2021 FORD MUSTANG ECU

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

Note:
Prior to relearning the battery state
of charge, the battery management system
may temporarily disable some electrical
systems.
Electrical Accessory Installation
To make sure the battery management
system works correctly, do not connect an
electrical device ground connection
directly to the battery negative post. This
can cause inaccurate measurements of
the battery condition and potential
incorrect system operation.
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.
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.
If you disconnect or replace the vehicle
battery, you must reset the following
features:
• Window bounce-back. See Power
Windows (page 86).
• Clock Settings.
• Pre-set radio stations.
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 in an accident, have
the alignment of your headlamps checked
by an authorized dealer.
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Note:
The Gurney flap comes with longer
size bolts to install it onto the rear spoiler.
Do not use the longer size bolts without
the Gurney flap attached or damage to
the spoiler may occur.
Brake Burnishing
The brakes should be properly burnished
prior to heavy track use. Excessive brake
noise may occur after the track burnish or
track use. Perform this procedure in a safe
manner on dry pavement, and in
compliance with all local and state
ordinances and laws regarding motor
vehicle operation. How to Burnish the Brakes
Initial low temperature bedding:
•
If your brakes already have 200 mi
(322 km) or more of city driving, skip
this step and go directly to the high
temperature bedding cycle procedure.
Otherwise, perform at least 30 stops
from
50 mph (80 km/h) at 1/3 g
deceleration with 1 mi (1.2 km) spacing
between stops. A deceleration gauge
can be accessed through the
TrackApps menu in your information
display.
High temperature bedding cycle:
• Beginning with cool brakes, perform 15
consecutive stops back to back,
accelerating at 3/4 throttle to
80 mph
(128 km/h) and braking to 20 mph
(32 km/h) at 1.0 g deceleration. The
brakes may omit an odor or smoke
during this part of the procedure.
Cool down:
• Cool the brakes down by driving one or
two laps, 5 mi (8 km)
, at 60 mph
(96 km/h) with minimal to no brake
usage.
Recovery low temperature bedding:
• Perform at least 30 stops from 50 mph
(80 km/h)
at 1/3 g deceleration with
0.7 mi (1.2 km) spacing between stops.
A deceleration gauge can be accessed
through the TrackApps menu in your
information display.
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How to Burnish the Brakes
Initial low temperature bedding:
•
If your brakes already have 200 mi
(322 km) or more of city driving, skip
this step and go directly to the high
temperature bedding cycle procedure.
Otherwise, perform at least 30 stops
from
50 mph (80 km/h) at 1/3 g
deceleration with 1 mi (1.2 km) spacing
between stops. A deceleration gauge
can be accessed through the
TrackApps menu in your instrument
display.
High temperature bedding cycle:
• Beginning with cool brakes, perform 15
consecutive stops back to back,
accelerating at 3/4 throttle to
80 mph
(128 km/h) and braking to 20 mph
(32 km/h) at 1.0 g deceleration. The
brakes may omit an odor or smoke
during this part of the procedure.
Cool down:
• Cool the brakes down by driving one or
two laps, 5 mi (8 km)
, at 60 mph
(96 km/h) with minimal to no brake
usage.
Recovery low temperature bedding:
• Perform at least 30 stops from 50 mph
(80 km/h)
at 13 g deceleration with
0.7 mi (1.2 km) spacing between stops.
A deceleration gauge can be accessed
through the TrackApps menu in the
instrument cluster display.
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing Track Use

General Information
WARNING: Failure to follow these
guidelines could result in an increased
risk of loss of vehicle control, injury or
death.
Note: Do not use the kit if you have severely
damaged a tire. Only seal punctures within
the tire tread with the kit.
Do not attempt to repair punctures larger
than ¼ inch (6 millimeters) or damage to
the tire's sidewall. The tire may not
completely seal.
Loss of air pressure may adversely affect
tire performance. For this reason:
Note: Do not drive the vehicle above
50 mph (80 km/h)
.
Note: Do not drive further than
120 mi
(200 km). Drive only to the closest
authorized dealer or tire repair shop to have
your tire inspected.
• Drive carefully and avoid abrupt
steering maneuvers.
• Periodically monitor tire inflation
pressure in the affected tire; if the tire
is losing pressure, have the vehicle
towed.
• Read the information in the Tips for
Use of the Kit section to make sure safe
operation of the kit and your vehicle.
Tips for Use of the Kit
To ensure safe operation of the kit:
• Read all instructions and cautions fully.
• Before operating the kit, make sure
your vehicle is safely off the road and
away from moving traffic. Switch on
the hazard lights.
• Always set the parking brake to ensure
the vehicle does not move
unexpectedly. •
Do not remove any foreign objects,
such as nails or screws, from the tire.
• When using the kit, leave the engine
running (only if the vehicle is outdoors
or in a well-ventilated area) so the
compressor does not drain the
vehicle's battery.
• Do not allow the compressor to
operate continuously for more than 15
minutes. This will help prevent the
compressor from overheating.
• Never leave the kit unattended during
operation.
• Sealant compound contains latex.
Those with latex sensitivities should
use appropriate precautions to avoid
an allergic reaction.
• Keep the kit away from children.
• Only use the kit when the ambient
temperature is between -22°F (-30°C)
and 158°F (70°C).
• Only use the sealing compound before
the use-by date. The use-by date is on
a label on the sealant canister, which
you can see through the rectangular
viewing window on the bottom of the
compressor. Check the use-by date
regularly and replace the canister when
the sealant expires.
• Do not store the kit unsecured inside
the passenger compartment of the
vehicle as it may cause injury during a
sudden stop or crash. Always store the
kit in its original location.
• After sealant use, an authorized dealer
must replace the tire pressure
monitoring system sensor and valve
stem on the wheel.
• Operating the kit could cause an
electrical disturbance in radio, CD and
DVD player operation.
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing Wheels and Tires

* When inflation only is required
for a tire or other objects, the
selector must be in the Air
position.
What to do When a Tire Is
Punctured
You can repair a tire puncture within the
tire's tread area in two stages with the kit.
• In the first stage, inflate the tire with a
sealing compound and air. After you
inflate the tire, you will need to drive
the vehicle a short distance 4 mi
(6 km) to distribute the sealant in the
tire.
• In the second stage, check the tire
pressure and adjust, if necessary, to the
vehicle's specified tire inflation
pressure.
First Stage: Inflating the Tire with
Sealing Compound and Air WARNING:
Do not stand directly
over the kit while inflating the tire. If you
notice any unusual bulges or
deformations in the tire's sidewall during
inflation, stop and call roadside
assistance. WARNING:
If the tire does not
inflate to the recommended tire pressure
within 15 minutes, stop and call roadside
assistance. WARNING:
Do not run the engine
when operating the air compressor
unless the vehicle is outdoors or in a
well-ventilated area.
Preparation: Park the vehicle in a safe, level
and secure area, away from moving traffic.
Switch the hazard lights on. Apply the
parking brake and switch the engine off.
Inspect the flat tire for visible damage. Sealant compound contains latex. Use
appropriate precautions to avoid any
allergic reactions.
Do not remove any foreign object that has
pierced the tire. If a puncture is in the tire
sidewall, stop and call roadside assistance.
1. Remove the valve cap from the tire
valve.
2. Unwrap the dual purpose hose (black tube) from the back of the compressor
housing.
3. Fasten the hose to the tire valve by turning the connector clockwise.
Tighten the connection securely. 4. Plug the power cable into the 12-volt
power point in the vehicle.
5. Remove the warning sticker found on the casing/housing and place it on the
top of the instrument panel or the
center of the dash.
6. Start the vehicle and leave the engine running so the compressor does not
drain the vehicle ’s battery.
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•
Purchase chains or cables from a
manufacturer that clearly labels body
to tire dimension restrictions. The snow
chains or cables must be mounted in
pairs on the front or the rear tires only.
• Do not exceed 30 mph (50 km/h) if
recommended by the chain
manufacturer while using snow chains.
• Install cables securely, verifying that
the cables do not touch any wiring,
brake lines or fuel lines.
• Drive cautiously. If you hear the cables
rub or bang against the vehicle, stop
and retighten them. If this does not
work, remove the cables to prevent
vehicle damage.
• Remove the tire chains when they are
no longer needed. Do not use tire
chains on dry roads.
If you have any questions regarding snow
chains or cables, please contact your
authorized dealer.
TIRE PRESSURE MONITORING
SYSTEM WARNING:
The tire pressure
monitoring system is not a substitute for
manually checking tire pressures. You
should periodically check tire pressures
using a pressure gauge. Failure to
correctly maintain tire pressures could
increase the risk of tire failure, loss of
control, vehicle rollover and personal
injury.
Note: You should only use tire sealants in
roadside emergencies as they could cause
damage to the tire pressure monitoring
system sensor.
Note: If the tire pressure monitoring system
sensor becomes damaged, it will not
function. Each tire, including the spare (if
provided), should be checked
monthly when cold and inflated
to the inflation pressure recommended by
the vehicle manufacturer on the vehicle
placard or tire inflation pressure label. (If
your vehicle has tires of a different size
than the size indicated on the vehicle
placard or tire inflation pressure label, you
should determine the proper tire inflation
pressure for those tires).
As an added safety feature, your vehicle
has been equipped with a Tire Pressure
Monitoring System (TPMS) that
illuminates a low tire pressure telltale
when one or more of your tires is
significantly under-inflated. Accordingly,
when the low tire pressure telltale
illuminates, you should stop and check
your tires as soon as possible, and inflate
them to the proper pressure. Driving on a
significantly under-inflated tire causes the
tire to overheat and can lead to tire failure.
Under-inflation also reduces fuel efficiency
and tire tread life, and could affect the
vehicle ’s handling and stopping ability.
Please note that the TPMS is not a
substitute for proper tire maintenance, and
it is the driver ’s responsibility to maintain
correct tire pressure, even if under-inflation
has not reached the level to trigger
illumination of the TPMS low tire pressure
telltale.
Your vehicle has also been equipped with
a TPMS malfunction indicator to indicate
when the system is not operating properly.
The TPMS malfunction indicator is
combined with the low tire pressure
telltale. When the system detects a
malfunction, the telltale will flash for
approximately one minute and then remain
continuously illuminated. This sequence
will continue upon subsequent vehicle
start-ups as long as the malfunction exists.
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing Wheels and Tires