2021 FORD MUSTANG check engine light

•
Do not warm up your vehicle on cold
mornings.
• Reduce the use of air conditioning and
heat.
• Avoid using speed control in hilly
terrain.
• Do not rest your foot on the brake
pedal while driving.
• Avoid carrying unnecessary weight.
• Avoid adding particular accessories to
your vehicle (e.g. bug deflectors,
rollbars/light bars, running boards, ski
racks).
• Avoid driving with the wheels out of
alignment.
COLD WEATHER
PRECAUTIONS
The functional operation of some
components and systems can be affected
at temperatures below approximately
-13°F (-25°C).
BREAKING-IN
Your vehicle requires a break-in period. For
the first 1,000 mi (1,600 km), avoid driving
at high speeds, heavy braking, aggressive
shifting or using your vehicle to tow. During
this time, your vehicle may exhibit some
unusual driving characteristics.
Ground Clearance
Since ground clearance is reduced, use
caution when approaching curbs or curb
stops from the front and rear as vehicle
damage may occur. Additionally, when
crossing speed bumps or driveway curbs,
you should approach at a 45 degree angle
to reduce the risk of vehicle damage. DRIVING THROUGH WATER WARNING:
Do not drive through
flowing or deep water as you may lose
control of your vehicle.
Note: Driving through standing water can
cause vehicle damage.
Note: Engine damage can occur if water
enters the air filter.
Before driving through standing water,
check the depth. Never drive through water
that is higher than the bottom of the front
rocker area of your vehicle. When driving through standing water, drive
very slowly and do not stop your vehicle.
Your brake performance and traction may
be limited. After driving through water and
as soon as it is safe to do so:
•
Lightly press the brake pedal to dry the
brakes and to check that they work.
• Check that the horn works.
• Check that the exterior lights work.
• Turn the steering wheel to check that
the steering power assist works.
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing Driving Hints E266447

GENERAL INFORMATION
Have your vehicle serviced regularly to help
maintain its roadworthiness and resale
value. There is a large network of
authorized dealers that are there to help
you with their professional servicing
expertise. We believe that their specially
trained technicians are best qualified to
service your vehicle properly and expertly.
They are supported by a wide range of
highly specialized tools developed
specifically for servicing your vehicle.
If your vehicle requires professional service,
an authorized dealer can provide the
necessary parts and service. Check your
warranty information to find out which
parts and services are covered.
Use only recommended fuels, lubricants,
fluids and service parts conforming to
specifications. Motorcraft® parts are
designed and built to provide the best
performance in your vehicle.
Precautions
•
Do not work on a hot engine.
• Make sure that nothing gets caught in
moving parts.
• Do not work on a vehicle with the
engine running in an enclosed space,
unless you are sure you have enough
ventilation.
• Keep all open flames and other burning
material, such as cigarettes, away from
the battery and all fuel related parts.
Working with the Engine Off
1. Set the parking brake and shift the transmission to park (P), for automatic
transmission, or neutral (N), for manual
transmission.
2. Switch off the engine.
3. Block the wheels. Working with the Engine On 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.
1. Set the parking brake and shift the transmission to park (P), for automatic
transmission, or neutral (N), for manual
transmission.
2. Block the wheels.
OPENING AND CLOSING THE
HOOD
Opening the Hood 1.
Inside the vehicle, pull the hood release
handle located under the left-hand
side of the instrument panel.
2. Slightly lift the hood.
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing MaintenanceE142457

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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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing MaintenanceE107998

Start Option
Allows you to select the type of countdown
the information display shows before
starting an event.
Status Screen
Provides the status of your chosen
performance-related settings.
View/Clear Results
Allows you to view and clear the last and
saved results of the Acceleration Timer,
Brake Performance, and All Time Best
results.
Track Use Maintenance Intervals
Follow these maintenance intervals for
when you use your vehicle on a track or in
a high speed event. Vehicle Use and Example
Interval
Change the engine oil and filter
One track weekend or approximately 4
hours of track use
Change the rear axle fluid
Every 500 mi (800 km) 1
1 Change the fluid every 500 mi (800 km) or when a message appears in the information
display stating that the axle fluid is over temperature.
Timing Chain
If you use your vehicle extensively at a race
track or at high rpm, it is possible to exceed
the service life of the engine timing chain.
A wrench indicator light illuminates when
it is time for you to replace your chain.
Have your vehicle checked as soon as
possible.
Adjustable Camber Front Strut
Top Mounts
(If Equipped)
Your vehicle has adjustable strut mounts
which you can use to adjust the camber of
your vehicle before and after a track event
to the specifications listed in the Road
Course Alignment Recommendations table
previously shown.
Note: After your track day is complete,
return your car to the street alignment and
tire pressures. Aerodynamics
(If Equipped)
Adjustable Rear Wing
The rear wing generates aerodynamic
down-force at speeds greater than 50 mph
(80 km/h)
.
Regularly inspect the rear wing panel and
attachment points for damage or
looseness.
You can adjust the wing using the hole
pattern at the top of the stanchion.
Moving the wing up increases rear down
force and overall understeer. Moving the
wing down decreases the rear down force
and overall understeer.
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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

Body
•
Wash your vehicle thoroughly to
remove dirt, grease, oil, tar or mud from
exterior surfaces, rear-wheel housing
and the underside of front fenders.
• Periodically wash your vehicle if it is
stored in exposed locations.
• Touch-up exposed or primed metal to
prevent rust.
• Cover chrome and stainless steel parts
with a thick coat of auto wax to prevent
discoloration. Re-wax as necessary
when you wash your vehicle.
• Lubricate all hood, door and luggage
compartment hinges and latches with
a light grade oil.
• Cover interior trim to prevent fading.
• Keep all rubber parts free from oil and
solvents.
Engine
• Change the engine oil and filter prior to
storage because used engine oil
contains contaminates which may
cause engine damage.
• Start the engine every 15 days for a
minimum of 15 minutes. Run at fast
idle with the climate controls set to
defrost until the engine reaches normal
operating temperature.
• With your foot on the brake, shift
through all the gears while the engine
is running.
• We recommend that you change the
engine oil before you use your vehicle
again.
Fuel system
• Fill the fuel tank with high-quality fuel
until the first automatic shutoff of the
fuel pump nozzle. Cooling system
•
Protect against freezing temperatures.
• When removing your vehicle from
storage, check coolant fluid level.
Confirm that there are no cooling
system leaks and that fluid is at the
recommended level.
Disconnecting Your 12 Volt Battery
• Check and recharge as necessary. Keep
connections clean.
• If storing your vehicle for more than 30
days without recharging the battery,
we recommend that you disconnect
the battery cables to maintain battery
charge for quick starting.
Note: It is necessary to reset memory
features if you disconnect the battery
cables.
Brakes
• Make sure the brakes and parking brake
release fully.
Tires
• Maintain recommended air pressure.
Miscellaneous
• Make sure all linkages, cables, levers
and pins under your vehicle are covered
with grease to prevent rust.
• Move vehicles at least 25 ft (7.5 m)
every 15 days to lubricate working parts
and prevent corrosion.
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing Vehicle Care

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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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing Wheels and TiresE175978 E200523