2021 FORD F-150 heating

Adding Coolant
WARNING: Keep your hands and
clothing clear of the cooling fan. 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 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 add coolant
further than the MAX mark. 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:
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.
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. 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 574). 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 could
void the vehicle Warranty.
Note: If prediluted coolant is not available,
use the approved concentrated coolant
diluting it to 50/50 with deionized or
distilled water. See
Capacities and
Specifications (page 574). Using water that
has not been deionized may contribute to
deposit formation, corrosion and plugging
of the small cooling system passageways.
To top up the coolant level do the
following:
1. Unscrew the cap slowly. Any pressure escapes as you unscrew the cap.
2. Add enough prediluted coolant to reach the correct level.
Note: We do not recommend the use of
recycled coolant.
3. Replace the coolant reservoir cap. Turn
the cap clockwise until it contacts the
hard stop.
4. Check the coolant level in the coolant reservoir the next few times you drive
your vehicle. If necessary, repeat step
2.
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.
Service your vehicle as soon as possible.
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F-150 (TFD) Canada/United States of America, enUSA, Edition date: 202104, Second-Printing Maintenance

Water alone, without engine coolant, can
cause engine damage from corrosion,
overheating or freezing.
Do not use the following as a coolant
substitute, as they can cause engine
damage from overheating or freezing:
•
Alcohol.
• Methanol.
• Brine.
• Any coolant mixed with alcohol or
methanol antifreeze.
Do not add extra inhibitors or additives to
the coolant. These can be harmful and
compromise the corrosion protection of
the coolant.
Severe Climates
If you drive in extremely cold climates, you
may need to increase the coolant
concentration above 50%.
Note: A coolant concentration of 60%
provides improved freeze point protection.
Coolant concentrations above 60%
decrease the overheat protection
characteristics of the coolant and could
cause engine damage.
If you drive in extremely hot climates, you
may need to decrease the coolant
concentration to 40%.
Note: A coolant concentration of 40%
provides improved overheat protection.
Coolant concentrations below 40%
decrease the overheat and corrosion
protection characteristics of the coolant and
could cause engine damage.
Coolant Change WARNING: Do not dispose of
coolant in the household refuse or the
public sewage system. Use an authorized
waste disposal facility. Change the coolant at specific mileage
intervals. Refer to the scheduled
maintenance information. See
Normal
Scheduled Maintenance (page 667).
Note: Dispose of used coolant in the
appropriate manner.
Follow your community's regulations and
standards for recycling and disposing of
automotive fluids.
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.
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F-150 (TFD) Canada/United States of America, enUSA, Edition date: 202104, Second-Printing Maintenance

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:
1. Stop your vehicle as soon as it is safe
to do so. Fully apply the parking brake,
shift into park (P) or neutral (N).
2. Leave the engine running until the coolant temperature gauge needle
returns to the normal position. If the
temperature does not drop after
several minutes, follow the remaining
steps.
3. Switch the engine off and wait for it to
cool. Check the coolant level.
4. If the coolant level is at or below the minimum mark, add prediluted coolant
immediately.
5. If the coolant level is normal, restart the engine and continue. ENGINE AIR FILTER
CHECKING THE ENGINE AIR
FILTER RESTRICTION GAUGE -
DIESEL
The air filter restriction gauge is in the
upper housing of the air filter assembly.
Check the air filter restriction gauge
whenever you open the hood to carry out
general engine maintenance. Change the
air filter element when the restriction
gauge reads near the change filter line and
the gauge is yellow. Allowing the restriction
gauge to reach maximum affects engine
performance and fuel economy.
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F-150 (TFD) Canada/United States of America, enUSA, Edition date: 202104, Second-Printing Maintenance E254173

It is important to rely upon your dealership
to properly diagnose and repair your
vehicle.
We strongly recommend only using our
genuine or our authorized re-manufactured
replacement parts engineered for your
vehicle.
Additives and Chemicals
We do not recommend using chemicals or
additives not approved by us as part of
your vehicle
’s normal maintenance. Please
consult your warranty information.
Oils, Fluids and Flushing
In many cases, fluid discoloration is a
normal operating characteristic and, by
itself, does not necessarily indicate a
concern or that the fluid needs to be
changed. Have discolored fluids that also
show signs of overheating or foreign
material contamination checked
immediately. Make sure to change the vehicle
’s oils and
fluids at the specified intervals or in
conjunction with a repair. Flushing is a
viable way to change fluid for many vehicle
sub-systems during scheduled
maintenance. It is critical that systems are
flushed only with new fluid that is the same
as that required to fill and operate the
system or using our approved flushing
chemical.
Owner Checks and Services
Make sure you perform the following basic
maintenance checks and inspections. Check Every Month
The air filter restriction gauge. 1
The engine oil level.
Function of all interior and the exterior lights.
The tires including the spare for wear and proper pressure. The windshield washer fluid level.
The fuel and water separator. Drain if necessary or if indicated by the information display. 1
The holes and slots in the tail pipe to make sure they are functional and clear of debris. 1
1 Diesel vehicles only.
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F-150 (TFD) Canada/United States of America, enUSA, Edition date: 202104, Second-Printing Scheduled Maintenance

Glasses Holder..............................................235
Locating the Glasses Holder.......................... 235
Glossary of Tire Terminology..................548
Glove Compartment...................................232
Locking the Glove Compartment................232
Opening the Glove Compartment...............232
H
Headlamp Adjusting See: Adjusting the Headlamps...................... 521
Headlamps......................................................147 Headlamp Indicators......................................... 147
Using the High Beam Headlamps................147
Headlamps – Troubleshooting...............148 Headlamps – Frequently Asked
Questions......................................................... 148
Heated Seats
................................................202
Heated Seat Precautions............................... 202
Switching the Heated Seats On and Off...................................................................... 202
Heating See: Climate Control - Vehicles With:
Automatic Temperature Control.............186
See: Climate Control - Vehicles With: Manual Temperature Control..................................... 191
High Voltage Battery..................................280
High Voltage Battery Precautions
.........280
High Voltage Battery Vehicle Precautions - Hybrid Electric Vehicle
(HEV)
............................................................484
Hill Descent Control...................................330
Hill Descent Control –
Troubleshooting............................................. 331
Hill Descent Control Indicator
................330
Hill Descent Control Precautions..........330
Hill Descent Control – Troubleshooting.........................................331
Hill Descent Control – Information Messages.......................................................... 331
Hill Start Assist...............................................317 Hill Start Assist – Troubleshooting..............317
Hill Start Assist Precautions.....................317
Hill Start Assist – Troubleshooting
........317
Hill Start Assist – Information
Messages........................................................... 317Hitches.............................................................424
Hooking Up a Trailer Using a
Weight-Distributing Hitch......................... 424
Hood Lock See: Opening and Closing the Hood..........503
Horn....................................................................141
How Does 911 Assist Work..........................87
How Does Active Park Assist Work..............................................................346
How Does Adaptive Cruise Control With Stop and Go Work....................................352
How Does a Hybrid Electric Vehicle Work..............................................................249
How Does Auto Hold Work.......................318
How Does Blind Spot Information System Work
..............................................389
How Does BlueCruise Work.....................365
How Does Cross Traffic Alert Work..............................................................393
How Does Drive Mode Control Work................................................................371
How Does Drive Mode Control Work - Raptor.............................................................371
How Does Driver Alert Work....................407
How Does Easy Entry and Exit Work.................................................................112
How Does Four-Wheel Drive Work
........291
How Does Four-Wheel Drive Work - Raptor
............................................................291
How Does Hill Descent Control Work..............................................................330
How Does Hill Start Assist Work
.............317
How Does On-Board Scale Work..........444
How Does Pre-Collision Assist Work
..............................................................396
How Does Reverse Braking Assist Work...............................................................314
How Does Smart Hitch Work..................442
How Does Speed Sign Recognition Work
..............................................................409
How Does Stability Control Work...........321
How Does the 360 Degree Camera Work...............................................................342
How Does the Diesel Particulate Filter Work..............................................................268
How Does the Electronic Locking Differential Work
.......................................301
777
F-150 (TFD) Canada/United States of America, enUSA, Edition date: 202104, Second-Printing Index