What Size Fog Light Bulb for a 2013 Audi A4?

The 2013 Audi A4 typically uses H11 bulbs for the front fog lights on most trims equipped with factory halogen fog lamps, but exact fitment can vary by market, trim line (Premium, Premium Plus, Prestige, S line), and whether the car has xenon/LED headlamps or specific appearance packages, so owners should verify via the vehicle manual, VIN-based parts lookup, or a direct bulb inspection before purchase.

Understanding Fog Light Bulb Sizes on the 2013 Audi A4

For many owners, replacing fog light bulbs seems like a straightforward task—until they discover that bulb types can differ by configuration, region, and optional packages. The 2013 model year of the Audi A4 (B8.5 facelift) is no exception, and while H11 is the most common fog bulb size, it is not absolutely universal for every single configuration worldwide. That makes confirmation especially important if the vehicle has been modified or was ordered with non-standard lighting options.

Common Factory Fog Light Bulb Type: H11

On the majority of 2013 Audi A4 sedans and Avants sold with conventional halogen fog lamps, the factory-installed front fog light bulb type is H11. This applies primarily to the round fog lamps integrated into the lower front bumper, often framed by horizontal trim or mesh grilles in the facelifted B8.5 front fascia.

The list below outlines the most common scenarios in which an H11 bulb is used for a 2013 Audi A4’s fog lamps, based on typical North American and many European configurations.

• 2013 Audi A4 (B8.5) with standard halogen fog lights in the lower bumper
• Trim levels such as Premium and Premium Plus with non-LED fogs
• Cars equipped with xenon or HID low beams but separate halogen fog lights
• Most S line appearance packages that retain conventional fog lamp housings
• Vehicles without special regional lighting packages that substitute LEDs or delete fogs

In practice, this means that if your 2013 A4 has traditional, separate bumper-mounted fog lamps and no obvious LED fog modules, an H11 bulb is very likely the correct size, but verification is still recommended before ordering parts or upgrading to LED alternatives.

When the Bulb Type Might Differ

Although H11 is standard in many configurations, there are situations where the fog light setup on a 2013 Audi A4 may not follow the common pattern. Market-specific regulations, optional packages, and previous owner modifications can result in different fog lighting hardware or even the absence of fog lights entirely.

Different Trims and Regional Variations

The 2013 A4 was sold in multiple trims and across various markets worldwide, including North America, Europe, and other regions, each with its own option structures and lighting regulations. As a result, not every A4 will have the same fog light arrangement or even fog lights at all.

The following points summarize factors that may influence fog light bulb type or presence on a 2013 Audi A4.

• Region-specific equipment: Some European or other international versions may use different fog assemblies or include/exclude fog lamps to meet local regulations.
• LED and xenon headlight packages: Higher-end lighting packages may pair xenon or LED low beams with LED daytime running lights, and in some cases, fog lamps are deleted or integrated differently.
• S line or sport appearance packages: While many S line cars still use H11 bulbs in conventional housings, grille design and trim variations can change access and sometimes hardware, particularly if retrofits have been done.
• Previous-owner modifications: Aftermarket LED kits, projector fog housings, or custom bumpers can alter the socket type, adapter needs, or bulb interface.
• Fleet or special-order vehicles: Certain fleet or special configurations may differ from retail models in lighting content.

Because of these variables, relying solely on model year and badge can occasionally lead to ordering the wrong bulb, especially if the car’s lighting has been changed since it left the factory.

Models Without Traditional Fog Lights

Some 2013 Audi A4 configurations emphasize daytime running lights, xenon or LED headlamps, and cornering light functions rather than conventional low-mounted fog lamps. In such cases, there may be no separate fog bulb to replace.

The following are examples of setups where a typical H11 fog bulb might not be present.

• Front bumper designs that have blank grilles or trim panels where fog lights would normally exist
• Configurations where cornering or all-weather lighting is integrated into the headlamp housing, not the bumper
• Markets or trim levels that delete fog lights in favor of compliance with local regulations or cost savings
• Vehicles with fully LED front lighting modules that do not use conventional halogen fog bulbs

In these situations, what might be perceived as a “fog light” may actually be a cornering or auxiliary lamp integrated within the headlight cluster, which uses a different bulb size or LED module entirely.

How to Confirm the Correct Bulb Size for Your Car

Because there are occasional exceptions to the general H11 standard for the 2013 Audi A4, it is wise to confirm the correct bulb specification before purchasing replacements or upgrades. There are several practical ways to do this without guesswork.

Check the Owner’s Manual and Service Documentation

The most straightforward method is to consult the factory documentation provided with the car. Audi typically lists bulb specifications for the various exterior lights in the owner’s manual or in a dedicated lighting section.

The steps below describe how to use official documentation to identify the proper fog bulb size.

1. Open the owner’s manual and navigate to the “Lights” or “Bulbs” section, often in the maintenance chapter.
2. Locate the table or chart listing exterior lights by position (e.g., “Front fog light”).
3. Identify the bulb specification column, which should list a designation such as “H11” for halogen fog lamps.
4. If you have service records or a digital service history, check for any notes referencing lighting changes or retrofits.
5. If documentation is missing, many Audi digital manuals are accessible online by VIN through the manufacturer’s site or regional portals.

This documentation-based approach is particularly helpful for confirming whether your vehicle has stock equipment or has been altered by previous maintenance or upgrades.

Inspect the Fog Lamp Housing Directly

Physically inspecting the fog light assembly is another reliable method, especially if the car may have been modified or uses aftermarket components. Most fog lamps on the 2013 A4 can be accessed from beneath the bumper or via the inner wheel liner.

The following steps outline a typical visual inspection process to confirm bulb type directly from the housing or bulb.

1. Turn off the vehicle and ensure the lights are off; allow the lamps to cool if recently used.
2. Access the rear of the fog lamp housing via the wheel well or undertray, depending on the exact bumper setup.
3. Locate the bulb socket and gently twist it counterclockwise to remove it from the housing.
4. Examine the bulb base: many H11 bulbs are labeled “H11” and have a distinctive two-prong connector and L-shaped base.
5. Check the housing itself for molded markings or labels that may specify the intended bulb type.

Physically inspecting the bulb and housing can quickly clarify whether you’re dealing with a standard H11 setup or a different, potentially aftermarket arrangement.

Use a VIN-Based Parts Catalog or Dealer Lookup

Dealerships and many parts retailers can identify the correct bulb type using your vehicle identification number (VIN), ensuring you get an exact match for your specific build specification.

The following approaches are effective for VIN-based confirmation.

• Contact an Audi dealer’s parts department and provide your VIN for an official parts lookup.
• Use reputable online OEM parts catalogs that allow VIN decoding and model-specific diagrams.
• Compare the part number of the existing fog lamp bulb or assembly to the catalog listing, when possible.
• Verify that the catalog indicates a halogen H11 bulb for the fog position rather than an LED module or other format.

By matching your exact VIN to factory build data, this method reduces the chance of error that can arise from relying solely on model-year and trim assumptions.

Choosing Replacement or Upgrade Bulbs

Once you’ve confirmed that your 2013 Audi A4 uses H11 fog bulbs, you can decide whether to replace them with standard halogen units or upgrade to brighter, whiter, or LED-based alternatives. Each option carries trade-offs in brightness, lifespan, legality, and compatibility with the car’s electronics.

Halogen H11 Replacements

Standard halogen bulbs are the simplest and most straightforward option, maintaining factory performance and minimizing compatibility issues. They’re also inexpensive and widely available.

The list below summarizes characteristics and considerations for halogen H11 replacements.

• OEM-style halogen: Matches the original brightness, beam pattern, and color temperature specified by Audi.
• Enhanced-output halogen: “+30%”, “+60%” or similar marketing claims can provide a somewhat brighter or whiter beam, often with a shorter lifespan.
• Warm color temperature: Typically around 3200–3500K, which can be effective in fog, rain, and snow by reducing glare.
• Plug-and-play fit: No additional wiring or resistors needed when replacing H11 with H11.
• Legal compliance: Standard halogens usually conform to road regulations in most markets when using properly rated bulbs.

For drivers primarily seeking a straightforward, reliable maintenance replacement that preserves the car’s original character and regulatory compliance, OEM-style H11 halogens are a sound choice.

LED H11 Fog Light Upgrades

Many owners consider upgrading to LED H11 bulbs for a whiter, more modern look that better matches xenon or LED headlamps. However, compatibility considerations with reflectors, heat dissipation, and potential error messages in Audi’s bulb-monitoring system must be addressed.

The key points below outline common aspects of LED H11 fog light conversions in a 2013 A4.

• Whiter light output: LED fog bulbs often range from 5000K to 6500K, giving a crisp white or slightly blue-tinged color.
• Beam pattern considerations: Poorly designed LEDs can produce glare or uneven beams in housings designed for halogen filaments.
• CAN-bus compatibility: Some LED kits require built-in resistors or decoders to prevent dashboard bulb-out warnings or flicker.
• Heat management: Quality LED bulbs use heat sinks or fans; cramped fog housings must accommodate these components.
• Legal aspects: In some jurisdictions, replacing halogen bulbs with non-approved LED retrofits for road use may not be fully legal, especially without type approval.

For those who prioritize aesthetics and potentially improved visibility, a well-engineered, CAN-bus-compatible LED H11 kit from a reputable brand—installed with attention to beam alignment—can be effective, but it is important to check local regulations and product certifications.

Practical Tips for Replacing Fog Light Bulbs on a 2013 A4

Beyond knowing the correct bulb size, proper replacement technique and basic precautions help ensure safety and optimal performance. Access can be somewhat tight on the A4’s front bumper, but the process remains manageable for many owners with basic tools.

Preparation and Safety

Before starting work on your fog lights, take a few simple steps to ensure you can complete the job safely and efficiently, minimizing the risk of damage to the vehicle or the new bulbs.

The steps below outline good preparation practices for fog bulb replacement on a 2013 Audi A4.

1. Park the car on a flat, stable surface and set the parking brake.
2. Turn off the ignition and all lights; allow existing bulbs to cool completely.
3. Gather basic tools, such as a Torx or Phillips screwdriver, trim tools, and gloves.
4. Use clean gloves or a lint-free cloth when handling halogen bulbs to avoid skin oils on the glass.
5. If necessary, raise the front of the car slightly with a jack and use jack stands for secure support.

These preparations reduce the chance of burned fingers, cracked glass, or accidental damage to the bumper and inner fender liners during bulb access.

Accessing the Fog Lamp Housing

Depending on your exact bumper and trim configuration, you may reach the fog lamp from the front of the bumper, the wheel well, or underneath the car. Most 2013 A4s allow access via the wheel arch or by removing small covers in the bumper grilles.

The following methods summarize common approaches to gaining access to the fog lamp assembly.

• Wheel-well access: Turn the front wheels to one side, partially remove or flex back the inner fender liner, and reach the rear of the fog housing.
• Lower-bumper access: Remove a few fasteners in the lower undertray or splash shield to reach the fog lamp sockets from below.
• Front grille/trim removal: On some trims, fog lamp grille pieces can be gently pried out, exposing fasteners or the rear of the housing.
• Connector release: Disconnect the wiring plug from the fog bulb before twisting the bulb assembly free.
• Twist-and-pull removal: Rotate the bulb assembly (often counterclockwise) to unlock it from the fog housing.

Exact steps may vary slightly by bumper design and regional variant, so it can be helpful to consult a model-year–specific DIY guide or workshop manual for photographs illustrating access points.

Installing the New H11 Bulb

Once the old bulb is removed, carefully installing the new bulb and confirming proper operation is essential. Poor seating or misalignment may result in water ingress, vibration, or beam issues.

The steps below describe a typical H11 bulb installation process for the 2013 Audi A4’s fog lights.

1. Verify that the replacement bulb matches the original: H11 base, correct wattage and voltage rating.
2. Without touching the glass (for halogens), insert the new bulb into the fog housing, aligning the tabs with the slots.
3. Twist the bulb assembly clockwise until it locks firmly in place, ensuring a snug seal.
4. Reconnect the wiring harness connector, confirming it clicks into position and feels secure.
5. Before reassembling trim or liners, turn on the fog lights to check that both sides illuminate evenly and without warnings.

After confirming proper operation, reinstall any panels, grilles, or wheel-liner fasteners, making sure everything is secure and properly aligned to prevent rattles or moisture intrusion.

Key Takeaways and Final Verification

Most 2013 Audi A4 models equipped with factory fog lights use the H11 bulb size for the front fog lamps, especially when those lights are conventional halogen units housed in the lower front bumper. However, lighting packages, regional variants, and aftermarket modifications can result in differences, which makes personal verification valuable.

The points below summarize how to approach fog light bulb selection for this model year.

• Expect an H11 bulb type for standard halogen front fog lights on most 2013 A4s.
• Always confirm via the owner’s manual, a visual check of the bulb/housing, or a VIN-based parts lookup.
• Decide between OEM-style halogen replacements or carefully chosen LED upgrades, considering legal and compatibility factors.
• Follow basic safety and installation procedures to avoid damage and ensure consistent beam performance.
• If in doubt, consult an Audi dealer, specialist shop, or detailed service manual for configuration-specific guidance.

By combining the general knowledge that H11 is the standard fog bulb for most 2013 Audi A4 configurations with a quick check of your specific vehicle, you can confidently select and install the correct bulbs, preserving both safety and the car’s intended lighting performance.

Summary

For the 2013 Audi A4, the front fog light bulb is usually an H11 halogen, particularly on cars with conventional bumper-mounted fog lamps. Variations in trim, regional specification, and prior modifications mean that owners should still confirm the bulb type via the owner’s manual, a physical inspection of the existing bulb, or a VIN-based parts lookup. With the correct size verified, standard halogen replacements offer simple, compliant performance, while carefully selected LED H11 upgrades can modernize the appearance—provided they are compatible with the A4’s housing and electrical system and meet local regulations.