FORD MUSTANG 2021 Owners Manual

UNDER HOOD OVERVIEW - 2.3L ECOBOOST™
Battery (out of view). See Changing the 12V Battery (page 270).
A
Engine oil dipstick. See
Engine Oil Dipstick (page 261).
B
Engine oil filler cap. See
Engine Oil Check (page 261).
C
Brake fluid reservoir. See
Brake Fluid Check (page 269).
D
Air filter assembly. See
Changing the Engine Air Filter (page 262).
E
Engine coolant reservoir. See
Engine Coolant Check (page 264).
F
Windshield washer fluid reservoir. See
Washer Fluid Check (page 274).
G
Power distribution box. See
Fuses (page 245).
H
Note: Your vehicle may not have an engine
cover as shown.
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing MaintenanceE174450

UNDER HOOD OVERVIEW - 5.0L
Battery (out of view). See Changing the 12V Battery (page 270).
A.
Engine oil filler cap. See
Engine Oil Check (page 261).
B.
Engine oil dipstick. See
Engine Oil Dipstick (page 261).
C.
Brake fluid reservoir. See
Brake Fluid Check (page 269).
D.
Air filter. See
Changing the Engine Air Filter (page 262).
E.
Engine coolant reservoir.
See Engine Coolant Check (page 264).
F.
Washer system fluid reservoir. See
Washer Fluid Check (page 274).
G.
Engine compartment fuse box. See
Fuses (page 245).
H.
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing MaintenanceE250052

UNDER HOOD OVERVIEW - 5.0L, MACH 1
Battery (out of view). See Changing the 12V Battery (page 270).
A
Engine oil filler cap.
See Engine Oil Check (page 261).
B
Engine oil dipstick.
See Engine Oil Dipstick (page 261).
C
Brake fluid reservoir.
See Brake Fluid Check (page 269).
D
Air filter assembly.
See Changing the Engine Air Filter (page 262).
E
Engine coolant reservoir.
See Engine Coolant Check (page 264).
F
Windshield washer reservoir.
See Washer Fluid Check (page 274).
G
Power distribution box.
See Changing a Fuse (page 254).
H
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing MaintenanceE296063

ENGINE OIL DIPSTICK
Minimum.
A
Nominal.
B
Maximum.
C
ENGINE OIL CHECK
1. Make sure that your vehicle is on level ground.
2. Check the oil before starting the engine
or switch the engine off and wait 10
minutes for the oil to drain into the oil
pan.
3. Remove the dipstick and wipe it with a clean, lint-free cloth.
4. Reinstall the dipstick and make sure it is fully seated. Remove it again to
check the oil level.
5. If the oil level is between the maximum
and minimum marks, the oil level is
acceptable. Do not add oil.
6. If the oil level is at the minimum mark, immediately add oil.
7. Reinstall the dipstick. Make sure it is fully seated.
Note: The oil consumption of new engines
reaches its normal level after approximately
3,000 mi (5,000 km). Adding Engine Oil WARNING: Do not remove the filler
cap when the engine is running. WARNING:
Do not add engine oil
when the engine is hot. Failure to follow
this instruction could result in personal
injury.
Do not use supplemental engine oil
additives. They could cause engine
damage that the vehicle warranty may not
cover.
1. Clean the area surrounding the engine oil filler cap before you remove it.
2. Remove the engine oil filler cap.
3. Add engine oil that meets our specifications. See
Capacities and
Specifications (page 343).
4. Reinstall the engine oil filler cap. Turn it clockwise until you feel a strong
resistance.
Note: Do not add oil further than the
maximum mark. Oil levels above the
maximum mark may cause engine damage.
Note: Soak up any spillage with an
absorbent cloth immediately.
OIL CHANGE INDICATOR
RESET
Use the information display controls on
the steering wheel to reset the oil change
indicator.
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From the main menu scroll to:
Action and description
Message
Press the right arrow button,
then from this menu scroll
to the following message.
Settings
Press OK
Advanced
Settings
Press the right arrow button,
then from this menu scroll
to the following message.
Vehicle
Press the right arrow button,
then from this menu scroll
to the following message.
Oil Life
Press and hold the OK
button until the instrument
cluster displays the
following message.
Hold OK to
Reset
Reset Successful
When the oil change indic-
ator resets the instrument
cluster displays 100%.
Remaining Life
{00}%
If the instrument cluster
displays one of the following
messages, repeat the
process.
Not Reset
Reset Cancelled CHANGING THE ENGINE AIR
FILTER - 5.0L, MACH 1 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.
See the scheduled maintenance
information for the appropriate intervals
for changing the air filter element.
When changing the air filter element, use
only the Motorcraft™ air filter element
listed. See the Motorcraft part numbers in
the Capacities and Specifications chapter. 262
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1. Remove the two sensor wire harness
retainers from the air box studs located
on the front side of the air box.
2. Remove the four studs that fasten the upper air box housing to the lower air
box housing.
3. Separate the upper air box housing from the lower air box housing.
4. Loosen the air filter clamp enough to allow the filter to slip off the housing
easily.
5. Remove the air filter from the air filter housing.
6. Wipe the newly-exposed air filter outlet
tube clamping area clean to remove
any dirt or debris.
7. Install a new air filter, taking care not to damage the air filter element. Align
the tab on the closed end of the filter
with the notch in the air filter housing.
8. Tighten the air filter clamp down.
Note: Do not overtighten the clamp or studs
when reinstalling.
9. Reinstall the upper air box piece to the
lower air box piece. Tighten the 4 studs
down.
10. Reinstall the two sensor wire harness
retainers to the mating air box studs.
CHANGING THE ENGINE AIR
FILTER - 2.3L ECOBOOST™/
5.0L 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. Note:
Failure to use the correct air filter
element may result in severe engine
damage. Your warranty may not cover
these damages.
Only use the specified replacement air
filter. See Motorcraft Parts (page 340).
For EcoBoost 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
intervals. Refer to Scheduled Maintenance
Information. 1. Release the two 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 that 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 it is not properly
seated.
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6. Replace the air filter housing cover.
7. Engage the clamps to secure the air
filter housing cover to the air filter
housing.
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 441).
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 335). 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 335).
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
335
).
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 335). 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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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing Maintenance