2017-2024 Audi A4, S4, A5, S5 & RS5 Driver-Side Fuse Box Guide
A complete guide to diagnosing, replacing, and understanding the driver-side dashboard fuse box (Part No. 8W0941824AQ) for the Audi B9 platform.
- This guide is for the driver-side dashboard fuse box only; these vehicles have multiple fuse boxes.
- The fuse box housing itself (8W0941824AQ) does NOT require programming or coding, making a used part a great value.
- The most critical step during replacement is to transfer all fuses from the old box or use a VIN-specific diagram to populate the new one. Failure to do so will cause vehicle features to not work.
- Inspect for signs of water damage (corrosion), which is a common cause of failure often linked to clogged sunroof drains or other cabin leaks.
Identifying Your Fuse Box
This guide is for the fuse box, also known as a fuse carrier, located on the driver's side of the dashboard in the 2017-2024 Audi A4, S4, and 2018-2024 Audi A5, S5, and RS5. To access it, you typically need to open the driver's door and pry off the end panel of the dashboard. These vehicles have other fuse boxes located in the passenger's footwell, the engine bay, and the trunk, so it's crucial to identify the correct one before proceeding with any diagnosis or replacement. 🎬 Watch: Audi A5 and S5 fuse box locations and diagrams This specific fuse box housing is generally identified by OEM part number 8W0941824AQ.
Symptoms of a Failing Fuse Box
A problem with the fuse box itself, rather than just a single blown fuse, can cause confusing and widespread electrical issues.
- Multiple Unrelated Electrical Failures: You might experience issues with the radio, power windows, interior lights, and climate controls all at once. This happens because the main power feeds within the box may be compromised.
- Melting Plastic or Burning Smell: A strong indicator of a serious problem is the smell of burning plastic or visible melting on the fuse box housing. This points to a significant short circuit or a loose connection causing high resistance and heat.
- Loose Fuses: If fuses no longer fit snugly in their slots, it suggests the internal terminals are damaged or have lost their tension. This can cause intermittent power to circuits as the fuse makes and loses contact.
- Corrosion: Green or white crusty deposits on the fuse terminals or the box itself are a clear sign of water intrusion. Water damage is a common cause of failure and can lead to unpredictable electrical behavior.
Pro Tip: Many electrical issues are caused by a single blown fuse, not a faulty fuse box. Always check for and replace individual blown fuses before condemning the entire box. 🎬 See: How to diagnose common fuse box problems A blown fuse will have a broken wire inside or look burnt.
Known Issues, TSBs, and Recalls
Water Damage from Clogged Drains or Leaks
The most significant known issue that can lead to fuse box failure is water intrusion into the cabin. While the driver-side dash fuse box is less exposed than components on the floor, severe leaks can still cause problems. Water can enter due to:
- Clogged Sunroof Drains: This is a very common problem. Drains get blocked with debris, causing water to overflow from the headliner and run down the A-pillars, potentially reaching the dash-end fuse box. 🎬 Watch: How to clean clogged sunroof drains
- Dislodged Grommets: A grommet in the engine bay's firewall, such as for the hood release cable, can become dislodged, allowing water to enter the driver's footwell area.
- Improperly Sealed Windshields: After a windshield replacement, a poor seal can allow water to leak into the dashboard area.
There are no specific recalls for this fuse box itself, but several recalls exist for related wiring and electrical components on these models. For example, recall 97EU involved missing abrasion protection on rear light wiring harnesses. Always check your vehicle's VIN on the NHTSA or Audi websites for any open recalls.
Programming and Configuration Requirements
No Programming Required
The fuse box housing (part number 8W0941824AQ) is a non-intelligent part. It is a physical assembly of plastic and metal contacts. It does not contain any software and does not require any programming, coding, or flashing after installation. This makes it an excellent candidate for a used replacement part.
Warning: While the box itself isn't programmed, its configuration is critical. The specific fuses installed depend entirely on your vehicle's factory-installed options. A car with heated seats and adaptive cruise control will have more fuses than a base model.
Buying a Used Fuse Box: What to Look For
A used OEM fuse box is a smart, cost-effective choice. Since it's not a moving part and doesn't have software, a clean, undamaged unit from a donor vehicle is functionally identical to a new one.
- Verify the Part Number: Ensure the housing matches part number 8W0941824AQ.
- Inspect for Physical Damage: Check for any signs of melting, cracks, or broken mounting tabs. Look closely at the fuse terminals for any discoloration from heat.
- Check for Corrosion: This is the most important check. Avoid any fuse box that has white or green powder, rust, or any signs of water damage.
- The Fuse Transfer Rule: Do not assume the fuses in the used box are correct for your car. You MUST either transfer every fuse from your old box to the new one or use a fuse diagram specific to your vehicle's VIN to populate the replacement box correctly. Failure to do this will result in some features not working.
Cost of Replacement
| Part Type | Price Range |
|---|---|
| New OEM (Part No. 8W0941824AQ) | $20 - $45 |
| Used OEM | $20 - $50 |
| New Aftermarket | Not commonly available |
| Shop Labor Cost | $100 - $200 |
Frequently Asked Questions (FAQ)
Does this fuse box need to be programmed to my car?
No. The fuse box housing is a non-electronic part and does not require any programming, coding, or dealer visit for installation. However, you must ensure the correct fuses are installed for your vehicle's options.
Where is this fuse box located?
It is located on the driver's side of the dashboard, accessible after opening the driver's door and removing the side trim panel of the dash.
Some of my car's features stopped working after I replaced the fuse box. Why?
You likely did not populate the replacement fuse box correctly. Not all fuse slots are used on all cars. You must transfer the fuses from your original box or use a VIN-specific fuse diagram to install the correct fuses in the correct locations for your car's features to work.
Can I replace just a single blown fuse instead of the whole box?
Yes, absolutely. In most cases, an electrical problem is caused by a single blown fuse. The entire fuse box should only be replaced if it is physically damaged, melted, or corroded from water damage.
Helpful Videos
Technical Specifications
OEM Part Numbers: 8W0941824AQ 8W0941824AC
Houses blade-type automotive fuses. Configuration is dependent on vehicle options. Located at the driver's side end of the dashboard.
We Have This Part in Stock
The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.
- Audi A5:
- Audi RS5:
- Audi S5:
- Audi A4:
- Audi S4:
- 🎬 Helpful Videos
- 🛍️ Shop This Part
- Identifying Your Fuse Box
- Symptoms of a Failing Fuse Box
- Known Issues, TSBs, and Recalls
- Water Damage from Clogged Drains or Leaks
- Programming and Configuration Requirements
- No Programming Required
- Buying a Used Fuse Box: What to Look For
- Cost of Replacement
- Frequently Asked Questions (FAQ)
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