2021 FORD F-150 fuse box

UNDER HOOD OVERVIEW - 3.5L, HYBRID ELECTRIC VEHICLE
(HEV)
Engine compartment fuse box. See Fuses (page 493).
A.
Battery.
See Changing the 12V Battery (page 519).
B.
Engine oil dipstick.
See Engine Oil Dipstick Overview (page 510).
C.
Engine oil filler cap.
See Adding Engine Oil (page 510).
D.
Brake fluid reservoir. See
Checking the Brake Fluid (page 309).
E.
Air filter.
See Changing the Engine Air Filter (page 517).
F.
Secondary coolant reservoir. See
Checking the Coolant (page 511).
G.
Engine coolant reservoir. See
Checking the Coolant (page 511).
H.
Windshield washer fluid reservoir.
I.
508
F-150 (TFD) Canada/United States of America, enUSA, Edition date: 202104, Second-Printing MaintenanceE333718

UNDER HOOD OVERVIEW - 5.0L
Engine compartment fuse box. See Under Hood Fuse Box (page 493).
A.
Engine oil filler cap.
See Engine Oil Dipstick Overview (page 510).
B.
Engine oil dipstick.
See Engine Oil Dipstick Overview (page 510).
C.
Brake fluid reservoir.
See Checking the Brake Fluid (page 309).
D.
Air filter assembly.
See Changing the Engine Air Filter (page 517).
E.
Engine coolant reservoir.
See Checking the Coolant (page 511).
F.
Windshield washer fluid reservoir.
G.
Battery.
See Changing the 12V Battery (page 519).
H.
509
F-150 (TFD) Canada/United States of America, enUSA, Edition date: 202104, Second-Printing MaintenanceE346494

WHAT ARE THE AUXILIARY
SWITCHES
The auxiliary switchboard on the overhead
console makes aftermarket customization
easier with six prewired switches
connected to the power distribution box.
Each circuit is individually fused for
connection of electrical accessories.
LOCATING THE AUXILIARY
SWITCHES
The auxiliary switchboard on the overhead
console makes aftermarket customization
easier with six prewired switches
connected to the power distribution box.
The circuits are individually fused for
connection of electrical accessories.
The switches have labels for AUX 1 through
AUX 6. They only operate when the ignition
is in the on position, whether the engine is
running or not. We recommend that you
leave the engine running to maintain
battery charge when using the switches
for an extended time or when using higher
current draw accessories. When you turn
on a switch, the indicator light on the
switch illuminates and the circuit provides
power to the device wired to that switch.
Note:
AUX switch 1 operates the off-road
lamps when your vehicle comes with this
option. LOCATING THE AUXILIARY
SWITCH WIRING
There are three sets of blunt-cut and
sealed circuits. Two sets are under the
hood and behind the battery tray, and one
set is inside your vehicle at the passenger
footwell.
The powered set (A) is taped behind the
battery tray and has a red spot tape mark.
The second set (B) is also under the hood.
It is taped behind the battery tray and has
a white spot tape mark. This set routes to
the interior passenger footwell.
Remove the battery and battery tray to
access the underhood circuits.
659
F-150 (TFD) Canada/United States of America, enUSA, Edition date: 202104, Second-Printing Auxiliary Switches - Raptor/TremorE220728 E347548 E347399

The interior set is taped on a wire harness
by the passenger side footwell. This set is
the other end of the circuits taped behind
the battery tray, with a white spot tape
mark.
Remove the fuse panel access door in the
kick panel to access the wires. If you do not
see them, you may need to pull them
down.
See Fuses (page 493). See your authorized
dealer for service.
Circuits from the under hood fuse box (A)
are powered. All other circuits (B-E) are
not connected at either end.
Additional information on fuse and relay
locations is available. See Fuses (page
493). See your authorized dealer for service.
IDENTIFYING THE AUXILIARY SWITCH WIRING
The relays are coded as follows: Fuse
Wire Size
Passenger
Footwell
Wire Color
Under-
hoodPass
Through
Wire Color
Power
Distribu- tion Box
10A
1.0 mm²
AUX 1
Violet/Green
AUX 1
Violet/Green
AUX 1
15A
1.0 mm²
AUX 2
Green/Brown
AUX 2
Green/
Brown
AUX 2
15A
1.0 mm²
AUX 3
Green/Blue
AUX 3
Green/Blue
AUX 3
10A
1.0 mm²
AUX 4
Brown
AUX 4
Brown
AUX 4
5A
1.0 mm²
AUX 5
Blue/Orange
AUX 5
Blue/Orange
AUX 5
5A
1.0 mm²
AUX 6
Yellow/
Orange
AUX 6
Yellow/
Orange
AUX 6
660
F-150 (TFD) Canada/United States of America, enUSA, Edition date: 202104, Second-Printing Auxiliary Switches - Raptor/Tremor

Blind Spot Information System.............389
Blind Spot Information System –
Troubleshooting............................................ 392
Blind Spot Information System With Trailer Coverage.......................................................... 390
Blind Spot Information System Indicators.....................................................392
Blind Spot Information System Limitations..................................................389
Blind Spot Information System Precautions................................................389
Blind Spot Information System Requirements............................................389
Blind Spot Information System – Troubleshooting........................................392
Blind Spot Information System – Information Messages................................ 392
Blind Spot Information System With Trailer Coverage........................................390
Blind Spot Information System With Trailer
Coverage Limitations.................................. 390
Selecting a Trailer.............................................. 392
Setting a Trailer Length.................................... 391
What Is Blind Spot Information System with Trailer Coverage............................................ 390
BlueCruise Alerts
.........................................368
BlueCruise Automatic Cancellation...............................................368
BlueCruise......................................................365 BlueCruise – Troubleshooting......................369
BlueCruise Indicators
.................................368
BlueCruise Limitations..............................366
BlueCruise Precautions
.............................365
BlueCruise Requirements........................366
BlueCruise Settings.....................................367
BlueCruise – Troubleshooting................369 BlueCruise – Information Messages..........369
Bluetooth®....................................................648
Body Control Module Fuse Box.............499 Accessing the Body Control Module Fuse
Box..................................................................... 499
Identifying the Fuses in the Body Control Module Fuse Box.......................................... 499
Locating the Body Control Module Fuse Box..................................................................... 499
Bonnet Lock See: Opening and Closing the Hood..........503
Booster Seats
.................................................60 Brake Fluid Specification.........................309
Brake Over Accelerator.............................308
Brake Over Accelerator - Raptor...........308
Brake Precautions
.......................................308
Brakes..............................................................308 Anti-Lock Braking System............................. 308
Brakes – Troubleshooting............................... 310
Brakes – Troubleshooting.........................310 Brakes – Frequently Asked
Questions......................................................... 310
Brakes – Warning Lamps................................ 310
Breaking-In.....................................................476
C
Calculating Payload
.....................................415
Calculating the Load Limit........................415
Canceling the Set Speed...........................351
Canceling the Set Speed - Raptor........324
Capacities and Specifications................574
Catalytic Converter......................................279 Catalytic Converter –
Troubleshooting............................................ 279
Catalytic Converter Precautions............279
Catalytic Converter – Troubleshooting........................................279
C

atalytic Converter – Warning
Lamps................................................................ 279
Center Console Work Surface.................228 C

enter Console Work Surface –
Troubleshooting............................................ 230
Center Console Work Surface – Troubleshooting........................................230
Center Console Work Surface – Information Messages......................................................... 230
Center Display Limitations.......................637
Center Display Overview
...........................637
Center Display Precautions......................637
Changing a Flat Tire...................................566
Changing a Road Wheel...........................566
Changing the 12V Battery..........................519
Changing the Fuel Filter - Diesel............519
Changing the Fuel Filter - Gasoline.......519
Changing the Remote Control Battery - Police Responder.........................................91
Changing the Remote Control Battery - Vehicles With: Flip Key..............................94
770
F-150 (TFD) Canada/United States of America, enUSA, Edition date: 202104, Second-Printing Index

Four-Wheel Drive –
Troubleshooting........................................297
Four-Wheel Drive – Information Messages......................................................... 297
Four-Wheel Drive – Warning Lamps..........297
Front Axle Fluid Capacity and Specification - 4x4...................................616
Front Exterior...................................................43
Front Exterior - Police Responder............45
Front Exterior - Raptor.................................44
Front Parking Aid.........................................335 Front Parking Aid Audible Warnings...........336
Front Parking Aid Limitations........................ 335
Locating the Front Parking Aid Sensors............................................................. 336
What is the Front Parking Aid....................... 335
Front Passenger Sensing System............76 Front Passenger Sensing System
Indicators............................................................ 78
Front Passenger Sensing System Precautions........................................................ 78
How Does the Front Passenger Sensing System Work..................................................... 76
What Is the Front Passenger Sensing System................................................................. 76
Front Seat Precautions..............................195
Front Seats.....................................................195 Heated Seats....................................................... 202
Manual Seats....................................................... 196
Massage Seats.................................................... 201
Power Seats......................................................... 198
Ventilated Seats................................................. 203
Fuel and Refueling
......................................255
Fuel and Refueling –
Troubleshooting............................................ 267
Fuel Quality.......................................................... 256
Refueling................................................................ 261
Running Out of Fuel......................................... 260
Fuel and Refueling Precautions.............255
Fuel and Refueling – Troubleshooting........................................267
Fuel and Refueling – Information Messages..........................................................267
Fuel and Refueling – Warning Lamps................................................................ 267
Fuel Gauge
........................................................171
Fuel Gauge Limitations..................................... 172
Locating the Fuel Filler Door........................... 172What Is Distance to Empty..............................
172
What Is the Fuel Gauge..................................... 171
What Is the Low Fuel Reminder..................... 172
Fuel Quality
...................................................256
Selecting the Correct Fuel.............................. 256
Selecting the Correct Fuel for Cold Weather............................................................ 257
Switching Between E85 and Gasoline........................................................... 260
Fuel Tank Capacity - Diesel
....................604
Fuel Tank Capacity - Excluding: Hybrid Electric Vehicle (HEV)............................266
Fuel Tank Capacity - Gasoline, Excluding: Hybrid Electric Vehicle (HEV)
.............603
Fuel Tank Capacity - Gasoline, Hybrid Electric Vehicle (HEV)............................605
Fuel Tank Capacity - Hybrid Electric Vehicle (HEV)
.............................................267
Fuel Tank Capacity - Raptor...................606
Fuse Precautions
.........................................493
Fuses................................................................493
Body Control Module Fuse Box................... 499
Fuses – Troubleshooting................................ 502
Under Hood Fuse Box...................................... 493
Fuses – Troubleshooting..........................502 Fuses – Frequently Asked Questions........502
G
Garage Door Opener...................................210
Garage Door Opener Limitations...........210
Garage Door Opener Precautions..........210
Garage Door Opener Radio Frequencies..................................................213
General Maintenance Information.......664
Glare Free Lighting
.......................................155
Glare Free Lighting Indicators........................ 156
Glare Free Lighting Limitations..................... 156
Glare Free Lighting Precautions....................155
Glare Free Lighting Requirements................155
How Does Glare Free Lighting Work............155
Overriding Glare Free Lighting....................... 156
Switching Glare Free Lighting On and Off....................................................................... 156
Glare Free Lighting – Troubleshooting.........................................157
Glare Free Lighting – Information Messages........................................................... 157
776
F-150 (TFD) Canada/United States of America, enUSA, Edition date: 202104, Second-Printing Index

Trail One Pedal Drive Indicators...................326
Trail One Pedal Drive Limitations................325
Trail One Pedal Drive Precautions...............325
What Is Trail One Pedal Drive........................325
Trail One Pedal Drive – Troubleshooting........................................326
Trail One Pedal Drive – Information Messages......................................................... 326
Trail Turn Assist Indicators.......................328
Trail Turn Assist Limitations....................328
Trail Turn Assist Precautions...................328
Trail Turn Assist
............................................328
Trail Turn Assist – Troubleshooting............329
Trail Turn Assist – Troubleshooting........................................329
T

rail Turn Assist – Frequently Asked
Questions........................................................ 329
Trail Turn Assist – Information Messages......................................................... 329
Transfer Case Fluid Capacity and Specification - 4x4...................................614
Transfer Case Fluid Capacity and Specification - Raptor.............................615
Transmission Fluid Temperature Gauge..............................................................172
Transporting the Vehicle..........................489
Trip Computer - Vehicles With: 4.2 Inch Screen...........................................................180
Accessing the Trip Computer........................180
Resetting the Trip Computer......................... 180
Trip Computer - Vehicles With: 8 Inch Screen/12.3 Inch Screen.........................180
Accessing the Trip Computer........................180
Resetting the Trip Computer......................... 180
Turbo Boost Gauge.......................................172
Type Approvals............................................686
U
Under Hood Fus

e Box
................................493
Accessing the Under Hood Fuse Box.........493
Identifying the Fuses in the Under Hood
Fuse Box.......................................................... 494
Locating the Under Hood Fuse Box...........493
Under Hood Overview - 2.7L EcoBoost™................................................504
Under Hood Overview - 3.0L Diesel............................................................505 Under Hood Overview - 3.3L..................506
Under Hood Overview - 3.5L, Hybrid
Electric Vehicle (HEV)............................508
Under Hood Overview - 3.5L Ecoboost™.................................................507
Under Hood Overview - 5.0L..................509
Under Seat Storage
....................................233
Locating the Under Seat Storage
Compartment................................................ 233
Unique Features..............................................33
Updating the Vehicle Systems Wirelessly....................................................656
USB Ports
........................................................214
Using a Slide-In Camper............................413
Using Auto Hold............................................318
Using Bead-Lock Wheels - Raptor.......553
Using Keyless Entry.....................................108
Using MyKey With Remote Start Systems........................................................100
Using On-Board Scale...............................444
Using Progressive Range Selection......................................................286
Using Smart Hitch.......................................442
Using Snow Chains......................................551
Using the Center Console Work Surface - Vehicles With: Column Shift..............228
Using the Center Console Work Surface - Vehicles With: Console Shift.............229
Using the Instrument Cluster Display Controls.........................................................178
Using the Integrated Trailer Brake Controller.....................................................434
Using the Keyless Entry Keypad................111
Using the Remote Control - Police Responder.....................................................89
Using the Remote Control
.........................90
Using the Trailer Backup Assistance Controller....................................................450
Using the Trailer Backup Assistance Views..............................................................451
Using This Publication..................................25
Using Trailer Hitching Assistance.........440
Using Trailer Reverse Guidance Views.............................................................463
790
F-150 (TFD) Canada/United States of America, enUSA, Edition date: 202104, Second-Printing Index