engine coolant CADILLAC DEVILLE 1999 7.G User Guide

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Manual Operation
RECIRCULATION: Press this button to limit the
amount of fresh air entering your vehicle. This is helpful
when you are trying to cool the air quickly or limit odors
entering your vehicle. In the AUTO mode, the system
will use recirculation as necessary to cool the air.
Pressing the recirculation button will change the
operation to a manual mode and the air will recirculate
non
-stop. Press this button again to turn off the
recirculation feature.
If you notice the windows fogging, press the
recirculation button to exit the recirculation mode.
OFF: Press this button to turn the system off. Fresh air
will continue to flow through the vehicle, and the
system will try to maintain the previously set
temperature. The outside temperature will show in the
display when the system is off.
DEFOG: Press this button to divide the air between the
windshield and the heater outlets. This is useful when
fog appears on the windshield or side glass due to
sudden rain or snowy conditions.
AUTO/ECON: Press this button to switch between
AUTO and ECON. The ECON setting attempts to keep air
at a selected temperature, however, it does not remove
humidity from the air. Use this setting in cold or coolweather to save fuel. The AUTO setting is used when
it's warm outside and you need to cool the air in order to
maintain a selected temperature and blower speed.
FAN SPEEDS: Press the button with the fan symbol
on it until AUTO is displayed on the screen. At this
setting, the fan speed is automatically controlled. If it is
cold outside, the blower may not run in the maximum high
fan speed right away. The system checks the temperature
of the engine coolant to assure it is warm enough to
provide heat. When the engine coolant is warm, the
controller allows the fan to gradually increase to a higher
speed. This prevents cold air from blowing into the
passenger compartment. If you want the blower fan at a
high speed, press the up arrow button until you see HI on
the display. If you want the fan speed to be automatic, but
you like the fan speed to be higher than the AUTO setting,
press the fan symbol button until HI AUTO is shown on
the display. If you want the blower fan at a low speed,
press the down arrow button until LO is shown on the
display. If you want the fan speed to run lower than the
AUTO setting, press the button until AUTO LO is shown
on the display.
DEFROST: Press this button to quickly remove
fog or frost from the windshield. This setting sends most
of the airflow to the windshield with only a small
amount to the floor outlets.

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Mode Button
Press the MODE button to deliver air through the floor,
middle or windshield outlets. The system will stay in the
selected mode until the MODE button is pressed again.
Press the up or down arrow to cycle through the
available modes.
Automatic Operation
When the system is set for automatic operation, sensors
will control the air delivery mode. Air will come from
the floor, middle or windshield outlets. The fan speed
will vary as the system maintains the selected
temperature setting.
Be careful not to put anything over the solar sensor
located in the middle of the instrument panel near the
windshield. This sensor is used by the automatic system
to regulate temperature.
To find your comfort zone, start with the 75
F (24
C)
setting and allow about 30 minutes for the system to
regulate. Turn the TEMP/AUTO knob to adjust the
temperature if necessary. If you choose 60
F (16
C),
the system will remain at that maximum cooling setting
and will not regulate fan speed. If you choose the
temperature of 90
F (32
C), the system will remain at
that maximum heating setting and will not regulate fan
speed. Choosing either maximum setting will not cause
the system to heat or cool any faster.With the automatic setting, the air conditioning
compressor automatically cycles when needed to cool
the air. In cold weather, when the system senses the
need for heat, the airflow will be directed out the floor
outlets. As the interior temperature approaches a desired
setting, the blower speed will decrease. To maintain
interior comfort, the airflow may move to the instrument
panel air outlets and floor outlets (bi
-level mode). On
bright sunny days in cold weather, the airflow may come
out of the air conditioning outlets (AC mode) to
maintain comfort and prevent stuffiness.
If your vehicle is sitting out on a hot day and you have
it set on AUTO, the air will first flow out the floor air
outlets for a few seconds. That is normal. This is to
expel hot air from the air outlets. As the air is cooled,
the airflow will move through the air conditioning
outlets. If you start your vehicle with the fan setting on
HI, it will skip the air conditioning purge.
To avoid blowing cold air in cold weather, the
system will delay turning on the fan until warm air is
available. The length of delay depends on the outside
air temperature, engine coolant temperature or the
time since the engine was last started. As the coolant
warms up, the blower fan speed will gradually increase
and air will flow from the heater outlets, with some
airflow to the windshield to prevent fogging under
most normal conditions.

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If you leave your vehicle, the system will remember
the control setting the next time you start your engine,
except for recirculation and defrost. Each ignition cycle
cancels recirculation, whereas, DEFROST will change
to automatic operation when the ignition is shut off and
then turned back on.
Manual Operation
You may manually adjust the air delivery mode or
fan speed.
AC: This setting directs airflow through the middle
instrument panel outlets.
BI-LEVEL: This setting directs air into your
vehicle in two ways. Cool air is directed to the upper
portion of your body through the four instrument panel
outlets while warmed air is directed to the floor.
HEATER/DEFROST: This setting directs air to
the floor outlets and toward the windshield.
HEATER: This setting directs warmed air
through the floor outlets. Some warm air is diverted to
the windshield to minimize fogging.
DEFROST: Press this button to quickly remove
fog or frost from the windshield. This setting sends most
of the airflow to the windshield with only a small
amount to the floor outlets.
FAN SPEEDS: Press the button with the fan
symbol on it until AUTO is displayed on the screen.
At this setting, the fan speed is automatically controlled.
If it is cold outside, the blower may not run in the
maximum high fan speed right away. The system
checks the temperature of the engine coolant to assure
it is warm enough to provide heat. When the engine
coolant is warm, the controller allows the fan to
gradually increase to a higher speed. This prevents
cold air from blowing into the passenger compartment.
If you want the blower fan at a high speed, press the up
arrow button until you see HI on the display. If you want
the fan speed to be automatic, but you like the fan speed
to be higher than the AUTO setting, press the fan
symbol button until HI AUTO is shown on the display.
If you want the blower fan at a low speed, press the
down arrow button until LO is shown on the display.
If you want the fan speed to run lower than the AUTO
setting, press the button until LO AUTO is shown on
the display.

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Towing Your Vehicle
CAUTION:
To help avoid serious personal injury to you
or others:

Never let passengers ride in a vehicle that is
being towed.

Never tow faster than safe or posted speeds.

Never tow with damaged parts not
fully secured.

Never get under your vehicle after it has
been lifted by the tow truck.

Always secure the vehicle on each side with
separate safety chains when towing it.

Use only the correct hooks.
NOTICE:
Use the proper towing equipment to avoid
damage to the bumper, fascia or fog lamp areas
of the vehicle.
With current trends in automotive styles and design, it is
essential that the correct towing equipment is used to
tow a vehicle. Your vehicle can be towed with wheel
-lift
or car
-carrier equipment.
Consult your dealer or a professional towing service if
you need to have your vehicle towed. See ªRoadside
Assistanceº in the Index.
Engine Overheating
You will find an ENGINE COOLANT HOT, IDLE
ENGINE message or an ENGINE OVERHEATED,
STOP ENGINE message on the Driver Information
Center (DIC). You will also hear a chime. There is also
an engine temperature warning light and/or gage on the
instrument panel. See ªEngine Coolant Temperature
Warning Lightº or ªEngine Coolant Temperature Gageº
in the Index.

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5-9 Overheated Engine Protection
Operating Mode
Should an overheated engine condition exist and the
message ENGINE OVERHEATED, STOP ENGINE is
displayed, 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. This operating mode allows your vehicle
to be driven to a safe place in an emergency; you may
drive up to 50 miles (80 km). 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, change the oil and reset the
oil life indicator. See ªEngine Oilº in the Index.
If Steam Is Coming From Your Engine

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CAUTION:
Steam from an overheated engine can burn you
badly, even if you just open the hood. Stay away
from the engine if you see or hear steam coming
from it. Just turn it off and get everyone away
from the vehicle until it cools down. Wait until
there is no sign of steam or coolant before you
open the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch fire. You or
others could be badly burned. Stop your engine if
it overheats, and get out of the vehicle until the
engine is cool.
NOTICE:
If your engine catches fire because you keep
driving with no coolant, your vehicle can be
badly damaged. The costly repairs would not be
covered by your warranty. See ªOverheated
Engine Protection Operating Modeº in the Index.
If No Steam Is Coming From Your Engine
If you get an engine overheat warning but see or hear no
steam, the problem may not be too serious. Sometimes
the engine can get a little too hot when you:

Climb a long hill on a hot day.

Stop after high
-speed driving.

Idle for long periods in traffic.

Tow a trailer.

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If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. If your air conditioner is on, turn it off.
2. Dial temperature control to the highest heat setting
and open the windows, as necessary.
3. If you're in a traffic jam, shift to NEUTRAL (N);
otherwise, shift to the highest gear while
driving
-- OVERDRIVE (
) or THIRD (3).
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning doesn't come back on, you can
drive normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there's still no sign of steam, idle the engine for three
minutes while you're parked. If you still have the
warning, turn off the engine and get everyone out of the
vehicle until it cools down. Also, see ªOverheated
Engine Protection Operating Modeº listed previously in
this section.
You may decide not to lift the hood but to get service
help right away.
Cooling System
When you decide it's safe to lift the hood, here's what
you'll see:
A. Coolant Surge Tank with Pressure Cap
B. Electric Engine Fans

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CAUTION:
An electric engine cooling fan under the hood can
start up even when the engine is not running and
can injure you. Keep hands, clothing and tools
away from any underhood electric fan.
If the coolant inside the coolant surge tank is boiling,
don't do anything else until it cools down.
A low coolant level should be indicated by a CHECK
COOLANT LEVEL message on the Driver Information
Center. If it is, you may have a leak in the radiator
hoses, heater hoses, radiator, water pump or somewhere
else in the cooling system.
CAUTION:
Heater and radiator hoses, and other engine
parts, can be very hot. Don't touch them. If you
do, you can be burned.
Don't run the engine if there is a leak. If you run
the engine, it could lose all coolant. That could
cause an engine fire, and you could be burned.
Get any leak fixed before you drive the vehicle.

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NOTICE:
Engine damage from running your engine
without coolant isn't covered by your warranty.
See ªOverheated Engine Protection Operating
Modeº in the Index.
NOTICE:
When adding coolant, it is important that you use
only DEX
-COOL
(silicate-free) coolant.
If coolant other than DEX-COOL is added to the
system, premature engine, heater core or
radiator corrosion may result. In addition, the
engine coolant will require change sooner
-- at
30,000 miles (50 000 km) or 24 months,
whichever occurs first. Damage caused by the use
of coolant other than DEX
-COOL
is not
covered by your new vehicle warranty.
If there seems to be no leak, with the engine on, check to
see if the electric engine cooling fans are running. If the
engine is overheating, both fans should be running. If
they aren't, your vehicle needs service.
How to Add Coolant to the Coolant
Surge Tank
If you haven't found a problem yet, but the coolant level
isn't at the proper level (2.5 inches (6.4 cm) below the
base of the fill neck), add a 50/50 mixture of clean,
drinkable water and DEX
-COOL
coolant at the
coolant surge tank, but be sure the cooling system,
including the coolant surge tank pressure cap, is cool
before you do it. (See ªEngine Coolantº in the Index
for more information.)

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CAUTION:
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like alcohol, can boil before the proper
coolant mixture will. Your vehicle's coolant
warning system is set for the proper coolant
mixture. With plain water or the wrong mixture,
your engine could get too hot but you wouldn't
get the overheat warning. Your engine could
catch fire and you or others could be burned. Use
a 50/50 mixture of clean, drinkable water and
DEX
-COOL
coolant.
NOTICE:
In cold weather, water can freeze and crack the
engine, radiator, heater core and other parts. So
use the recommended coolant.
CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol
and it will burn if the engine parts are hot
enough. Don't spill coolant on a hot engine.