1998 Mercury Grand Marquis Owner's Manuals

The defroster turns off automatically after 10 minutes or when the
ignition is turned to the OFF position. To manually turn off the defroster
before ten minutes have passed, push the control again.
CLIMATE CONTROL SYSTEM
Manual heating and air conditioning system (if equipped)
Fan speed control
Controls the volume of air circulated
in the vehicle.
Temperature control knob
Controls the temperature of the
airflow inside the vehicle.
Mode selector control
Controls the direction of the airflow
to the inside of the vehicle.
The air conditioning compressor will operate in all modes except VENT
and FLR. However, the air conditioning will only function if the outside
temperature is about 10ÉC (50ÉF) or above.
Since the air conditioner removes considerable moisture from the air
during operation, it is normal if clear water drips on the ground under
the air conditioner drain while the system is working and even after you
have stopped the vehicle.
LO
HIOFF
MIX VENTFLOOR
MAX
A/C NORM
A/C
LO
HI
OFF
MIX VENTFLOOR
MAX
A/C NORM
A/C
Controls and features
25

Under normal conditions, your vehicle's climate control system should be
left in any position other than MAX A/C or OFF when the vehicle is
parked. This allows the vehicle to ªbreatheº through the outside air inlet
duct.
²MAX A/C-Uses recirculated air to cool the vehicle. MAX A/C is noisier
than NORM A/C but more economical and will cool the inside of the
vehicle faster. Airflow will be from the instrument panel registers. This
mode can also be used to prevent undesirable odors from entering the
vehicle.
²NORM A/C-Uses outside air to cool the vehicle. It is quieter than MAX
A/C but not as economical. Airflow will be from the instrument panel
registers.
²VENT-Distributes outside air through the instrument panel registers.
However, the air will not be cooled below the outside temperature
because the air conditioning does not operate in this mode.
²OFF-Outside air is shut out and the fan will not operate. For short
periods of time only, use this mode to prevent undesirable odors from
entering the vehicle.
²FLR -Allows for maximum heating by distributing outside air through
the floor ducts. However, the air will not be cooled below the outside
temperature because the air conditioning does not operate in this
mode.
²MIX -Distributes outside air through the windshield defroster ducts
and the floor ducts. Heating and air conditioning capabilities are
provided in this mode. For added customer comfort, when the
temperature control knob is anywhere in between the full hot and full
cold positions, the air distributed through the floor ducts will be
slightly warmer than the air sent to the windshield defroster ducts. If
the temperature is about 10ÉC (50ÉF) or higher, the air conditioner
will automatically dehumidify the air to prevent fogging.
²
-Distributes outside air through the windshield defroster ducts. It
can be used to clear ice or fog from the windshield. If the temperature
is about 10ÉC (50ÉF) or higher, the air conditioner will automatically
dehumidify the air to prevent fogging.
Operating tips
²In humid weather, selectbefore driving. This will prevent your
windshield from fogging. After a few minutes, select any desired
position.
Controls and features
26

²To prevent humidity buildup inside the vehicle, don't drive with the
climate control system in the OFF position.
²Don't put objects under the front seat that will interfere with the
airflow to the back seats.
²Remove any snow, ice or leaves
from the air intake area (at the
bottom of the windshield).
²If your vehicle has been parked with the windows closed during hot
weather, the air conditioner will do a much faster job of cooling if you
drive for two or three minutes with the windows open. This will force
most of the hot, stale air out of the vehicle. Then operate your air
conditioner as you would normally.
²When placing objects on top of your instrument panel, be careful to
not place them over the defroster outlets. These objects can block
airflow and reduce your ability to see through your windshield. Also,
avoid placing small objects on top of your instrument panel. These
objects can fall down into the defroster outlets and block airflow and
possibly damage your climate control system.
Electronic Automatic Temperature Control (EATC) system
(if equipped)
The EATC system will maintain a
selected temperature and
automatically control airflow. You
can override automatic operation
with any of the override controls or
the fan speed control.
NORM A/CVENT FLOOR FLR • DEF DEF
HI
LO
MAX A/C
OUTSIDE TEMP AUTOMATICOFF
FAUTO
Controls and features
27

Turning the EATC on
Press AUTOMATIC, any of the
override controls or the fan speed
control. The EATC will only operate
when the ignition is in the ON
position.
Turning the EATC off
Press OFF. The Outside
Temperature function will continue
to operate until the ignition is
turned off.
Automatic operation
Press AUTOMATIC and select the desired temperature. The selected
temperature and the word AUTO will appear in the display window. The
EATC system will either heat or cool to achieve the selected
temperature. The system will automatically determine fan speed, airflow
location and if fresh outside air or recirculated air is required. Fan speed
remains automatic unless the fan speed thumbwheel is turned.
When in AUTOMATIC and weather conditions require heat, air will be
sent to the floor. However, if the engine is not warm enough to provide
heat, the fan will be at a low speed and the air will be directed to the
windshield. In 3ó minutes or less, the fan speed will start to increase
and the airflow location will change to the floor area.
If unusual conditions exist (i.e.-window fogging, etc.), the manual
override controls allow you to select airflow locations and the fan control
allows you to adjust fan speed as necessary.
NORM A/CVENT FLOOR FLR • DEF DEF
HI
LO
MAX A/C
OUTSIDE TEMP AUTOMATICOFF
FAUTO
FLR • DEFDEF
HI
LO
AUTOMATICOFF
Controls and features
28

Temperature selection
The display window indicates the
selected temperature, function
(AUTO or one of the override
controls) and manual control of fan
speed (
) if automatic fan speed is not desired.
To control the temperature, select
any temperature between 18ÉC
(65ÉF) and 29ÉC (85ÉF) by pressing
the blue (cooler) or red (warmer)
buttons.
For continuous maximum cooling, push the blue button until 16ÉC
(60ÉF) is shown in the display window. The EATC will continue
maximum cooling (disregarding the displayed temperature) until a
warmer temperature is selected by pressing the red button.
For continuous maximum heating, push the red button until 32ÉC (90ÉF)
is shown in the display window. The EATC will continue maximum
heating (disregarding the displayed temperature) until a cooler
temperature is selected by pressing the blue button.
Temperature conversion
Press MAX A/C and DEFat the
same time (for one second) to
switch between Fahrenheit and
Celsius.
If your vehicle has an English/Metric (E/M) control to change your
electronic instrument cluster display (if equipped) and the message
center display (if equipped) from English to Metric, this control will also
change the temperature display. Refer toElectronic Message Centerin
theInstrumentation Chapter.
˚F
AUTO
NORM A/CVENTMAX A/C
OUTSIDE TEMP
NORM A/CVENT FLOOR FLR • DEF DEF
HI
LO
MAX A/C
OUTSIDE TEMP AUTOMATICOFFAUTO
Controls and features
29

Fan speed ()
When AUTOMATIC is pressed, fan
speed is adjusted automatically for
existing conditions. You can override
fan speed at any time. To control
fan speed manually, use the
thumbwheel to cancel automatic fan
speed operation. Rotate the
thumbwheel up for higher fan speed
or down for lower fan speed.
The display will show
to indicate
manual fan operation.
To return to automatic fan operation, press AUTOMATIC.
Manual override controls
The override controls are located at
the bottom of the EATC and allow
you to determine where airflow is
directed. To return to full automatic
control, press AUTOMATIC.
The air conditioning compressor will operate in all modes except FLOOR
and VENT. It will also operate only when required when AUTOMATIC
has been selected. However, the air conditioning will only function if the
outside temperature is about 10ÉC (50ÉF) or above.
Since the air conditioner removes considerable moisture from the air
during operation, it is normal if clear water drips on the ground under
the air conditioner drain while the system is working and even after you
have stopped the vehicle.
Under normal conditions, your vehicle's climate control system should be
left in any position other than MAX A/C or OFF when the vehicle is
parked. This allows the vehicle to ªbreatheº through the outside air inlet
duct.
FLR • DEFDEF
HI
LO
AUTOMATICOFF
˚F
AUTO
NORM A/CVENT FLOOR FLR • DEF DEF
HI
LO
MAX A/C
OUTSIDE TEMP AUTOMATICOFF
FAUTO
Controls and features
30

²MAX A/C-Uses recirculated air to cool the vehicle. The temperature
display will remain the same and air will be cooled based on the
selected temperature. To exit, press AUTOMATIC or any other
override controls. MAX A/C is noisier than NORM A/C but more
economical and will cool the inside of the vehicle faster. Airflow is
from the instrument panel registers. This mode can also be used to
prevent undesirable odors from entering the vehicle.
²NORM A/C-Uses outside air to cool the vehicle. The temperature
display will remain the same and air will be cooled based on the
selected temperature. It is quieter than MAX A/C but not as
economical. Fan speed will remain automatic. Airflow is from the
instrument panel registers.
²VENT-Distributes outside air through the instrument panel registers.
However, the air cannot be cooled below the outside temperature
because the air conditioning does not operate in this mode.
²FLOOR -Allows for maximum heating by distributing outside air
through the floor ducts. However, the air cannot be cooled below the
outside temperature because the air conditioning does not operate in
this mode.
²FLR²DEF-Distributes outside air through the windshield defroster
ducts and the floor ducts. Heating and air conditioning capabilities are
provided in this mode. The air will be heated or cooled based on the
temperature selection. For added customer comfort, the air
distributed through the floor ducts will be slightly warmer than the air
sent to the windshield defroster ducts. If the temperature is about
10ÉC (50ÉF) or higher, the air conditioner will automatically
dehumidify the air to prevent fogging.
²DEF
-Distributes outside air through the windshield defroster
ducts. It can be used to clear ice or fog from the windshield. If the
outside air temperature is about 10ÉC (50ÉF) or higher, the air
conditioner will automatically dehumidify the air to prevent fogging.
²OFF-Outside air is shut out and the fan will not operate. For short
periods of time, use this mode to prevent undesirable odors from
entering the vehicle. For short periods of time only, use this mode to
prevent undesirable odors from entering the vehicle.
Controls and features
31

Displaying outside temperature
Press OUTSIDE TEMP to display
the outside air temperature. It will
be displayed until OUTSIDE TEMP
is pressed again.
If the selected temperature is changed while the outside temperature is
displayed, the new temperature will be displayed for four seconds after it
is changed, then the outside temperature will return to the window.
If a manual override function is selected while the outside temperature is
displayed, the new function will be displayed for four seconds after it is
changed, then the outside temperature will return to the window along
with the override selection.
The outside temperature reading is most accurate when the vehicle is
moving. Higher readings may be obtained when the vehicle is not
moving. The readings that you get may not agree with temperatures
given on the radio due to differences in vehicle and station locations.
Operating tips
²In humid weather, select DEFbefore driving. This will prevent
your windshield from fogging. After a few minutes, select any desired
position.
²To prevent humidity buildup inside the vehicle, don't drive with the
climate control system in the OFF position.
²Don't put objects under the front seat that will interfere with the
airflow to the back seats.
NORM A/CVENTMAX A/C
OUTSIDE TEMP
Controls and features
32