The 2002–2004 Ford Super Duty trucks (F-250, F-350, F-450, and F-550) rely on a well-organized fuse system to protect their electrical circuits and components. Knowing the location and function of each fuse makes troubleshooting electrical issues much easier.
This guide provides detailed fuse box diagrams and descriptions to help you quickly identify and replace fuses when needed.
Table of Contents
2002 Ford F-250/F-350/F-450/F-550 Fuse Box Diagram
Ford F-250/F-350/F-450/F-550 built in the year 2002 feature only one fuse box layout commonly known as Passenger Compartment Fuse Panel / Power Distribution Box.
Passenger Compartment Fuse Panel / Power Distribution Box
| Fuse/Relay Location | Fuse Amp Rating | Description |
| 1 | 15A* | Adjustable pedals |
| 2 | — | Not used |
| 3 | — | Not used |
| 4 | 20A* | Power point – instrument panel |
| 5 | — | Not used |
| 6 | 20A* | Trailer tow turn/stop relay |
| 7 | 30A* | High beam headlamps/Flash to pass |
| 8 | — | Not used |
| 9 | — | Not used |
| 10 | 10A* | A/C clutch |
| 11 | 20A* | Radio (main) |
| 12 | 20A* | Cigar lighter / OBD II |
| 13 | 5A* | Power mirrors/switches |
| 14 | 15A* | Daytime running lamps (DRL) |
| 15 | — | Not used |
| 16 | — | Not used |
| 17 | 15A* | Exterior lamps |
| 18 | 20A* | Turn lamps/Brake on-off switch (high) |
| 19 | 10A* | Body security module/4×4 module |
| 20 | — | Not used |
| 21 | — | Not used |
| 22 | 20A* | Engine control |
| 23 | 20A* | Engine control (gasoline engine only) |
| 24 | 15A* | Not used (spare) |
| 25 | 10A* | 4-Wheel Anti-lock Brake System (4WABS) module |
| 26 | 10A* | Air bags |
| 27 | 15A* | Ignition switch Run feed |
| 28 | 10A* | EATC module/Front blower relay coil |
| 29 | 10A* | Customer access |
| 30 | 15A* | Highbeam headlamps |
| 31 | 15A* | Clutch interlock switch (manual transmissions only), Transmission range sensor (automatic transmissions only) then to starter relay coil (all transmissions) |
| 32 | 5A* | Radio (start) |
| 33 | 15A* | Front wiper |
| 34 | 10A* | Brake on-off switch |
| 35 | 10A* | Instrument cluster |
| 36 | 10A* | PCM Keep-Alive |
| 37 | 15A* | Horn |
| 38 | 20A* | Trailer tow park lamps and backup lamps |
| 39 | — | Not used |
| 40 | 20A* | Fuel pump |
| 41 | 10A* | Instrument cluster |
| 42 | 15A* | Delayed accessory |
| 43 | 10A* | Fog lamps |
| 44 | — | Not used |
| 45 | 10A* | Ignition switch Run/Start feed |
| 46 | 10A* | Left-hand lowbeam |
| 47 | 10A* | Right-hand lowbeam |
| 48 | — | Not used |
| 101 | 30A** | Trailer tow electric brake |
| 102 | 30A** | Door locks/Body security module |
| 103 | 50A** | Ignition switch |
| 104 | — | Not used |
| 105 | 30A** | Injector driver module (Diesel engine only) |
| 106 | 30A** | Front wiper main |
| 107 | 40A** | Front blower motor |
| 108 | — | Not used |
| 109 | 30A** | Heated seats |
| 110 | 50A** | Ignition switch |
| 111 | 30A** | 4WD/Shift on the fly |
| 112 | 30A** | Left-hand power seats |
| 113 | 30A** | Starter motor |
| 114 | 30A** | Right-hand power seats |
| 115 | 20A** | Trailer tow battery charge |
| 116 | 30A** | Ignition switch |
| 601 | 30A CB*** | Door window motors |
| 602 | 60A** | 4WABS module |
| 210 | — | Not used |
| 211 | — | Not used |
| 212 | — | Not used |
| 301 | — | Front blower motor relay |
| 302 | — | Powertrain (EEC) relay |
| 303 | — | Injector driver module relay (Diesel engine only) |
| 304 | — | Not used |
| 305 | — | Trailer tow battery charge relay |
| 306 | — | Delayed accessory relay |
| 307 | — | Starter relay |
| * Mini Fuses ** Maxi Fuses ***Circuit Breaker | ||
2003-2004 Ford F-250/F-350/F-450/F-550 Fuse Box Diagram
The 2003 and 2004 Ford F-250, F-350, F-450, and F-550 models have a single fuse box, commonly called the Passenger Compartment Fuse Panel or Power Distribution Box.
Passenger Compartment Fuse Panel / Power Distribution Box
| Fuse/Relay Location | Fuse Amp Rating | Description |
| 1 | 15A* | Adjustable pedals |
| 2 | — | Not used |
| 3 | — | Not used |
| 4 | 20A* | Power point – instrument panel |
| 5 | — | Not used |
| 6 | 20A* | Trailer tow turn/stop relay |
| 7 | 30A* | High beam headlamps/Flash to pass |
| 8 | 15A* | Backup lamps (Diesel engine only) |
| 9 | 20A* | Heated mirrors |
| 10 | 10A* | A/C clutch |
| 11 | 20A* | Radio (main) |
| 12 | 20A* | Cigar lighter / OBD II |
| 13 | 5A* | Power mirrors/switches |
| 14 | 15A* | Daytime running lamps (DRL) |
| 15 | — | Not used |
| 16 | — | Not used |
| 17 | 15A* | Exterior lamps |
| 18 | 20A* | Turn lamps/Brake on-off switch(high) |
| 19 | 10A* | Body security module/4×4 module |
| 20 | 10A* | Fuel Injection Control Module(FICM) relay (Diesel engine only) |
| 21 | — | Not used |
| 22 | 20A* | Engine control |
| 23 | 20A* | Engine control (gasoline engine only), Climate control (Diesel engine only) |
| 24 | 2A* | Brake pressure switch/Speed control |
| 25 | 10A* | 4-Wheel Anti-lock Brake System(4WABS) module, Variable Fan Control (VFC) (Diesel engine only) |
| 26 | 10A* | Air bags |
| 27 | 15A* | Ignition switch Run feed |
| 28 | 10A* | EATC module/Front blower relay coil |
| 29 | 10A* | Customer access |
| 30 | 15A* | Highbeam headlamps |
| 31 | 15A* | Clutch interlock switch (manual transmissions only), Transmission range sensor (automatic transmissions only) then to starter relay coil (all transmissions), 4×4 |
| 32 | 5A* | Radio (start) |
| 33 | 15A* | Front wiper |
| 34 | 10A* | Brake on-off switch |
| 35 | 10A* | Instrument cluster |
| 36 | 10A* | PCM Memory |
| 37 | 15A* | Horn |
| 38 | 20A* | Trailer tow park lamps |
| 39 | 15A* | Trailer tow back-up lamps |
| 40 | 20A* | Fuel pump |
| 41 | 10A* | Instrument cluster |
| 42 | 15A* | Delayed accessory |
| 43 | 10A* | Fog lamps |
| 44 | — | Not used |
| 45 | 10A* | Ignition switch Run/Start feed |
| 46 | 10A* | Left-hand lowbeam |
| 47 | 10A* | Right-hand lowbeam |
| 48 | — | Not used |
| 101 | 30A** | Trailer tow electric brake |
| 102 | 30A** | Door locks/Body security module |
| 103 | 50A** | Ignition switch (gasoline engine only), FICM power (Diesel engine only) |
| 104 | 40A** | Heated backlight |
| 105 | 30A** | Fuel heater (Diesel engine only) |
| 106 | 30A** | Front wiper main |
| 107 | 40A** | Front blower motor |
| 108 | — | Not used |
| 109 | 30A** | Heated seats |
| 110 | 50A** | Ignition switch |
| 111 | 30A** | 4WD/Shift on the fly |
| 112 | 30A** | Left-hand power seats |
| 113 | 30A** | Starter motor |
| 114 | 30A** | Right-hand power seats |
| 115 | 20A** | Trailer tow battery charge |
| 116 | 30A** | Ignition switch |
| 601 | 30A CB*** | Window motors, Moonroof |
| 602 | 60A** | 4WABS module |
| 210 | — | Not used |
| 211 | — | Backup lamps relay (Diesel engine only) |
| 212 | — | Not used |
| 301 | — | Front blower motor relay |
| 302 | — | Powertrain Control Module (PCM) relay |
| 303 | — | Fuel heater relay (Diesel engine only) |
| 304 | — | Heated backlight relay |
| 305 | — | Trailer tow battery charge relay |
| 306 | — | Delayed accessory relay |
| 307 | — | Starter relay |
| * Mini Fuses ** Maxi Fuses ***Circuit Breaker | ||
Tip: Some high-amperage fuses may look slightly different depending on the model year and trim. Always verify the fuse type before replacing.
Fuse Replacement Tips / Safety Precautions
- Always disconnect the negative battery terminal before removing fuses.
- Never replace a blown fuse with a higher amp rating — this can damage wiring or cause a fire.
- Use a fuse puller or needle-nose pliers for safety.
- Label replaced fuses for future reference.
Frequently Asked Questions (FAQs)
Why does the cigarette lighter (power socket) fuse keep blowing?
This usually happens when the circuit is overloaded, the wiring has a short, or the wrong fuse is used. High-power devices, damaged wires, or faulty adapters can all cause the fuse to blow. Using a lower-amperage fuse than Ford recommends may also lead to failures.
Why does the radio fuse keep blowing?
Radio fuse issues are often caused by shorted or damaged wires, added accessories, a faulty radio, or voltage spikes. Using the wrong fuse can also make it blow more easily.
Why does the fog light fuse keep blowing?
Fog light fuses typically fail due to damaged wiring, a bad bulb, a defective switch, or added/modified lights that overload the circuit.
Why does the tail light fuse keep blowing?
Tail light fuse problems are usually linked to shorted or damaged wires, faulty or incompatible bulbs, a bad switch, or an incorrectly rated fuse.
Why does the horn relay fail?
Horn relays fail mostly because of wiring shorts, wear and tear on the relay, or voltage spikes in the electrical system.
