2008 CADILLAC DTS cooling

The rear doors on your vehicle cannot be opened from
the inside when this feature is in use.
When you want to open a rear door when the security
lock is on, do the following:
1. Unlock the door using the remote keyless entry
transmitter, the front door power lock switch, or
by lifting the rear door manual lock knob.
2. Open the door from the outside.
To cancel the rear door security lock, do the following:
1. Unlock the door and open it from the outside.
2. Turn the knob to the horizontal position to
disengage the lock.
3. Do the same for the other rear door.
Lockout Protection
If the key is in the ignition and the power door lock
switch is used to lock the doors, all doors will lock
and then the driver’s door will unlock. It is always
recommended that you remove the ignition key when
locking your vehicle.
The lockout protection feature can be overridden by
holding the power door lock switch for three seconds or
longer.
Trunk
{CAUTION:
It can be dangerous to drive with the trunk lid
open because carbon monoxide (CO) gas can
come into your vehicle. You cannot see or
smell CO. It can cause unconsciousness and
even death. If you must drive with the trunk lid
open or if electrical wiring or other cable
connections must pass through the seal
between the body and the trunk lid:
Make sure all other windows are shut.
Turn the fan on your heating or cooling
system to its highest speed and select the
control setting that will force outside air
into your vehicle. See Climate Control
System.
If you have air outlets on or under the
instrument panel, open them all the way.
SeeEngine Exhaust on page 2-34.
2-12

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.
3-38

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.
3-39

Analog Clock
The analog clock is located on the instrument
panel above the radio. The clock is not connected
with any other vehicle system and runs by itself.
To adjust the clock:
1. Locate the adjustment button directly below the
clock face.
2. Push and hold the adjustment button to advance
the clock hands. Holding the button down will
cause the clock to advance faster. Release the
button before reaching the desired time.
3. Push and release the button to increase the
time by one minute increments until the desired
time is reached.
Climate Controls
Dual Climate Control System
The heating, cooling, and ventilation for the vehicle
can be controlled with this system. To avoid window
fogging on rainy and humid days at temperatures above
freezing, run the air conditioning. Also, it is best to avoid
the use of recirculation mode except when maximum
air conditioning performance is needed for a short
amount of time to avoid exterior odors and fogging.Dual Climate Control System
Dual Climate Control System for Vehicles
with Rear Climate Control
3-42

Lane Departure Warning Light
Your vehicle may have the
lane departure warning
system.
This light will come on green, briey, when the vehicle
is started to show that it is working. This light will
also come on green if the system detects a left or
right lane marking. This light will change to amber
and ash and three beeps will sound if you cross a
detected lane marking without using your turn signal.
For more information, see the Index in the Navigation
Manual.
Engine Coolant Temperature
Warning Light
The engine coolant
temperature warning light
will come on when the
engine is very hot.
This light will also come on briey when the vehicle is
started.
If the light does not go out or comes on and stays on
while driving, there may be a problem with the cooling
system. Driving with engine coolant temperature light on
could cause your vehicle to overheat, seeOverheated
Engine Protection Operating Mode on page 5-29.
SeeEngine Overheating on page 5-27andDIC
Warnings and Messages on page 3-75for more
information.
3-63

Engine Coolant Temperature Gage
This gage shows the
engine coolant
temperature.
It indicates when the engine has warmed up and if
the cooling system is operating properly. If the gage
pointer moves into the shaded area, the engine coolant
is too hot and the engine coolant temperature warning
light will come on. SeeEngine Overheating on
page 5-27for more information.
Tire Pressure Light
This light comes on briey
when the engine is started.
This light will also come on when one or more of your
tires are signicantly underinated.
A tire pressure message in the Driver Information
Center (DIC), may accompany the light. SeeDIC
Warnings and Messages on page 3-75for more
information.
Stop and check your tires as soon as it is safe to
do so. If underinated, inate to the proper pressure.
SeeTires on page 5-52for more information.
If a problem is detected with the Tire Pressure Monitor
System, this light will ash for approximately 60 seconds
and then stay on solid for the remainder of the ignition
cycle. SeeTire Pressure Monitor System on page 5-63
for more information.
3-64

Hill and Mountain Roads
Driving on steep hills or through mountains is different
than driving on at or rolling terrain. Tips for driving
in these conditions include:
Keep your vehicle serviced and in good shape.
Check all uid levels and brakes, tires, cooling
system, and transmission.
Going down steep or long hills, shift to a
lower gear.
{CAUTION:
If you do not shift down, the brakes could get
so hot that they would not work well. You
would then have poor braking or even none
going down a hill. You could crash. Shift down
to let the engine assist the brakes on a steep
downhill slope.
{CAUTION:
Coasting downhill in NEUTRAL (N) or with the
ignition off is dangerous. The brakes will have
to do all the work of slowing down and they
could get so hot that they would not work well.
You would then have poor braking or even
none going down a hill. You could crash.
Always have the engine running and your
vehicle in gear when you go downhill.
Stay in your own lane. Do not swing wide or cut
across the center of the road. Drive at speeds
that let you stay in your own lane.
Top of hills: Be alert — something could be in your
lane (stalled car, accident).
Pay attention to special road signs (falling rocks
area, winding roads, long grades, passing or
no-passing zones) and take appropriate action.
4-15

When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
Start your engine,
Shift into a gear, and
Make sure the parking brake has released.
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
Your vehicle will need service more often when you are
pulling a trailer. See the Maintenance Schedule for
more on this. Things that are especially important in
trailer operation are automatic transmission uid (do not
overll), engine oil, drive belt, cooling system and
brake system. Each of these is covered in this manual,
and the Index will help you nd them quickly. If you
are trailering, it is a good idea to review this information
before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Engine Cooling When Trailer Towing
Your cooling system may temporarily overheat during
severe operating conditions. SeeEngine Overheating on
page 5-27.
4-33