engine coolant FORD EXPLORER 2021 User Guide

AUTO-START-STOP (IF EQUIPPED)
The system helps reduce fuel consumption
by automatically stopping and restarting
the engine when your vehicle has stopped.
The engine restarts automatically when
you release the brake pedal.
In some situations, your vehicle may restart
automatically, for example:
• To maintain interior comfort.
• To recharge the battery.
Note: Power assist steering turns off when
the engine is off.
Note: If your vehicle is flex fuel capable,
Auto-Start-Stop will be inhibited for a short
time after a refuel event while the system
is verifying the fuel type being used. WARNING:
Apply the parking
brake, shift into park (P), switch the
ignition off and remove the key before
you leave your vehicle. Failure to follow
this instruction could result in personal
injury or death. WARNING:
Apply the parking
brake, shift into park (P), switch the
ignition off and remove the key before
you open the hood or have any service
or repair work completed. If you do not
switch the ignition off, the engine could
restart at any time. Failure to follow this
instruction could result in personal injury
or death. WARNING:
The system may
require the engine to automatically
restart when the auto-start-stop
indicator illuminates green or flashes
amber. Failure to follow this instruction
could result in personal injury. The Auto-Start-Stop system status is
available at a glance within the information
display.
See Information Displays (page
112).
Enabling Auto-Start-Stop
The system automatically enables every
time you start your vehicle if:
• You do not press the Auto-Start-Stop
button (not illuminated).
• Your vehicle exceeds an initial speed
of
3 mph (5 km/h) after you have
initially started your vehicle.
• You have stopped your vehicle.
• Your foot is on the brake pedal.
• The driver door is closed.
• The interior compartment has cooled
or warmed to an acceptable level.
• The front windshield defroster is off.
• You have not turned the steering wheel
rapidly or you do not have it at a sharp
angle.
• The vehicle is not on a steep road
grade.
• The battery is within optimal operating
conditions (battery state of charge and
temperature in range).
• The engine coolant is near operating
temperature.
• Elevation is below about
12,000 ft
(3,650 m).
• Ambient temperature is moderate.
• The trailer is not connected.
• If you select Normal, Eco, Snow/Wet
or Grass/Gravel/Snow modes.
• You are not in 4H or 4L.
• You have not selected Manual shift
mode.
• Hill descent control is not active.
• You have not selected Tow haul, Sport,
Sand or Mud/Rut modes.
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HYBRID VEHICLE FREQUENTLY ASKED QUESTIONS
Answer
Question
The high voltage battery is electrically isol-ated from the rest of the vehicle when the
key is off. When you switch the key on, high voltage contactors inside the battery are
closed to make the electricity available to the motor and generator and enable the
vehicle to drive. The clicks are the sound of these contactors as they close and open during start up and shut down.
What are the series of clicks from the cargo
area when I first turn the key in the ignition?
The vehicle's computer determines if an
engine start is required at key-on. Silent key starts the engine if it is necessary for cabin
heating, windshield defrost, or if the outside temperature is low.
Why does the engine sometimes start at
key-on?
There are several reasons the engine stayson for an extended amount of time when
you first start it. One common reason is to
make sure that the emissions components are warm enough to minimize tailpipe
emissions. As the climate gets cooler, this engine-on time is extended.
Why does it take a long time before the
engine shuts down?
In order to make sure that the climate
control system can begin heating the cabin
or defrosting the windshield as soon as you request it, the engine coolant temperature
has to be kept sufficiently hot. Keeping the
engine on is required to maintain the correct coolant temperature.
Why does my engine stay on when it is
extremely cold outside?
Your hybrid vehicle can use E15 fuel (15%ethanol, 85% gasoline), but you couldnotice slightly reduced fuel economy
because ethanol contains less energy per
gallon than gasoline. Your hybrid vehicle is not designed to use E85 (85% ethanol).
Can I put E15 or E85 in my vehicle, and how
will it affect my fuel economy?
The high voltage battery system is designedto last the life of the vehicle and requires no maintenance.
How long will my high voltage battery last?
Does it need maintenance?
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REDUCED ENGINE
PERFORMANCE
WARNING: If you continue to drive
your vehicle when the engine is
overheating, the engine could stop
without warning. Failure to follow this
instruction could result in the loss of
control of your vehicle.
If the engine coolant temperature gauge
needle moves to the upper limit position,
the engine is overheating. See Gauges
(page 106).
You must only drive your vehicle for a short
distance if the engine overheats. The
distance you can travel depends on
ambient temperature, vehicle load and
terrain. The engine continues to operate
with limited power for a short period of
time.
If the engine temperature continues to rise,
the fuel supply to the engine reduces. The
air conditioning switches off and the engine
cooling fan operates continually.
1. Gradually reduce your speed and stop your vehicle as soon as it is safe to do
so.
2. Immediately switch the engine off to prevent severe engine damage.
3. Wait for the engine to cool down.
4. Check the coolant level. See
Engine
Coolant Check (page 331).
5. Have your vehicle checked as soon as possible.
ECONOMICAL DRIVING
Fuel economy is affected by several things
such as how you drive, the conditions you
drive under and how you maintain your
vehicle. You may improve your fuel economy by
keeping these things in mind:
•
Accelerate and slow down in a smooth,
moderate fashion.
• Drive at steady speeds.
• Anticipate stops; slowing down may
eliminate the need to stop.
• Combine errands and minimize
stop-and-go driving.
• Close the windows for high-speed
driving.
• Drive at reasonable speeds (traveling
at
55 mph (88 km/h) uses 15% less
fuel than traveling at 65 mph
(105 km/h)).
• Keep the tires properly inflated and use
only the recommended size.
• Use the recommended engine oil.
• Perform all regularly scheduled
maintenance.
Avoid these actions; they reduce your fuel
economy:
• Sudden accelerations or hard
accelerations.
• Revving the engine before switching it
off.
• Idle for periods longer than one minute.
• Warm up your vehicle on cold
mornings.
• Use the air conditioner or front
defroster.
• Use the speed control in hilly terrain.
• Rest your foot on the brake pedal while
driving.
• Drive a heavily loaded vehicle or tow a
trailer.
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Protected Component
Fuse Rating
Fuse or Relay
Number
Body control module - battery power in
feed 1.
40A
1
Power outlet main console bin.
20A
2
Body control module - battery power in
feed 2.
40A
3
Fuel pump.
30A
4
Powertrain control module keep alive
power.
5A
5
Powertrain control module power.
20A
6
Canister vent solenoid.
20A
7
Evaporative leak control module.
Exhaust gas heat recovery (hybrid electric
vehicle).
Tank pressure control valve (hybrid electric
vehicle).
Refueling valve (plug-in hybrid electric
vehicle).
Vapor blocking valve.
Universal exhaust gas oxygen 11.
Universal exhaust gas oxygen 21.
Catalyst monitor sensor 12.
Catalyst monitor sensor 22.
Canister purge valve.
Cooling fan relay coil.
20A
8
Battery interrupt box.
Transmission oil pump.
Auxiliary coolant pump.
Fuel flap door (hybrid electric vehicle).
Engine coolant bypass valve.
Active grille shutters.
Ignition coils.
20A
9
Front blower motor relay.
40A
13
Transmission oil pump.
15A
14
A/C compressor variable clutch.
Auxiliary pumps (hybrid electric vehicle).
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Engine oil dipstick. See Engine Oil Dipstick (page 326).
C
Brake fluid reservoir. See
Brake Fluid Check (page 335).
D
Engine compartment fusebox. See
Changing a Fuse (page 320).
E
Engine coolant reservoir. See
Engine Coolant Check (page 331).
F
Air filter assembly. See
Changing the Engine Air Filter (page 328).
G
Windshield washer fluid reservoir. See
Washer Fluid Check (page 340).
H
UNDER HOOD OVERVIEW - 3.0L Battery.
See Changing the 12V Battery (page 336).
A
Engine oil filler cap.
See Engine Oil Check (page 326).
B
Engine oil dipstick.
See Engine Oil Dipstick (page 326).
C
Brake fluid reservoir.
See Brake Fluid Check (page 335).
D
Engine compartment fuse box.
See Fuses (page 312).
E
Engine coolant reservoir.
See Engine Coolant Check (page 331).
F
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Air filter assembly. See Changing the Engine Air Filter (page 329).
G
Washer fluid reservoir. See
Washer Fluid Check (page 340).
H
UNDER HOOD OVERVIEW - 3.3L Battery.
See Changing the 12V Battery (page 336).
A.
Engine oil filler cap.
See Engine Oil Check (page 326).
B.
Engine oil dipstick.
See Engine Oil Dipstick (page 326).
C.
Brake fluid reservoir.
See Brake Fluid Check (page 335).
D.
Engine compartment fuse box.
See Fuses (page 312).
E.
Engine coolant reservoir cap.
See Engine Coolant Check (page 331).
F.
Air filter assembly. See
Changing the Engine Air Filter (page 328).
G.
Inverter system controller coolant reservoir cap- HEV only.
H.
Washer fluid reservoir. See
Washer Fluid Check (page 340).
I.
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8. Install the air filter housing cover.
9. Engage the clips to secure the air filter
housing cover to the air filter housing.
10. Reconnect the boot to the air filter housing cover and torque to 3.69 lb.ft
(5 Nm).
ENGINE COOLANT CHECK 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. WARNING:
Do not put coolant in
the windshield washer reservoir. If
sprayed on the windshield, coolant could
make it difficult to see through the
windshield. WARNING:
To reduce the risk of
personal injury, make sure the engine is
cool before unscrewing the coolant
pressure relief cap. The cooling system
is under pressure. Steam and hot liquid
can come out forcefully when you loosen
the cap slightly. WARNING:
Do not add coolant
further than the MAX mark.
When the engine is cold, check the
concentration and level of the coolant at
the intervals listed in the scheduled
maintenance information. See Scheduled
Maintenance
(page 482).
Note: Make sure that the coolant level is
between the
MIN and the MAX marks on
the coolant reservoir. Note:
Coolant expands when it is hot. The
level may extend beyond the
MAX mark.
Maintain coolant concentration within
48% to 50%, which equates to a freeze
point between
-29°F (-34°C) and -35°F
(-37°C). Coolant concentration should be
checked using a refractometer. We do not
recommend the use of hydrometers or
coolant test strips for measuring coolant
concentration.
Adding Coolant WARNING:
Do not add engine
coolant when the engine is on or the
cooling system is hot. Failure to follow
this instruction could result in personal
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. WARNING:
Do not put coolant in
the windshield washer reservoir. If
sprayed on the windshield, coolant could
make it difficult to see through the
windshield.
Note: Do not use stop leak pellets, cooling
system sealants, or non-specified additives
as they can cause damage to the engine
cooling or heating systems. Resulting
component damage may not be covered by
the vehicle Warranty.
Note: Automotive fluids are not
interchangeable.
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It is very important to use prediluted
coolant approved to the correct
specification in order to avoid plugging the
small passageways in the engine cooling
system. See Capacities and
Specifications (page 391). Do not mix
different colors or types of coolant in your
vehicle. Mixing of engine coolants or using
an incorrect coolant may harm the engine
or cooling system components and may
not be covered by the vehicle Warranty.
Note: If prediluted coolant is not available,
use the approved concentrated coolant
diluting it to 50/50 with distilled water. See
Capacities and Specifications (page 391).
Using water that has not been deionised
may contribute to deposit formation,
corrosion and plugging of the small cooling
system passageways.
Note: Coolants marketed for all makes and
models may not be approved to our
specifications and may cause damage to
the cooling system. Resulting component
damage may not be covered by the vehicle
Warranty.
If the coolant level is at or below the
minimum mark, add prediluted coolant
immediately.
To top up the coolant level do the
following:
1. Unscrew the cap slowly. Any pressure escapes as you unscrew the cap.
2. Add prediluted coolant approved to the correct specification. See
Capacities and Specifications (page
391
).
3. Add enough prediluted coolant to reach the correct level.
4. Replace the coolant reservoir cap. Turn
the cap clockwise until it contacts the
hard stop. 5. Check the coolant level in the coolant
reservoir the next few times you drive
your vehicle. If necessary, add enough
prediluted engine coolant to bring the
coolant level to the correct level.
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.
In this instance, qualified personnel:
1. Must drain the cooling system.
2. Chemically clean the coolant system.
3. Refill with engine coolant 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:
• Alcohol.
• Methanol.
• Brine.
• Any coolant mixed with alcohol or
methanol antifreeze.
Alcohol and other liquids can cause engine
damage from overheating or freezing.
Do not add extra inhibitors or additives to
the coolant. These can be harmful and
compromise the corrosion protection of
the coolant.
Recycled Coolant
We do not recommend the use of recycled
coolant as an approved recycling process
is not yet available.
Note: Dispose of used coolant in the
appropriate manner.
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Follow your community's regulations and
standards for recycling and disposing of
automotive fluids.
Severe Climates
If you drive in extremely cold climates:
•
It may be necessary to increase the
coolant concentration above 50%.
• A coolant concentration of 60%
provides improved freeze point
protection.
• Coolant concentrations above 60%
decrease the overheat protection
characteristics of the coolant and may
cause engine damage.
If you drive in extremely hot climates:
• You can decrease the coolant
concentration to 40%.
• A coolant concentration of 40%
provides improved overheat protection.
• Coolant concentrations below 40%
decrease the overheat and corrosion
protection characteristics of the
coolant and may cause engine
damage.
Vehicles driven year-round in non-extreme
climates should use prediluted coolant for
optimum cooling system and engine
protection.
Coolant Change
At specific mileage intervals, as listed in
the scheduled maintenance information,
the coolant should be changed. Add
prediluted coolant approved to the correct
specification. See Capacities and
Specifications (page 391). 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
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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 may 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.
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:
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