2014 Volvo VNL Bulb Size Guide: Headlight, Tail Light & More

Maintaining proper lighting on a commercial heavy-duty truck like the 2014 Volvo VNL is absolutely critical for nighttime visibility, DOT compliance, and overall safety. Whether you are dealing with a burnt-out low beam on a cross-country haul or looking to upgrade your interior cabin lighting, having the correct bulb sizes on hand will save you time and money.

Below is the complete bulb size guide for the 2014 Volvo VNL, covering both exterior and interior lights.

Quick Reference: 2014 Volvo VNL Bulb Sizes

Note: The Volvo VNL comes with a few different headlight and taillight configurations depending on the exact trim and spec. Always verify the bulb type currently installed before purchasing replacements, especially for rear tractor lights which are often sealed LED units.

LED vs. Halogen Upgrade Considerations

Many owner-operators and fleet managers choose to upgrade their 2014 Volvo VNL from factory halogen bulbs to aftermarket LEDs. LEDs provide a significantly brighter, whiter light output that reduces eye strain during long night drives. However, there are a few important things to keep in mind:

• CANBUS Systems and Flickering: The Volvo VNL utilizes a sophisticated electrical system. When upgrading to LEDs, the lower power draw can trigger "Bulb Out" warnings on the dash or cause the headlights to flicker. You will likely need CANBUS decoders or anti-flicker harnesses installed in-line with your new LED headlight bulbs.
• Projector Housings: The 2014 VNL typically features projector-style headlight housings. When choosing an H11 LED bulb for the low or high beams, ensure it is specifically designed to work well in projector housings. Some LEDs scatter light poorly in projectors, creating dangerous glare for oncoming drivers and reducing your actual down-road visibility.
• Space Constraints: Truck headlight assemblies can have tight clearances behind the dust cover. Make sure the cooling fan or heat sink on your LED bulb fits inside the housing without preventing the dust cover from sealing properly.

How to Replace Each Bulb

• Low and High Beam Headlights: Access to the headlight bulbs requires opening the hood. Behind the headlight assembly, you will find circular dust covers. Twist the cover counterclockwise to remove it, unplug the wiring harness, and twist the H11 bulb to pull it out. Be careful not to touch the glass of the new halogen bulb with bare skin.
• Front Turn Signals and DRLs: Located within the main headlight housing. Similar to the headlights, these are accessed from the rear. Twist the bulb socket counterclockwise, pull it out, and pull the old bulb straight out of the socket.
• Fog Lights: Reached from under the front bumper. You may need to remove a small splash shield depending on your specific bumper configuration. Unplug the harness and twist the bulb out.
• Rear Tractor Lights (Brake/Turn/Tail): Many fleets spec standard generic box lights or 4-inch round grommet lights. If it's a sealed LED unit, you must replace the entire assembly (unplug the 3-prong pigtail and pop the unit out of the rubber grommet). If it's a traditional box light, simply unscrew the plastic lens to access the 3157 bulbs inside.
• Interior Dome/Map Lights: Use a plastic trim tool to gently pry the plastic light covers off inside the cab. Pull the wedge or festoon bulbs straight out and snap the new ones in.

Common Lighting Issues for this Generation

The 2014 Volvo VNL generation is highly regarded, but it does experience a few specific lighting gremlins:

1. Wire Chafing: Heavy vibrations can cause wiring harnesses near the front bumper (especially around the fog lights and low beams) to chafe against the frame, leading to shorts and blown fuses.
2. Moisture in Headlight Assembly: The factory headlight seals can degrade over time. If you notice condensation building up inside the headlight lens, check the rear dust covers first. If the covers are intact, the main housing seal may be failing, requiring a complete assembly replacement.
3. Light Control Module (LCM) Faults: If you are experiencing erratic behavior—such as headlights turning off randomly or turn signals flashing rapidly despite all bulbs functioning—the issue might stem from the truck's Light Control Module.

Maintaining your commercial vehicle's lighting is a job you can largely do yourself, but electrical shorts and LCM issues require professional diagnostics. Find a trusted shop on Repairius.