2014 Ford F-350 Super Duty Fuse Box Diagram & Amperage

Quick Answer

The 2014 Ford F-350 Super Duty typically has three main fuse box locations: under the hood (Power Distribution Box), behind the passenger kick panel (Smart Junction Box/Passenger Compartment Fuse Panel), and in the left-hand side of the engine compartment near the battery (Trailer Brake Controller Relay Box).

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Under-Hood Power Distribution Box

The Power Distribution Box is located in the engine compartment on the driver's side, near the battery. This box contains high-current fuses and relays for major electrical components.

Fuse #	Amp	Color	Circuit / Component Protected
F1	20A	Yellow	Powertrain Control Module (PCM)/Engine Control Module (ECM)
F2	10A	Red	Anti-lock Brake System (ABS) Module
F3	30A	Green	Fuel Pump Relay
F4	20A	Yellow	Starter Relay
F5	10A	Red	Ignition Coils
F6	30A	Green	Blower Motor
F7	10A	Red	A/C Clutch Relay
F8	15A	Blue	Headlights (Low Beam - Left)
F9	15A	Blue	Headlights (Low Beam - Right)
F10	20A	Yellow	Headlights (High Beam - Left)
F11	20A	Yellow	Headlights (High Beam - Right)
F12	10A	Red	Tail Lights / Park Lights
F13	15A	Blue	Brake Lights (Stop Lamps)
F14	20A	Yellow	Trailer Tow Battery Charge
F15	30A	Green	Trailer Brake Controller
F16	10A	Red	Oxygen Sensors
F17	10A	Red	Transmission Control Module (TCM)
F18	5A	Tan	Instrument Cluster
F19	20A	Yellow	Wipers (Front)
F20	20A	Yellow	Auxiliary Power Outlet (Console)

Relay Locations (Under-Hood Power Distribution Box):

• R1: Fuel Pump Relay
• R2: Starter Relay
• R3: PCM Relay
• R4: Blower Motor Relay
• R5: A/C Clutch Relay
• R6: High Beam Headlight Relay
• R7: Low Beam Headlight Relay

Note: Fuse and relay positions may vary slightly based on specific trim levels and options. Always refer to the fuse box diagram printed on the inside of the lid for your exact vehicle.

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Passenger Compartment Fuse Panel (Smart Junction Box)

The Smart Junction Box (SJB) is located behind the passenger kick panel, accessible by removing the cover. This panel contains fuses for various interior electrical systems and accessories.

Fuse #	Amp	Color	Circuit / Component Protected
F1	10A	Red	Radio/Infotainment System
F2	15A	Blue	Cigar Lighter / 12V Power Point (Front)
F3	15A	Blue	Auxiliary Power Point (Rear)
F4	10A	Red	Airbag Module (Restraint Control Module)
F5	5A	Tan	Instrument Cluster / Interior Lighting
F6	10A	Red	ABS Module (Interior Logic)
F7	20A	Yellow	Power Windows
F8	20A	Yellow	Power Door Locks
F9	10A	Red	Turn Signal/Hazard Flasher
F10	7.5A	Brown	Heated Mirrors
F11	15A	Blue	Seat Heaters
F12	5A	Tan	4x4 Shift-on-the-Fly Module
F13	10A	Red	Moonroof/Sunroof (if equipped)
F14	10A	Red	Trailer Brake Controller (Logic)
F15	5A	Tan	Diagnostic Link Connector (DLC)
F16	15A	Blue	Wiper Motor (Rear, if equipped)
F17	10A	Red	Ambient Lighting
F18	20A	Yellow	Power Seats
F19	15A	Blue	Horn
F20	10A	Red	Dome Light

Note: Always check the fuse legend on the cover of the Smart Junction Box for the most accurate information specific to your vehicle.

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Trailer Brake Controller Relay Box

For some 2014 Ford F-350 Super Duty models, particularly those equipped with the factory-integrated trailer brake controller, there might be a separate relay box specifically for trailer functions. This is typically located in the engine compartment on the left-hand side, near the battery or fender.

Fuse #	Amp	Color	Circuit / Component Protected
F1	30A	Green	Trailer Brake Feed (Main)
F2	20A	Yellow	Trailer Tow Left Turn/Brake Light
F3	20A	Yellow	Trailer Tow Right Turn/Brake Light
F4	20A	Yellow	Trailer Tow Park/Tail Lights
F5	30A	Green	Trailer Tow Backup Lights

Relay Locations (Trailer Brake Controller Relay Box):

• R1: Trailer Brake Relay
• R2: Trailer Backup Lamp Relay

(Verify exact location and configuration using your owner's manual or the label on the relay box cover.)

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How to Test a Fuse

Testing a fuse is a simple process that can help diagnose electrical issues. Here's how:

1. Locate the Fuse Box: Identify the correct fuse box for the circuit you're troubleshooting.
2. Identify the Suspect Fuse: Refer to the fuse diagram (either in this guide or on the fuse box lid/owner's manual) to find the fuse associated with the malfunctioning component.
3. Inspect Visually: Many fuses have a clear plastic body. Look for a broken wire or a dark, burnt appearance inside the fuse. If it's blown, the wire will be visibly separated.
4. Use a Multimeter (Recommended):
   • Set your multimeter to the continuity or ohm setting.
   • With the fuse removed from its slot, touch the multimeter probes to the metal test points on top of the fuse (or the metal blades themselves).
   • A good fuse will show continuity (a very low resistance reading, often with a beep). A blown fuse will show no continuity (infinite resistance).
5. Use a Test Light:
   • With the fuse in its slot and the circuit powered (e.g., ignition on for interior fuses), touch one probe of a 12V test light to a ground point on the vehicle and touch the other probe to each of the two small metal test points on top of the fuse.
   • If the test light illuminates on both sides, the fuse is good. If it only illuminates on one side or not at all, the fuse is blown.
6. Replace if Blown: If the fuse is blown, replace it with a new fuse of the exact same amperage rating and type. Using a fuse with a higher amperage can cause severe damage to your vehicle's electrical system or even a fire.

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Common Blown Fuses on this Vehicle

While any fuse can blow, some are more prone to failure due to the nature of the circuits they protect or common accessory usage. On a 2014 Ford F-350 Super Duty, common blown fuses often include:

• Cigar Lighter / 12V Power Outlets (Passenger Compartment F2, F3): These fuses commonly blow when accessories with high power draw are plugged in, or if there's a short circuit in the charger or device itself. Always check if a faulty accessory is the culprit.
• Trailer Brake Controller (Under-Hood F15, Passenger Compartment F14): Heavy trailer usage, shorts in trailer wiring, or issues with the trailer brake controller unit can cause these fuses to blow. Inspect trailer wiring carefully if you experience issues.
• Blower Motor (Under-Hood F6): A struggling blower motor due to debris, a worn motor, or even a faulty resistor can cause its fuse to blow. If your fan only works on certain speeds, suspect the resistor; if it doesn't work at all, check the fuse and the motor.
• Headlights (Under-Hood F8-F11): While less common with modern bulbs, a short in the wiring or an old, failing bulb can sometimes trip a headlight fuse. If only one headlight is out, it's more likely the bulb; if both are out, investigate the fuse or relay.
• Radio/Infotainment (Passenger Compartment F1): Issues with aftermarket radio installations, internal faults in the radio unit, or shorts in the antenna system can sometimes cause this fuse to blow. If your radio suddenly goes dead, this is a good place to start.

What to Check First: Before replacing a blown fuse, try to identify the cause. If you simply replace a fuse without addressing the underlying issue, the new fuse will likely blow again immediately. If an accessory caused it, remove the accessory. If you suspect a short, inspect the visible wiring for damage or chafing.

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