2021 FORD MUSTANG warning

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
Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing MaintenanceE272660 E272661

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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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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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing Maintenance

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

6. Tighten the filler plug until you feel a
strong resistance.
Only use fluid that meets Ford
specifications. See Capacities and
Specifications (page 335).
AUTOMATIC TRANSMISSION
FLUID CHECK
If required, have an authorized dealer check
and change the transmission fluid at the
correct service interval. See
Scheduled
Maintenance (page 441).
The automatic transmission does not have
a transmission fluid dipstick.
Refer to your scheduled maintenance
information for scheduled intervals for fluid
checks and changes. Your transmission
does not consume fluid. However, if the
transmission slips, shifts slowly or if you
notice a sign of leaking fluid, contact an
authorized dealer.
Do not use supplemental transmission
fluid additives, treatments or cleaning
agents. The use of these materials may
affect transmission operation and result
in damage to internal transmission
components.
BRAKE FLUID CHECK WARNING:
Do not use any fluid
other than the recommended brake fluid
as this will reduce brake efficiency. Use
of incorrect fluid could result in the loss
of vehicle control, serious personal injury
or death. WARNING:
Only use brake fluid
from a sealed container. Contamination
with dirt, water, petroleum products or
other materials may result in brake
system damage or failure. Failure to
adhere to this warning could result in the
loss of vehicle control, serious personal
injury or death. WARNING:
Do not allow the fluid
to touch your skin or eyes. If this
happens, rinse the affected areas
immediately with plenty of water and
contact your physician. WARNING:
The brake system
could be affected if the brake fluid level
is below the MIN mark or above the MAX
mark on the brake fluid reservoir. 1. Park your vehicle on a level surface.
2. Look at the brake fluid reservoir to see
where the brake fluid level is relative
to the
MIN and the MAX marks on the
reservoir.
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Note:
If the brake fluid level is between the
MIN and the MAX marks on the reservoir, it
is acceptable.
Note: If the brake fluid level is below the
MIN
mark or above the MAX mark, have
your vehicle checked as soon as possible.
Note: To avoid fluid contamination, the
reservoir cap must remain in place and fully
tight, unless you are adding fluid.
Only use fluid that meets our
specifications. See
Capacities and
Specifications (page 335).
Brake Fluid Service Interval
Brake fluid absorbs water over time which
degrades the effectiveness of the brake
fluid. Change the brake fluid at the
specified intervals to prevent degraded
braking performance.
For detailed interval information, see
Scheduled Maintenance in your Owner's
Manual or your local maintenance guide.
CLUTCH FLUID CHECK -
MANUAL TRANSMISSION
The clutch and brake systems share the
same fluid reservoir. See
Brake Fluid
Check (page 269).
POWER STEERING FLUID
CHECK
Your vehicle is equipped with an electric
power steering (EPS) system. There is no
fluid reservoir to check or fill. 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. 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
.
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing Maintenance

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. WARNING:
For vehicles with
Auto-Start-Stop the battery requirement
is different. You must replace the battery
with one of exactly the same
specification.
The battery is in the engine compartment.
See
Under Hood Overview (page 258).
Your vehicle has a maintenance-free
battery. It does not require additional
water during service.
If the vehicle battery has a cover and vent
hose, make sure you correctly install it after
cleaning or replacing the battery.
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. If you replace the battery make sure it
matches the electrical requirements of
your vehicle.
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.
Battery Management System
(If
Equipped)
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 electrical systems to
protect the battery.
Systems included are:
• Heated rear window.
• Heated seats.
• Climate control.
• Heated steering wheel.
• Audio unit.
• Navigation system.
A message may appear in the information
displays to alert you that battery
protection actions are active. These
messages are only for notification that an
action is taking place, and not intended to
indicate an electrical problem or that the
battery requires replacement.
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 switched off.
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing Maintenance