The 2020-2022 Ford F-450 Super Duty uses the updated P558-generation electrical layout. The fuse boxes share many assignments with other Super Duty trucks, but some fuse positions and spare slots changed between the 2020, 2021 and 2022 model years.
Trailer lighting, electric trailer brakes, four-wheel drive and auxiliary equipment deserve special attention on the F-450. A chassis-cab vehicle may also have additional fuse holders or circuit breakers fitted by the manufacturer of its recovery body, hydraulic equipment or other conversion.
Where are the fuse boxes in a 2020-2022 Ford F-450?
Engine compartment: the under-hood power distribution box protects high-current powertrain, ABS, steering, trailer, four-wheel-drive and accessory circuits. With the ignition switched off, open the hood, locate the power distribution box, release the cover clips and identify the numbered fuse positions.
Passenger compartment: the interior fuse panel is behind the access trim on the passenger side of the front footwell. Gently remove the cover to inspect fuses for the radio, SYNC, powered doors, windows, upfitter controls and the trailer brake system.
Engine compartment fuse box
| Position | Amperage [A] | Protected circuit / function |
|---|---|---|
| 1 | 20 | Power point 4 |
| 2 | 20 | Power point 3 |
| 3 | 10 | Spot lamp module |
| 4 | 10 | Four-wheel-drive vacuum solenoid |
| 5 | 40 | Active front steering system |
| 6 | 10 | Snowplow, if equipped |
| 7 | 30 | Trailer battery charging |
| 8 | 10 | ABS module |
| 9 | 10 | Electric power steering module |
| 10 | 30 | Trailer parking lamps |
| 11 | 20 | Horn |
| 12 | 30 | Torque Overlay system |
| 13 | 30 | Power sliding rear window |
| 14 | 40 | BCM battery feed 1 |
| 15 | 30 | Power passenger seat |
| 16 | 10 | PCM and TCM |
| 17 | 10 | BLIS blind spot monitoring system |
| 18 | 10 | Four-wheel-drive module |
| 19 | 5 | Adaptive cruise control |
| 20 | 15 | Heated mirrors |
| 21 | 40 | Heated rear window |
| 22 | 10 | OBD diagnostic module and Smart Data Link Connector |
| 23 | 15 | Transmission control module, TCM |
| 24 | 30 | Power driver seat |
| 25 | 25 | Voltage quality module |
| 26 | 30 | Trailer battery charging |
| 27 | 20 | Heated rear seats |
| 28 | 25 | Diesel: glow plugs. Gasoline: not used |
| 29 | 40 | Electric power steering motor |
| 30 | 10 / 10 / – | 2020: heated windshield wiper park area, 10 A. 2021: spare position, 10 A. 2022: not used |
| 31 | 20 | Power point 5 |
| 32 | 25 | Four-wheel-drive module |
| 33 | 10 | Alternator sense signal, circuit 2 |
| 34 | 50 | Gasoline: electric cooling fan. Diesel: auxiliary air heater |
| 35 | 20 | Power point 2 |
| 36 | 20 | Power point 1 |
| 37 | 60 | ABS pump |
| 38 | 60 | Power inverter |
| 39 | 25 | Four-wheel-drive module |
| 40 | 30 | Starter solenoid |
| 41 | 10 | Tailgate release solenoid |
| 42 | 40 | Blower motor |
| 43 | 10 | Trailer reversing lamps |
| 44 | 40 | Trailer lighting module |
| 45 | 30 | ABS valves |
| 46 | 30 | CNG module power supply, if equipped |
| 47 | 50 | Diesel: auxiliary air heater. Gasoline: not used |
| 48 | 50 | Diesel: auxiliary air heater. Gasoline: not used |
| 49 | – | Not used |
| 50 | 30 | Heated and ventilated seats |
| 51 | 20 | PCM module |
| 52 | 15 | Gasoline: CNG, if equipped. Diesel: fuel rail pressure relief valve control |
| 53 | 20 | Gasoline: EGR stepper motor and UEGO sensors. Diesel: EGR cooler bypass, DEF pump controller and oxygen sensors |
| 54 | 20 | A/C clutch relay feed and fan clutch |
| 55 | 5 | Rain sensor |
| 56 | 30 | Windshield wipers |
| 57 | 10 | Upfitter interface module |
| 58 | 10 | Alternator sense signal |
| 59 | 30 | Power running boards |
| 60 | 40 | BCM battery feed 2 |
| 61 | 10 | Power telescoping mirror motors |
| 62 | 40 | Trailer brake controller and auxiliary electric brake connection |
| 63 | 15 | Multicontour seats |
| 64 | 20 | Gasoline: ignition coil. Diesel: glow plug module, NOx module and DEF level and quality sensor |
| 65 | 30 | Fuel pump |
| 66 | 10 | Air-conditioning clutch solenoid |
| 67 | 40 | Auxiliary lighting module |
| 68 | 10 | PCM module |
| 69 | 60 | BCM power supply |
| 70 | 30 | Trailer stop lamps and turn signals |
For a related chassis-cab truck in the same model years, see the 2020-2022 Ford F-550 fuse box diagrams. Always check the precise model and fitted equipment instead of assuming the fuse boxes are identical.
Passenger compartment fuse panel
| Position | Amperage [A] | Protected circuit / function |
|---|---|---|
| 1 | – | Not used |
| 2 | 10 | Driver door switches and power sliding rear window switch |
| 3 | 7.5 | Seat memory switch, lumbar support motor and wireless charger |
| 4 | – / 20 | 2020: not used. 2021-2022: 20 A spare position |
| 5 | – | Not used |
| 6 | 10 | Power telescoping mirror switch and front power window switch |
| 7 | 10 | Brake on/off switch |
| 8 | 5 | Built-in modem |
| 9 | 5 | Integrated sensor module |
| 10 | – | Not used |
| 11 | – | Not used |
| 12 | 7.5 | OBD diagnostic module, Smart Data Link Connector and HVAC module |
| 13 | 7.5 | Steering column control module and instrument cluster |
| 14 | – / 15 | 2020: not used. 2021-2022: 15 A spare position |
| 15 | 15 | SYNC and display |
| 16 | – | Not used |
| 17 | 7.5 | Active steering module and parking aid module |
| 18 | 7.5 | Drive mode switch and SelectShift |
| 19 | 5 | Head-up display |
| 20 | 5 | Ignition switch and key interlock solenoid |
| 21 | 5 | Head-up display and temperature/humidity sensor |
| 22 | 5 | Upfitter switches |
| 23 | 30 | Driver front door module |
| 24 | 30 | Sunroof |
| 25 | – / 20 | 2020: not used. 2021-2022: 20 A spare position |
| 26 | 30 | Passenger front door module |
| 27 | – / 30 | 2020: not used. 2021-2022: 30 A spare position |
| 28 | 30 | Audio amplifier |
| 29 | 15 | Adjustable pedal switch |
| 30 | 5 | Brake on/off signal for trailer brake controller and customer-access circuits |
| 31 | 10 | Remote Keyless Entry |
| 32 | 20 | Radio |
| 33 | – | Not used |
| 34 | 30 | Run/start relay |
| 35 | – / 5 | 2020: not used. 2021-2022: 5 A spare position |
| 36 | 15 | Camera module, lane-keeping system, auto-dimming mirror and heated rear seats |
| 37 | 20 | Heated steering wheel |
| 38 | 30 | Power window circuit breaker |
What changed between 2020, 2021 and 2022?
Under-hood position 30 is a clear example. In 2020 it is a 10 A fuse for the heated windshield wiper park area; in 2021 it is a 10 A spare position; in 2022 Ford lists it as unused. From 2021, the interior panel also lists spare fuses at positions 4, 14, 25, 27 and 35. These assignments are preserved in the tables above.
Trailer circuits and body-builder equipment
If the trailer electrics fail, check the individual circuits rather than assuming one fuse supplies everything. Under the hood, positions 7 and 26 cover trailer battery charging, 10 the trailer parking lamps, 43 trailer reversing lamps, 44 the trailer lighting module, 62 the trailer brake controller, and 70 the trailer stop and turn signals.
Inside the cab, position 30 (5 A) provides the brake on/off signal for the trailer brake controller. Equipment installed by a body builder can use separate electrical protection beyond these original Ford fuse boxes.
The redesigned P708 generation introduced a different electrical arrangement. For that vehicle, consult the 2023 Ford F-450 Super Duty fuse box guide.
Ford F-450 2020-2022 FAQ
Are all three model years’ fuse boxes identical?
No. The layout is mostly shared, but several positions differ. These tables include all documented 2020, 2021 and 2022 variations from the Polish source.
Which fuse feeds the electric trailer brake controller?
The main controller supply is under the hood at position 62 (40 A), while the brake on/off signal has a separate 5 A fuse in interior position 30.
Does a body-builder conversion add more fuses?
It can. A flatbed, dump body, lift or hydraulic system may have separate fuses, relays and circuit breakers fitted by the conversion company.
Which diesel fuses are related to DEF and emissions controls?
On the 6.7-liter Power Stroke diesel, under-hood positions 53 and 64 relate to DEF and emissions components, and position 28 is associated with the glow plugs. A functioning fuse does not rule out faults in the wiring or modules.