2017 Ford F-150 — Bulb Sizes (Headlight, Tail, Fog)

Quick reference

Notes on trim variation: 2017 F‑150 XL/XLT commonly use halogen reflector headlamps and incandescent tail lamps (bulb sizes above). Lariat/King Ranch/Platinum often have the optional factory LED headlamps and LED tail lamps where most exterior functions are sealed LED modules. Many trucks, including some with LED tails, still use a serviceable 921 backup bulb.

LED vs halogen upgrade considerations

• Headlights (H11/9005): Quality LED retrofit bulbs can reduce glare and preserve beam pattern in the factory reflector, but many budget LEDs scatter. Expect PWM-driven DRL on halogen trucks; use CANBUS/anti-flicker adapters if you see flicker or dash errors. Ensure the heat sink fits under the dust cap.
• Fog lights (9145/H10): Straightforward LED upgrade; choose a focused emitter to avoid stray glare. Some trims already have factory LED fogs (no bulb to change).
• Front/rear turns (3157A/3157): LED swaps will hyperflash without load resistors or an LED-capable flasher. Ford rear circuits are often CK/SRCK; choose CK‑compatible 3157 LEDs or re-pin appropriately.
• Brake/tail (3157): Use dual‑filament equivalent LEDs (switchback not needed in rear). Ensure they’re compliant and bright enough for daytime visibility.
• Reverse (921): Popular LED upgrade; no hyperflash concerns. Aim for 1,000–1,500 lumen class for meaningful improvement.
• Interior (194/578): CANBUS isn’t typically sensitive here, but low‑quality LEDs can glow faintly; choose non‑polar or CANBUS‑ready types if needed.

How to replace each bulb

• Low beam H11 / High beam 9005: Turn the wheel inward for access through the fender liner, or open the hood. Quarter‑turn the socket counterclockwise and withdraw. Don’t touch halogen glass; align tabs and quarter‑turn to lock.
• Factory LED headlamps: No serviceable bulbs; replace the lamp assembly if an LED fails.
• Fog light 9145/H10: Access from underneath or via fender liner; quarter‑turn to remove. On LED fogs, the whole lamp is serviced as an assembly.
• DRL: No separate bulb on halogen trucks; DRL is the low beam at reduced power, BCM controlled.
• Front turn/parking 3157A and front side marker 194: Access from rear of headlamp; twist sockets out. Seat new bulbs firmly; test hazards/parking before reassembly.
• Tail/brake/turn 3157 (incandescent tails): Lower tailgate, remove the two T‑27/T‑25 screws on the lamp edge, pull the housing straight back to release pins. Twist sockets; replace bulbs. If upgrading to LED, verify CK vs standard pinout.
• Reverse 921: With tail lamp removed, the bottom socket is the backup light; pull straight out and swap.
• Rear side marker 194: If equipped in your incandescent tail, serviced like other wedge bulbs; LED tails are non‑serviceable.
• License plate 194: Remove the two screws on each tag lamp lens; twist the socket and replace.
• Interior map 194: Gently pry the lens, release the bulb, and install the wedge LED/halogen. Observe polarity on LEDs.
• Interior dome 578 festoon: Pry the dome lamp lens, spring‑clip releases the festoon; install new 44mm (DE3022/578) and verify contact.

Common lighting issues for this generation

• Hyperflash after LED swaps: Add appropriate resistors or LED‑ready modules, and ensure CK‑compatible LEDs on rear circuits.
• PWM flicker/“bulb out” warnings: The BCM modulates voltage on exterior bulbs (especially DRL/low beam). Use CANBUS/anti‑flicker harnesses with LED headlight retrofits.
• Moisture in headlamps/fogs: 2015–2017 housings can develop condensation; inspect caps and vents. Severe moisture may require housing replacement.
• Melted/heat‑stressed 3157 sockets: Common on high‑mileage trucks; replace pigtails if contacts are loose or discolored.
• Dim reverse lights: Upgrade to high‑output 921 LEDs for better camera and mirror visibility.
• Tail lamp fitment damage: When removing the tail lamp, pull straight back to avoid breaking the alignment pins.

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