2008 CADILLAC DTS light

When DRL are on, no other exterior lamps such as the
parking lamps, taillamps, etc. will be on when the DRL
are being used. The instrument panel will not be lit up
either.
When automatic lighting is on and it is dark enough
outside, the turn signal lamps turn off and normal
low-beam headlamp operation occurs.
When automatic lighting is on and it is bright enough
outside, the regular lamps go off, and the DRL takes over.
If the vehicle is started in a dark garage, the automatic
headlamp system comes on immediately. Once you
leave the garage, it will take approximately one minute for
the automatic headlamp system to change to DRL if there
is light outside. During that delay, the instrument panel
cluster may not be as bright as usual. Make sure the
instrument panel brightness knob is in the full bright
position. SeeInstrument Panel Brightness on page 3-37.
Turning on automatic lighting or the headlamps will
deactivate the DRL. If the parking lamps or the
fog lamps were turned on instead, the DRL will still
deactivate.
To idle the vehicle with the DRL off at night, turn off
automatic lighting and shift the transmission into
PARK (P). Placing the vehicle in PARK (P) disables the
DRL. The DRL will stay off until the vehicle is shifted
out of PARK (P).To drive the vehicle with the DRL off, turn off automatic
lighting and manually turn on the parking lamps or
fog lamps, if the vehicle has them.
As with any vehicle, the regular headlamp system
should be turned on when needed.
Fog Lamps
Use the fog lamps for better vision in foggy or misty
conditions.
-(Fog Lamps):The fog lamps button is located on
the exterior lamps control. The exterior lamps control
is located on the instrument panel to the left of the
steering column.
The ignition must be on for the fog lamps to work.
Press the exterior lamps button to turn the fog lamps
on or off. A light will come on in the instrument
panel cluster when the fog lamps are in use.
When the headlamps are changed to high-beam,
the fog lamps will turn off. The fog lamps come back
on again when the high-beam headlamps are turned off.
Some localities have laws that require the headlamps
to be on along with the fog lamps.
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Cornering Lamps
The cornering lamps come on when the headlamps or
parking lamps are on and you signal a turn with the
multifunction lever. They provide more light for
cornering.
Exterior Lighting Battery Saver
If the exterior lamp button has been left on, the exterior
lamps will turn off about 10 minutes after the ignition is
turned to LOCK/OFF and a door has been opened. This
protects against draining the battery if the headlamps or
parking lamps are accidentally left on. If you need to
leave the lamps on for more than 10 minutes, use the
exterior lamp control to turn the lamps back on after the
ignition is turned to LOCK/OFF and any door is opened.
Instrument Panel Brightness
D(Instrument Panel Brightness):This feature
controls the brightness of the instrument panel and
footwell lights, if equipped.
The button for this control is located below the exterior
lamps control.
Push the button in and release to extend the button.
Turn the button clockwise or counterclockwise to
brighten or dim the lights.
Courtesy Lamps
The courtesy lamps are located on the headliner above
the rear seat. These lamps come on by turning the
instrument panel brightness knob fully clockwise or when
any door is opened and it is dark outside. Puddle
lamps are located on the bottom of the front and rear
door trim.
Professional vehicles have an additional dome lamp and
also opera lamps.
Entry Lighting
This feature turns on the courtesy lamps and the
backlighting for the door switches and the exterior
lamp control when a door is opened or if the remote
keyless entry transmitter unlock button is pressed.
If activated due to the transmitter, the lighting remains
active for about 40 seconds. Since the entry lighting
system uses the light sensor, it must be dark outside in
order for the courtesy lamps to turn on. The courtesy
lamps turn off approximately 25 seconds after the
last door is closed. They will dim to off if the ignition
key is turned to ON/RUN, or immediately deactivate if
the power locks are activated.
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Parade Dimming
This feature prohibits dimming of the digital displays and
backlighting during daylight hours when the key is in
the ignition and the headlamps are on. This feature is
fully automatic. When the light sensor reads darkness
outside and the parking lamps are active, the digital
displays can be adjusted by turning the instrument panel
brightness knob counterclockwise to dim and clockwise
to brighten lighting.
Reading Lamps
The reading lamps are located on the overhead console
on the headliner and in the rear door opening. These
lamps come on automatically when any door is opened
and it is dark outside.
For manual operation, press the button to turn them on.
Press it again to turn them off.
If the reading lamps are left on, they automatically shut
off 10 minutes after the ignition has been turned off.
Footwell Lamps
If your vehicle has footwell lamps, they are located
under the instrument panel and at the rear of the front
seats. These lamps provide soft light to the front
and rear oor areas. They dim with the instrument panel
cluster lights, before going out completely.
Footwell lighting brightness can be adjusted with the
instrument panel brightness control located below
the exterior lamps control. SeeInstrument Panel
Brightness on page 3-37. The footwell lights will turn off
before the instrument panel lights are at their lowest
level of brightness.
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.
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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, the heated seats may not get as warm
as they usually do and the climate control fan may cut
back to a lower speed. For more battery saving
information, see “Battery Saver Active Message” under
DIC Warnings and Messages on page 3-75.
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 put the charge back in. 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 loads 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 3-75.
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Automatic Operation
AUTO9(Automatic Fan):When this position is
selected on the fan control, the system adjusts the fan
speed. If the OnStar
®system is activated when this
position is selected, the climate control fan speed
will lower.
AUTO (Automatic Mode):
1. Turn the fan control to the AUTO position.
2. Turn the mode control to the AUTO position.
3. Adjust the temperature to a comfortable setting
between 68°F (21°C) and 78°F (26°C).
Choosing the coldest or warmest temperature
setting will not cause the system to heat or cool any
faster. In cold weather, the system will start at
reduced fan speeds to avoid blowing cold air into
the vehicle until warmer air is available. The system
starts out blowing air at the oor but may change
modes automatically as the vehicle warms up
to maintain the chosen temperature setting. The
length of time needed to warm the interior depends
on the outside temperature and temperature of
the vehicle.
4. Wait 20 to 30 minutes for the system to stabilize in
order for the system to regulate automatically. Then
adjust the temperature as necessary to nd your
comfort setting.Do not cover the solar sensor located in the center of
the instrument panel near the windshield. For more
information on the solar sensor, see “Sensors” later in
this section.
After the vehicle is started, the display will show the
interior temperature settings and the outside
temperature.
If the AUTO position is selected on the fan or mode
control, the system automatically controls the air
conditioning compressor. The A/C compressor will run
automatically even at cool outside temperatures in order
to dehumidify the air. The A/C indicator light is lit
when the system is operating automatically, even at
near freezing outside temperatures. Press the A/C
button on the fan control to turn off the A/C. For
improved window clearing performance in defog or
defrost modes, the A/C compressor runs automatically.
h(AUTO RECIRCULATION):If the AUTO position is
selected on either the fan or mode control, the system
automatically controls the air inlet to supply fresh outside
air or recirculate the interior air to cool the car faster.
The indicator light on the recirculation button will light
whenever the system switches to recirculation. You may
force outside air by pressing the recirculation button when
the light is lit. For vehicles without rear climate controls,
press the outside air button to force outside air. The next
time AUTO fan or mode is selected, the air inlet will reset
back to AUTO operation.
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Manual Operation
9(Fan):Turn the left control knob clockwise or
counterclockwise to adjust the fan speed. Turning this
control completely counterclockwise will turn on the
automatic fan operation. Turning this control to the
“O” position will turn the climate control system off.
If the airow seems low when the fan speed is at the
highest setting, the passenger compartment air lter
may need to be replaced. SeePassenger Compartment
Air Filter on page 3-51.
9(Off):Turn the left control knob to this position to
turn the entire climate control system off. Outside air
still enters the vehicle and is directed to the oor.
The airow direction and temperature can be adjusted,
as indicated below.
If the temperature is adjusted while the system is off,
the display will light to show the current settings.
Mode Control:Turn the right knob clockwise or
counterclockwise to change the current airow mode.
AUTO:Turn the control to this position to turn on
the automatic delivery mode operation.
F(Vent):Turn the control to this mode to direct air to
the instrument panel outlets.
*(Bi-Level):Turn the control to this mode to direct
approximately half of the air to the instrument panel
outlets and most of the remaining air to the oor outlets.
In automatic operation, cooler air is directed to the
upper outlets and warmer air to the oor outlets.
7(Floor):Turn the control to this mode to direct most
of the air to the oor outlets with some air directed to
the side window outlets and the windshield.
If recirculation is selected, it only stays on for
three minutes to reduce windshield fogging.
The mode control can also be used to select the oor/
defog mode. In this mode, the system automatically
uses outside air. Information on defogging and
defrosting can be found later in this section.
:(Outside Air):Press this button to allow outside
air to come into the vehicle. Press this button to turn the
outside air mode on or off. When the button is pressed,
the indicator light comes on. Pressing the recirculation
button will cancel this mode.
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?(Recirculation):Press this button to recirculate
cabin air through the vehicle. An indicator light below the
button comes on to show that this mode is activated.
This mode can be used to prevent outside air and odors
from entering the vehicle or to help cool the air inside
the vehicle more quickly. This mode cannot be selected
while in the defog or defrost modes. If you try to
select the recirculation mode, the indicator light ashes
three times and turns off.
Operation in this mode during periods of high humidity
and cool outside temperatures may result in increased
window fogging. If window fogging is experienced, select
the defrost mode.
wx(Driver’s Temperature Controls):Press these
buttons next to the fan control to manually increase
or decrease the temperature inside the vehicle.
wx(Passenger’s Temperature Controls):Press
these buttons next to the mode control to manually
increase or decrease the temperature for the front
passenger. If the passenger’s climate control system is
off, pressing one of these buttons turns it on.PASS (Passenger’s Climate Control):Press this
button to turn the passenger’s climate control systems
on or off. When the passenger’s climate control
system is on, the passenger’s temperature setting is
displayed. The temperature selected by the front
passenger also controls the rear system air temperature
unless the rear seat passengers select their own
comfort setting.
If the PASS button is pressed to turn the passenger
temperature setting off, the driver’s temperature
knob will control the temperature for the entire vehicle.
AUX:If your vehicle has a rear climate control
system, press this button to turn the rear climate control
fan on for automatic operation. After the AUX button
is pressed, the indicator light comes on. Press the button
again to turn the auxiliary fan off. SeeRear Climate
Control System on page 3-49.#(Air Conditioning):Press the center of the left
control knob to override the automatic system and turn
the air conditioning system on or off. When in AUTO,
the air conditioning compressor comes on automatically,
as necessary.
The air conditioning system removes moisture from the
air, so a small amount of water may drip underneath
the vehicle while idling or after turning off the engine.
This is normal.
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In order to prevent false temperature readings at
startup, the displayed temperature will not change
until the following occurs:
Vehicle speed is above 10 mph (16 km/h)
for 5 minutes.
Vehicle speed is above 32 mph (51 km/h)
for 2 and a half minutes.
The climate control system uses the information from
these sensors to maintain your comfort setting by
adjusting the outlet temperature, fan speed, and the
air delivery mode. The system may also supply cooler
air to the side of the vehicle facing the sun. The
recirculation mode will also be used as needed to
maintain cool outlet temperatures.
Defogging and Defrosting
Fog on the inside of windows is a result of high humidity
(moisture) condensing on the cool window glass.
This can be minimized if the climate control system
is used properly. There are two modes to clear fog
from your windshield. Use the oor/defog mode to
clear the windows of fog or moisture and warm
the passengers. Use the defrost mode to remove
fog or frost from the windshield more quickly.
W(Floor/Defog):Turn the control to this mode to
direct approximately half of the air to the oor outlets
and the remaining air is directed to the side window
outlets and to the windshield. When you select
this mode, the system turns off recirculation and runs
the air conditioning compressor unless the outside
temperature is at or below freezing. The recirculation
mode cannot be selected while in the oor/defog mode.
0(Defrost):Turn the control to this mode to direct
most of the air to the windshield and the side window
outlets. In this mode, the system automatically turns off
recirculation and runs the air conditioning compressor,
unless the outside temperature is at or below freezing.
Recirculation cannot be selected while in the defrost
mode. Do not drive the vehicle until all the windows
are clear.
For professional vehicles, air will be allowed to ow
through the rear outlets. For quicker defrost, press the
AUX button on the front climate control system so
that the light is not lit.
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