains unbuckled and
the vehicle is in motion.
If the passenger safety belt is buckled, neither the
chime nor the light comes on.
Airbag Readiness Light
The system checks the airbag’s electrical system for
possible malfunctions. If the light stays on it indicates
there is an electrical problem. The system check includes
the airbag sensor, the pretensioners, the airbag modules,
the wiring and the crash sensing and diagnostic module.
For more information on the airbag system, seeAirbag
System on page 1-51.
The airbag readiness light
ashes for a few seconds
when the engine is
started. If the light does
not come on then, have
it xed immediately.
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{CAUTION:
If the airbag readiness light in the instrument panel
cluster ever comes on and stays on, it means that
something may be wrong with the airbag system.
If this ever happens, have the vehicle serviced
promptly, because an adult-size person sitting in
the right front passenger’s seat may not have the
protection of the airbag(s). SeeAirbag Readiness
Light on page 3-58for more on this, including
important safety information.
Charging System Light
This light comes on briey
when the ignition key is
turned to START, 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/retailer.
The light should go out once the engine starts. If it stays
on, or comes on while driving, there could be a problem
with the charging system. A charging system message
in the Driver Information Center (DIC) can also appear.
SeeDIC Warnings and Messages on page 3-79for more
information. This light could indicate that there are
problems with a generator drive belt, or that there is an
electrical problem. Have it checked right away. If the
vehicle must be driven a short distance with the light
on, turn off accessories, such as the radio and air
conditioner.
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