2009 CADILLAC STS headlamp

Wiper Activated Headlamps
This feature activates the headlamps and parking lamps
after the windshield wipers have been in use for about
six seconds. For this feature to work, automatic lighting
must be enabled. SeeHeadlamps on page 3-32for
additional information.
When the ignition is turned off, the wiper-activated
headlamps will immediately turn off. They will also
turn off if the windshield wiper control is turned off.
Headlamps on Reminder
A warning chime will sound if the exterior lamp control
is left on in either the headlamp or parking lamp position
and the driver’s door is opened with the ignition off.
SeeLights On Reminder on page 3-70for additional
information.
Daytime Running Lamps (DRL)
Daytime Running Lamps (DRL) can make it easier for
others to see the front of your vehicle during the day.
Fully functional daytime running lamps are required
on all vehicles rst sold in Canada.The DRL system comes on when the following
conditions are met:
It is still daylight and the ignition is on.
The automatic lights are enabled.
The transmission is not in P (Park).
When DRL are on, only the front turn signal lamps will
be on. No other exterior lamps will be on when the DRL
are being used. The instrument panel will not be lit.
When the automatic lights are enabled and it is dark
enough outside, the DRL will turn off and the low-beam
headlamps will turn on. When it is bright enough outside,
the low-beam headlamps will go off, and the DRL will turn
back on. If the vehicle is started in a dark garage, the
automatic headlamp system comes on immediately.
Once the vehicle leaves the garage, it will take about
one minute for the automatic headlamp system to
change to DRL if it is light outside. During that delay,
the instrument panel cluster may not be as bright as
usual. Make sure the instrument panel brightness lever
is in the full bright position. SeeInstrument Panel
Brightness on page 3-40.
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To operate the vehicle with the DRL off, turn the
exterior lamp control off and then do one of the
following:
Turn the exterior lamp control to the parking lamp
position.
Turn the exterior lamp control to the headlamp
position.
Turn the exterior lamp control from AUTO to off and
back to AUTO.
An AUTOMATIC LIGHTS OFF message will appear
on the DIC, showing that automatic lighting has
been disabled. SeeDIC Warnings and Messages
on page 3-79.
The regular headlamp system should be turned on
when needed.
Light Sensor
The light sensor for the DRL is located on top of the
instrument panel. If the sensor is covered, it will prevent it
from sensing light, and the exterior lamps may come on
when they are not needed.
3-37

Fog Lamps
The fog lamp controls are located on the turn
signal/multifunction lever.
#(Fog Lamps):The band with this symbol is used to
turn the fog lamps on and off.
The parking lamps must be on for the fog lamps
to work.
To turn the fog lamps on or off, turn the fog lamp band
on the lever up to the dot and release it. The band
will return to its original position.
If the high-beam headlamps are turned on, the fog
lamps will turn off. The fog lamps will come back
on when the high-beam headlamps are off.
Some localities have laws that require the headlamps to
be on along with the fog lamps.
Twilight Sentinel®
Twilight Sentinel®can turn the lamps on and off for you.
A light sensor on top of the instrument panel makes the
Twilight Sentinel work, so be sure it is not covered.
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With Twilight Sentinel the following will happen:
When it is dark enough outside, the front turn signal
lamps (DRL) will go off, and the headlamps and
parking lamps will come on. The other lamps
that come on with headlamps will also come on.
When it is bright enough outside, the headlamps
will go off, and the front turn signal lamps (DRL)
will come on, as long as the exterior lamp switch
is in the off position.
If the vehicle is started in a dark garage, the automatic
headlamp system comes on immediately. Once the
vehicle leaves the garage, it will take about one minute
for the automatic headlamp system to change to DRL
if it is light outside. During that delay, the instrument
panel cluster might not be as bright as usual. Make sure
the instrument panel brightness control is in full bright
position. SeeInstrument Panel Brightness on page 3-40
for more information.
You can idle the vehicle with the lamps off, even when
it is dark outside. First set the parking brake while the
ignition is in OFF/ACCESSORY. Then start the vehicle.
The lamps will stay off until the parking brake is released.Twilight Sentinel also provides exterior illumination as
you leave the vehicle. If Twilight Sentinel has turned on
the lamps when you turn off the ignition, the lamps
will remain on until:
The exterior lamp switch is moved from off to the
parking lamp position.
A delay time that you select has elapsed.
SeeVehicle Personalization on page 2-61to select the
delay time needed. You can also select no delay time.
If the ignition is turned off with the exterior lamp switch
in the parking lamp or headlamp position, the Twilight
Sentinel delay will not occur. The lamps will turn off
as soon as the switch is turned off.
As with any vehicle, the regular headlamp system
should be turned on when needed.
3-39

Exterior Lighting Battery Saver
If the parking lamps or headlamps have been left on,
the exterior lamps will turn off about 10 minutes after the
ignition is turned off. This protects against draining the
battery in case you have accidentally left the headlamps
or parking lamps on. The battery saver does not work
if the headlamps are turned on after the ignition is
turned off.
If you need to leave the lamps on for more than
10 minutes, use the exterior lamp control to turn
the lamps back on.
Instrument Panel Brightness
Press the center knob on
the DIC control panel to
extend. Then turn the knob
clockwise to brighten the
lights or counterclockwise
to dim them. If the knob
is turned completely
clockwise, the interior
lamps turn on.
Base Level Shown,
Uplevel Similar
3-40

Entry Lighting
The entry lighting system turns on the reading and
dome lamps and the backlighting to the exterior lamp
control when a door is opened or if you press the remote
keyless entry transmitter unlock button. If activated by
the transmitter, the lighting will remain active for about
25 seconds. The entry lighting system uses the light
sensor; it must be dark outside in order for the lamps to
turn on. The lamps turn off about 25 seconds after the
last door is closed. They will dim to off if the ignition is
on, or immediately deactivate if the power locks are
activated.
Parade Dimming
This feature prohibits dimming of the instrument panel
displays and backlighting during daylight hours when
the key is in the ignition and the headlamps are on.
This feature operates with the light sensor and is fully
automatic. When the light sensor reads darkness outside
and the parking lamps are active, the instrument panel
displays can be adjusted by turning the instrument panel
brightness knob. SeeInstrument Panel Brightness on
page 3-40for additional information.
Reading Lamps
The reading lamps are located on the overhead console.
These lamps come on automatically when any door is
opened.
For manual operation, press the button next to each
lamp to turn it on or off.
If the reading lamps are left on, they automatically shut
off 10 minutes after the ignition has been turned off.
Battery Load Management
The battery load management feature is designed to
monitor the vehicle’s electrical load and determine when
the battery is in a heavy discharge condition. During
times of high electrical loading, the engine may idle at a
higher revolutions per minute (rpm) setting than normal to
make sure the battery charges. High electrical loads may
occur when several of the following are on: headlamps,
high beams, fog lamps, rear window defogger, the
climate control fan at high speeds, heated seats and
engine cooling fans.
If the battery continues to discharge, even with the
engine idling at a higher rpm setting, some electrical
loads will automatically be reduced. When this occurs,
the rear window defogger may take slightly longer to clear
the glass and the fan may cut back to a lower speed.
For more battery saving information, see “Battery Saver
Active Message” underDIC Warnings and Messages on
page 3-79.
3-41

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.
3-42

Fog Lamp Light
The fog lamp light comes
on when the fog lamps are
in use.
The light goes out when the fog lamps are turned off.
SeeFog Lamps on page 3-38for more information.
Lights On Reminder
This light comes on
whenever the parking
lamps are on.
SeeHeadlamps on Reminder on page 3-36for more
information.
Cruise Control Light
This light comes on
whenever the cruise
control is set.
The light goes out when the cruise control is turned off.
SeeCruise Control on page 3-16andAdaptive Cruise
Control on page 3-20for more information.
Highbeam On Light
This light comes on when
the high-beam headlamps
are in use.
SeeHeadlamp High/Low-Beam Changer on page 3-9
for more information.
3-70