Guide to Replacing the Horn on a 2004-2016 Audi A4 Quattro
If your A4's horn sounds weak or is completely silent, this guide will help you diagnose the problem and choose the right replacement part.
- A weak or 'scooter-like' sound almost always means one of the two horns has failed.
- The horns are located behind the front bumper, so replacement requires removing the bumper cover.
- You must identify whether the failed part is the high-tone (passenger side) or low-tone (driver side) horn before ordering a single replacement.
- If the horn is silent and the airbag light is on, the problem is likely the clock spring, not the horn itself.
Is Your Audi A4 Horn Failing?
The most common sign of horn trouble in the 2004-2016 A4 Quattro is a change in sound. Because the horns are mounted low and at the front of the car, they are exposed to water and road salt, which can cause one of the two units to fail. If your horn suddenly sounds weak, high-pitched, or like it belongs on a scooter, it almost always means one of the two horns has stopped working.
Diagnosing the Issue Before You Buy
Before spending money on parts, a few simple checks can help you confirm the problem:
- Check the Fuse: Look in your owner's manual to find the horn fuse. If the metal strip inside is broken, replace it. If the new fuse blows right away, you have a short circuit in the system.
- Listen for the Relay: Have a friend press the horn while you listen for a 'click' from the fuse box area. 🎬 Watch: Locate the horn fuse and relay on B8 models A click usually means the relay is working, and the problem is further down the line (wiring or the horn itself). No click could point to a bad relay or an issue in the steering column.
- Identify the Failed Horn: Your A4 has a high-tone horn (passenger side) and a low-tone horn (driver side). With a helper, stand in front of the car while the horn is pressed to hear which side is silent. This tells you which part to order.
- Consider the Clock Spring: If your horn is completely silent and the airbag warning light is on, the problem is likely a failed clock spring in the steering column, not the horns themselves.
Choosing the Right Aftermarket Horn
When replacing a failed horn, you have the choice between Original Equipment Manufacturer (OEM) parts and aftermarket parts. OEM horns are expensive for what they are. Aftermarket brands offer a more affordable solution without a significant drop in quality.
Hella is a well-known and popular aftermarket choice for European cars, including Audi. Many owners find their tone to be sharper and more attention-grabbing than the stock horns. While some tests show they aren't necessarily louder in decibels unless wired with a dedicated relay, their piercing tone is effective on the road. For a direct replacement, a Hella dual-tone kit is a reliable and cost-effective option.
Cost of Horn Replacement: 2004-2016 Audi A4 Quattro
| Part Type | Estimated Part Cost | Notes |
|---|---|---|
| New Aftermarket (Hella) | $71.84 - $73.17 | Often sold as a complete high/low tone kit. |
| New OEM | $200 - $220 | Price for a single horn unit can be high. |
| Used OEM | $20 - $65 | A budget option, but inspect for corrosion before buying. |
| Shop Labor | $135 - $250 | Cost is mainly for removing and reinstalling the front bumper. |
Replacement Overview
Replacing the horns on an A4 from these model years is a moderately difficult job because they are located behind the front bumper cover. Access requires removing the bumper, 🎬 See this walkthrough for removing the front bumper cover which can be time-consuming.
Once the bumper is off, the horns are easily visible on the radiator support or crash bar. The process is to simply unplug the electrical connector, unbolt the old horn, and install the new one. 🎬 Watch: Step-by-step horn replacement on a 2009 Audi A4 Because of the labor involved in accessing them, some owners choose to replace both horns at the same time, even if only one has failed.
Frequently Asked Questions (FAQ)
Why does my Audi's horn sound weak or high-pitched?
This is the most common symptom and it almost always means that one of your two horns (usually the low-tone one) has failed due to water or corrosion. Your A4 uses a dual-tone system, and when one fails, you only hear the remaining horn.
Do I need to replace both horns at once?
No, you only need to replace the one that has failed. However, since accessing the horns requires significant labor (removing the bumper), and the second horn may be near the end of its life, many owners choose to replace them as a pair to avoid doing the job twice.
Are there any recalls for the horn on my A4?
Searches of the National Highway Traffic Safety Administration (NHTSA) database did not show any specific safety recalls for horn failure on the 2004-2016 Audi A4.
What is the difference between the high-tone and low-tone horn?
They are two separate parts that produce different frequencies. The low-tone horn is typically on the driver's side (part numbers often end in 221 or 221A), and the high-tone horn is on the passenger's side (part numbers often end in 223 or 223A). You must order the correct one if replacing just one.
Helpful Videos
Technical Specifications
OEM Part Numbers: 4F0951221A 4F0951221 4F0951223A 4F0951223
System Type: Dual-tone (High and Low Frequency). Location: Front of vehicle, behind bumper cover, mounted to radiator support/crash bar.
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 A4 Quattro: