2021 LINCOLN NAUTILUS Owners Manual

To top up the coolant level do the following:
1. Unscrew the cap slowly. Any pressure
escapes as you unscrew the cap.
2. Add enough prediluted coolant to reach
the correct level.
Note: We do not recommend the use of
recycled coolant.
3. Replace the coolant reservoir cap. Turn the cap clockwise until it contacts the
hard stop.
4. Check the coolant level in the coolant reservoir the next few times you drive
your vehicle. If necessary, repeat step 2.
If you have to add more than 1.1 qt (1 L) of
engine coolant per month, have your vehicle
checked as soon as possible. Operating an
engine with a low level of coolant can result
in engine overheating and possible engine
damage.
In case of emergency, you can add a large
amount of water without engine coolant in
order to reach a vehicle service location.
Service your vehicle as soon as possible. Water alone, without engine coolant, can
cause engine damage from corrosion,
overheating or freezing.
Do not use the following as a coolant
substitute, as they can cause engine damage
from overheating or freezing:
•
Alcohol.
• Methanol.
• Brine.
• Any coolant mixed with alcohol or
methanol antifreeze.
Do not add extra inhibitors or additives to
the coolant. These can be harmful and
compromise the corrosion protection of the
coolant.
Severe Climates
If you drive in extremely cold climates, you
may need to increase the coolant
concentration above 50%. Note:
A coolant concentration of 60%
provides improved freeze point protection.
Coolant concentrations above 60% decrease
the overheat protection characteristics of
the coolant and could cause engine
damage.
If you drive in extremely hot climates, you
may need to decrease the coolant
concentration to 40%.
Note: Coolant concentrations below 40%
decrease the freeze and corrosion protection
characteristics of the coolant and could
cause engine damage.
Coolant Change
Change the coolant at specific mileage
intervals. Refer to the scheduled
maintenance information.
See Normal
Scheduled Maintenance (page 463).
Note: Dispose of used coolant in the
appropriate manner.
Follow your community's regulations and
standards for recycling and disposing of
automotive fluids.
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Fail-Safe Cooling
Fail-safe cooling allows you to temporarily
drive your vehicle before any incremental
component damage occurs. The fail-safe
distance depends on ambient temperature,
vehicle load and terrain.
How Fail-Safe Cooling Works
If the engine begins to overheat,
the coolant temperature gauge
moves toward the red zone:
A warning lamp illuminates and a
message may appear in the
information display.
If the engine reaches a preset
over-temperature condition, the engine
automatically switches to alternating cylinder
operation. Each disabled cylinder acts as an
air pump and cools the engine.
When this occurs, your vehicle still operates,
however:
• Engine power is limited.
• The air conditioning system turns off. Continued operation increases the engine
temperature, causing the engine to
completely shut down. Your steering and
braking effort increases in this situation.
When the engine temperature cools, you can
re-start the engine. Have your vehicle
checked as soon as possible to minimize
engine damage.
When Fail-Safe Mode Is Activated
WARNING: Fail-safe mode is for use
during emergencies only. Operate your
vehicle in fail-safe mode only as long as
necessary to bring your vehicle to rest in
a safe location and seek immediate repairs.
When in fail-safe mode, your vehicle will
have limited power, will not be able to
maintain high-speed operation, and may
completely shut down without warning,
potentially losing engine power, power
steering assist, and power brake assist,
which may increase the possibility of a
crash resulting in serious injury. WARNING: Do not remove the
coolant reservoir cap when the engine is
on or the cooling system is hot. Wait 10
minutes for the cooling system to cool
down. Cover the coolant reservoir cap with
a thick cloth to prevent the possibility of
scalding and slowly remove the cap.
Failure to follow this instruction could result
in personal injury.
Your vehicle has limited engine power when
in the fail-safe mode, drive your vehicle with
caution. Your vehicle does not maintain
high-speed operation and the engine could
operate poorly.
Remember that the engine is capable of
automatically shutting down to prevent
engine damage. In this situation:
1. Pull off the road as soon as safely possible and switch the engine off.
2. If you are a member of a roadside assistance program, we recommend that
you contact your roadside assistance
service provider.
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3. If this is not possible, wait for a short
period of time for the engine to cool.
4. Check the coolant level. If the coolant level is at or below the minimum mark,
add prediluted coolant immediately.
5. When the engine temperature cools, you
can re-start the engine. Have your vehicle
checked as soon as possible to minimize
engine damage.
Note: Driving your vehicle without repair
increases the chance of engine damage.
Engine Coolant Temperature
Management (If Equipped) WARNING:
To reduce the risk of
crash and injury, be prepared that the
vehicle speed may reduce and the vehicle
may not be able to accelerate with full
power until the coolant temperature
reduces. If you tow a trailer with your vehicle, the
engine may temporarily reach a higher
temperature during severe operating
conditions, for example ascending a long or
steep grade in high ambient temperatures.
At this time, you may notice the coolant
temperature gauge moves toward the red
zone and a message may appear in the
information display.
You may notice a reduction in vehicle speed
caused by reduced engine power in order
to manage the engine coolant temperature.
Your vehicle may enter this mode if certain
high-temperature and high-load conditions
take place. The amount of speed reduction
depends on vehicle loading, grade and
ambient temperature. If this occurs, there is
no need to stop your vehicle. You can
continue to drive.
The air conditioning may automatically turn
on and off during severe operating
conditions to protect the engine from
overheating. When the coolant temperature
decreases to the normal operating
temperature, the air conditioning turns on. If the coolant temperature gauge moves fully
into the red zone, or if the coolant
temperature warning or service engine soon
messages appear in your information display,
do the following:
1.
Stop your vehicle as soon as it is safe to
do so. Fully apply the parking brake, shift
into park (P) or neutral (N).
2. Leave the engine running until the coolant temperature gauge needle
returns to the normal position. If the
temperature does not drop after several
minutes, follow the remaining steps.
3. Switch the engine off and wait for it to cool. Check the coolant level.
4. If the coolant level is at or below the minimum mark, add prediluted coolant
immediately.
5. If the coolant level is normal, restart the engine and continue.
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CHANGING THE ENGINE AIR
FILTER
WARNING: To reduce the risk of
vehicle damage and personal burn injuries,
do not start your engine with the air
cleaner removed and do not remove it
while the engine is running.
When changing the air filter element, use
only the air filter element listed.
See
Capacities and Specifications (page 400).
For turbocharged equipped vehicles: When
servicing the air cleaner, it is important that
no foreign material enter the air induction
system. The engine and turbocharger are
susceptible to damage from even small
particles.
Change the air filter element at the proper
interval. See Scheduled Maintenance (page
459
). Note:
Failure to use the correct air filter
element may result in severe engine
damage. The customer warranty may be
void for any damage to the engine if the
correct air filter element is not used. 1. Release the clamps that secure the air
filter housing cover.
2. Carefully lift the air filter housing cover.
3. Remove the air filter element from the air
filter housing.
4. Wipe any dirt or debris from the air filter housing and cover to make sure no dirt
gets in the engine and to make sure you
have a good seal. 5.
Install a new air filter element. Be careful
not to crimp the filter element edges
between the air filter housing and cover.
This could cause filter damage and allow
unfiltered air to enter the engine if not
properly seated.
6. Install the air filter housing cover.
7. Engage the clamps to secure the air filter
housing cover to the air filter housing.
CHANGING THE FUEL FILTER
Your vehicle has a lifetime fuel filter that
integrates with the fuel tank. It does not need
regular maintenance or replacement.
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DRIVE BELT ROUTING OVERVIEW
- 2.0L
A. The long drive belt is on the first pulley
groove closest to the engine.
B. The short drive belt is on the second pulley groove farthest from the engine. DRIVE BELT ROUTING OVERVIEW
- 2.7L CHANGING THE 12V BATTERY
WARNING: Batteries normally
produce explosive gases which can cause
personal injury. Therefore, do not allow
flames, sparks or lighted substances to
come near the battery. When working near
the battery, always shield your face and
protect your eyes. Always provide correct
ventilation. WARNING:
When lifting a
plastic-cased battery, excessive pressure
on the end walls could cause acid to flow
through the vent caps, resulting in personal
injury and damage to the vehicle or battery.
Lift the battery with a battery carrier or with
your hands on opposite corners.
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WARNING: Keep batteries out of
reach of children. Batteries contain sulfuric
acid. Avoid contact with skin, eyes or
clothing. Shield your eyes when working
near the battery to protect against possible
splashing of acid solution. In case of acid
contact with skin or eyes, flush immediately
with water for a minimum of 15 minutes and
get prompt medical attention. If acid is
swallowed, call a physician immediately. WARNING:
Battery posts, terminals
and related accessories contain lead and
lead compounds, chemicals known to the
State of California to cause cancer and
reproductive harm. Wash your hands after
handling
. WARNING:
This vehicle may have
more than one battery. Removing the
battery cables from only one battery does
not disconnect your vehicle electrical
system. Make sure you disconnect the
battery cables from all batteries when
disconnecting power. Failure to do so may
cause serious personal injury or property
damage.
The battery is in the engine compartment.
See
Under Hood Overview (page 334).
Your vehicle has a maintenance-free battery.
It does not require additional water during
service.
For longer, trouble-free operation, keep the
top of the battery clean and dry and the
battery cables tightly fastened to the battery
terminals. If any corrosion is present on the
battery or terminals, remove the cables from
the terminals and clean with a wire brush.
You can neutralize the acid with a solution
of baking soda and water. We recommend that you disconnect the
negative battery cable terminal from the
battery if you plan to store your vehicle for
an extended period.
Note:
If you only disconnect the negative
battery cable terminal, make sure it is
isolated or placed away from the battery
terminal to avoid unintended connection or
arcing.
To maintain correct operation of the battery
management system, if you add any
electrical devices to your vehicle, do not
connect the ground connection directly to
the negative battery terminal. A connection
at the negative battery terminal can cause
inaccurate measurements of the battery
condition and potential incorrect system
operation.
Note: If you add electrical accessories or
components to your vehicle this may
adversely affect battery performance,
durability and the performance of other
electrical systems on your vehicle.
If you replace the battery make sure it
matches the electrical requirements of your
vehicle.
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If you disconnect or replace the battery and
your vehicle has an automatic transmission,
it must relearn its adaptive strategy. Because
of this, the transmission may shift firmly when
first driven. This is normal operation while
the transmission fully updates its operation
to optimum shift feel.
Remove and Reinstall the Battery
To disconnect or remove the battery, do the
following:
1. Apply the parking brake and switch the
ignition off.
2. Switch all electrical equipment off, for example lights and radio.
3. Wait a minimum of two minutes before disconnecting the battery.
Note: The engine management system has
a power hold function and remains powered
for a period of time after you switch the
ignition off. This is to allow diagnostic and
adaptive tables to be stored. Disconnecting
the battery without waiting can cause
damage not covered by the vehicle
Warranty. 4. Disconnect the negative battery cable
terminal.
5. Disconnect the positive battery cable terminal.
6. Remove the battery securing clamp.
7. Remove the battery.
8. To install, reverse the removal procedure.
Note: Before reconnecting the battery, make
sure the ignition remains switched off.
Note: Make sure the battery cable terminals
are fully tightened.
Note: After cleaning or replacing the battery,
make sure you reinstall the battery cover or
shield.
If you disconnect or replace the vehicle
battery, you must reset the following
features:
• Window bounce-back. See Windows
(page 130).
• Clock Settings.
• Pre-set radio stations.
• Steering Angle Sensor. Note:
To calibrate the steering angle sensor,
drive the vehicle above
30 mph (50 km/h)
for a minimum of 1.2 mi (2 km). Make sure to
drive straight ahead for a minimum of 30
seconds. Several vehicle functions are
disabled and a warning light could appear
until the sensor is calibrated.
Battery Management System
The battery management system monitors
battery conditions and takes actions to
extend battery life. If excessive battery drain
is detected, the system temporarily disables
some of the following features:
• Heated rear window.
• Heated seats.
• Climate control.
• Heated steering wheel.
• Audio unit.
• Navigation system.
A message may appear in the information
display to alert you that battery protection
actions are active.
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After battery replacement, or in some cases
after charging the battery with an external
charger, the battery management system
requires eight hours of vehicle sleep time to
relearn the battery state of charge. During
this time your vehicle must remain fully
locked with the ignition off.
Note:
If you add electrical accessories or
components to the vehicle, it may adversely
affect battery performance and durability.
This may also affect the performance of
other electrical systems in the vehicle.
Battery Disposal Make sure that you dispose of old
batteries in an environmentally
friendly way. Seek advice from
your local authority about recycling old
batteries. ADJUSTING THE HEADLAMPS
Vertical Aim Adjustment
The headlamps on your vehicle are properly
aimed at the assembly plant. If your vehicle
has been involved in a crash, have the aim
of the headlamp beam checked by an
authorized dealer.
Headlamp Aiming Target
8 ft (2.4 m).
A
Center height of lamp to ground.
B 25 ft (7.6 m).
C
Horizontal reference line.
D
Vertical Aim Adjustment Procedure
1. Park the vehicle directly in front of a wall
or screen on a level surface,
approximately 25 ft (7.6 m) away.
2. Measure the height of the headlamp bulb
center from the ground and mark an 8 ft
(2.4 m)
horizontal reference line on the
vertical wall or screen at this height.
Note: To see a clearer light pattern for
adjusting, you may want to block the light
from one headlamp while adjusting the
other.
3. Turn on the low beam headlamps to illuminate the wall or screen and open
the hood.
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