Where to Find the Cabin Filter on an Audi A5

The cabin filter on most Audi A5 models is located behind the glovebox on the passenger side, while some earlier models may place an additional or alternative filter in the engine bay under the plastic cowl at the base of the windshield. Knowing the exact location depends on the model year and generation, but in all cases the filter is accessible without major disassembly and is designed to be a routine service item.

Understanding the Cabin Filter’s Role in the Audi A5

The cabin air filter in an Audi A5 cleans the air entering the interior through the heating, ventilation, and air conditioning (HVAC) system. It traps dust, pollen, soot, and other particles, and in many cases also absorbs odors through activated charcoal. Because it directly affects air quality, defogging performance, and in some cases blower noise, Audi places it where owners or technicians can replace it relatively easily.

Cabin Filter Location by Audi A5 Generation

The Audi A5 has been produced across several generations and facelifts. While the fundamental location of the cabin filter has stayed broadly consistent, there are some practical differences in access and layout between model years.

B8 Generation (Approx. 2008–2016: A5, S5, RS5)

On most B8 and B8.5 Audi A5 models, the primary cabin filter is located inside the cabin behind or beneath the glovebox on the passenger side. This applies to coupes, cabriolets, and many Sportback variants depending on market. The filter sits in a horizontal housing in the HVAC box.

Owners typically access this area from the passenger footwell. After removing the under-dash trim panel or a small access cover, the rectangular filter housing becomes visible. The filter slides out horizontally, usually toward the passenger seat.

B9 Generation (Approx. 2017–Present: A5, S5, RS5)

For the newer B9 and B9.5 Audi A5 models, the cabin filter also remains behind the glovebox on the passenger side in most markets. Audi refined the under-dash trim layout, but the basic idea is the same: the filter is in the HVAC housing, accessed from below or behind the glovebox area.

Some B9 models are equipped with enhanced particulate or “fine dust” filters, and in certain markets there can be a two-part filter set. The main access point, however, still sits in the passenger-side footwell area, just behind the glovebox, covered by a plastic panel and a filter housing cover.

Engine Bay / Cowl Area on Certain Early Models

On a few early European-market A5s and related Audi platforms sharing components, you may find an additional pollen filter or a different configuration that involves the plastic cowl panel at the base of the windshield. In those cases, part of the HVAC intake is under the hood, beneath a long plastic trim piece at the bottom of the windshield, usually on the passenger side.

Even in those variants, the filter is mounted in a dedicated slot or frame and is reachable after removing clips or screws holding the cowl trim. However, for the overwhelming majority of Audi A5 owners, particularly in North America and in later years, the cabin filter will be accessed from inside the vehicle rather than from the engine bay.

How to Access the Cabin Filter Inside the Audi A5

The precise trim layout and fastener style can vary slightly by model year and whether the car is left-hand or right-hand drive, but the overall access process is similar across A5 generations. The following breakdown describes what owners can typically expect when locating the cabin filter.

General Interior Location: Behind or Beneath the Glovebox

In most Audi A5s, the cabin filter is housed in the HVAC unit on the passenger side, roughly behind the glovebox. You do not usually remove the glovebox itself; instead, you go in from the passenger footwell, removing the lower trim under the glovebox to reveal the filter housing.

Once that trim is off, the filter housing is visible as a narrow, rectangular door or cover set into the HVAC box. The filter slides out sideways from this housing, making it accessible while you sit or kneel in the passenger footwell.

Typical Steps to Reach the Cabin Filter

The steps below provide a generic, journalistically summarized walkthrough of how the cabin filter is normally accessed on an Audi A5. These are not a substitute for the official Audi service manual, but they reflect the procedure used by many independent technicians and DIY owners.

The following list explains the common sequence of actions owners or mechanics follow to access the cabin filter on most Audi A5 models.

1. Prepare the car and workspace. Park the car on a flat surface, turn off the ignition, and open the passenger door. Slide the passenger seat back to create room to work in the footwell.
2. Locate the under-dash trim panel. Look beneath the glovebox on the passenger side. You should see a fabric- or plastic-covered panel that hides wiring, lighting, and the HVAC components.
3. Remove the under-dash panel. Depending on model year, this panel may be held by a few screws, Torx fasteners, or plastic clips. Remove these carefully and gently lower the panel. In some models, an interior light or wiring harness may be attached; disconnect if needed.
4. Identify the cabin filter housing. With the panel removed, look toward the center of the vehicle at the HVAC unit. You should see a narrow, rectangular plastic cover—often with arrows or airflow direction markings—secured by clips or small tabs.
5. Open the filter housing door. Release the clips or tabs and swing or slide the cover open. This exposes the edge of the cabin filter, usually a pleated rectangular element.
6. Slide the old filter out. Gently pull the filter straight out toward you. Note the direction of the airflow arrows or orientation markings, as the new filter must be installed the same way.
7. Install the new filter. Insert the replacement cabin filter into the housing, aligning any airflow arrows with the direction indicated on the housing (commonly downward or towards the rear of the car, depending on model).
8. Reattach the housing cover. Close the plastic door over the filter and ensure all clips or tabs engage securely. A loose cover can cause rattles or allow unfiltered air past the element.
9. Reinstall the under-dash panel. Reconnect any wiring or lights, then raise the panel back into place and secure it with its original screws or clips. Confirm that it is snug and that no wiring is pinched.
10. Test HVAC operation. Start the car, switch on the fan at various speeds, and ensure that air flows normally and there are no unusual noises. This confirms the filter is seated properly.

These steps highlight the typical process of accessing the Audi A5 cabin filter; while small differences exist between years and regions, the general layout and approach remain broadly consistent.

Clues Your Cabin Filter Needs Attention

Knowing where the filter sits is only part of the story. The other part is recognizing when it needs to be replaced. A clogged cabin filter can affect comfort and the performance of the HVAC system, and in some cases can strain the blower motor.

The next list outlines common signs that your Audi A5’s cabin filter is overdue for replacement and may warrant an inspection behind the glovebox.

• Reduced airflow from vents. Even at high fan speeds, air volume feels weak, particularly from the central vents, suggesting airflow restriction.
• Persistent musty or dusty smell. Odors when the fan first turns on, or a general stale smell in the cabin, can indicate a dirty or moldy filter element.
• Foggy windows that clear slowly. If the defogger takes longer to clear the windshield, a partially blocked cabin filter may be limiting airflow across the glass.
• Visible debris when inspecting the filter. If you remove the filter and see leaves, black dust, or heavy discoloration, it is likely well past its service life.
• Long intervals since the last change. Exceeding the recommended interval in the owner’s manual—often around 15,000–20,000 km or 1 year, but varying by market and filter type—is a strong indicator that replacement is due.

By watching for these symptoms and understanding the filter’s location, Audi A5 owners can decide when to access the area behind the glovebox and perform a timely replacement.

Differences Between Left-Hand Drive and Right-Hand Drive Models

In left-hand drive markets (such as continental Europe and North America), the cabin filter is normally located behind the front passenger glovebox on the right side of the car. In right-hand drive markets (such as the UK, Australia, and some Asian countries), the configuration is often mirrored, and “passenger side” may instead be the left side of the car. In practical terms, the filter remains behind the glovebox on the side opposite the steering wheel.

While the side of the vehicle may change, the access pattern—removing the footwell trim, locating the HVAC housing, and sliding out a rectangular filter—remains almost identical, with only minor variations in trim design and fasteners.

Why the Cabin Filter Is Placed Behind the Glovebox

Automakers like Audi position the cabin filter where it is close to the HVAC intake but still reachable without major disassembly. The area behind the glovebox on the passenger side offers direct access to the air distribution housing while keeping the filter out of sight and protected from accidental damage.

From a design perspective, this location allows the cabin air to be filtered immediately after it enters the vehicle’s ventilation system, whether drawn from outside or recirculated from inside the cabin. That placement makes it effective for removing airborne contaminants before they spread through the ductwork and vents.

Consulting Official Manuals and Service Information

Although the general location of the cabin filter on an Audi A5 is consistent—primarily behind the glovebox, occasionally with a configuration involving the cowl area on older or specific market versions—the most reliable and precise guidance will always come from the vehicle’s official documentation.

The owner’s manual, service booklet, or manufacturer’s online portal will indicate the service interval, exact location, and any special steps (for example, multiple filters or upgraded “fine dust” or activated charcoal elements) relevant to a particular year, trim, and region.

Summary

On an Audi A5, the cabin air filter is almost always located on the passenger side behind or beneath the glovebox, inside the HVAC housing, with access from the footwell after removing a lower trim panel. On a limited number of earlier or region-specific models, an additional or alternative filter may be found under the hood, beneath the plastic cowl at the base of the windshield. By recognizing this layout and following basic access steps, owners can locate and replace the cabin filter efficiently, improving interior air quality and maintaining the effectiveness of the A5’s climate control system.