A Guide to the ABS Wheel Speed Sensor on Your 2009-2016 Audi A4
Understand why your ABS and traction control lights are on and how to choose the right replacement sensor for your A4.
- A dashboard with ABS, ESC, and Parking Brake lights is the number one sign of a failed sensor.
- Before replacing the sensor, inspect the magnetic ring on the wheel bearing for damage or rust, a common issue on this A4.
- Use a diagnostic tool to confirm which specific wheel sensor has failed before buying parts.
- Bosch and Hella are top-tier aftermarket brands, while Febi offers a good balance of cost and quality.
Is Your Audi A4 Dashboard Lit Up Like a Christmas Tree?
If you own a 2009-2016 Audi A4 (known as the B8 generation), a sudden array of warning lights on your dashboard is a common sign of a failing ABS wheel speed sensor. Typically, you'll see the ABS, Electronic Stability Control (ESC/ESP), and sometimes the parking brake and Tire Pressure Monitoring System (TPMS) lights all come on at once. This happens because all these safety systems rely on the speed sensors to work. When one sensor fails, the car's computer disables them as a precaution.
🎬 Watch: Diagnosing dashboard warning lights and replacing the sensor.A Critical Note: Sensor vs. Wheel Bearing
On this specific generation of Audi A4, the problem isn't always the sensor itself. Each wheel bearing has a magnetic ring built into its seal, which the sensor reads. Over time, this ring can get damaged by rust, debris, or wear. If the ring is the problem, a new sensor won't fix it. The entire wheel bearing will need to be replaced. 🎬 See this walkthrough for replacing a front wheel bearing. A visual inspection of the wheel bearing's magnetic ring is essential before you buy a new sensor.
Choosing the Right Aftermarket ABS Sensor
You don't need to buy a sensor from the Audi dealer to fix your car. Many aftermarket companies make high-quality replacements. Here’s how they generally stack up for your A4:
- Premium Brands (OEM Quality): Brands like Bosch, Hella, and Delphi are often the original equipment manufacturers for Audi. Choosing one of these is the closest you can get to the factory part. They offer the best reliability and fit, but are also the most expensive aftermarket option.
- Reputable Aftermarket Brands: Companies like Febi, Beck/Arnley, and Standard Ignition (SMP) offer a great balance of quality and price. They are trusted in the industry and produce reliable parts that are a solid choice for most owners.
- Economy Brands: Brands such as URO Parts, Holstein, and Vemo are budget-friendly options. They can be a good choice if cost is your main concern. Holstein often includes new mounting hardware, which is a nice bonus. However, the long-term durability might not match that of the premium brands.
| Item | Estimated Cost |
|---|---|
| New OEM Part (Dealer) | $130 - $180 |
| New Aftermarket Part | $29 - $142 |
| Shop Labor | $95 - $150 |
| Total (Aftermarket Part at Shop) | $124 - $292 |
Pro Tip: Get a Proper Diagnosis
Before buying any parts, get the car scanned with an Audi-specific tool like VCDS (VAG-COM). A generic code reader might just say "ABS fault," but a better scanner will tell you exactly which wheel sensor is failing (e.g., "G44 - Rear Right Wheel Speed Sensor"). This prevents you from replacing the wrong part.
🎬 Watch: How to scan and reset ABS codes yourself.Frequently Asked Questions
Can I replace the ABS sensor myself?
Yes, this is a very DIY-friendly job for someone with basic tools. The sensor is held in by a single bolt (usually a 5mm hex). The main challenge is that the old sensor can get stuck and break during removal, so be prepared to carefully extract the pieces if that happens.
Do I need to replace all four sensors at once?
No. You only need to replace the sensor that has failed. A proper diagnostic scan will identify the specific sensor that needs attention.
Are the front and rear sensors the same? What about left and right?
No, they are often different. The front, rear, left, and right sensors can have unique part numbers and are not always interchangeable. Double-check the part number for the exact corner you are replacing.
Were there any recalls for this issue?
There were no specific recalls for the ABS wheel speed sensors on the 2009-2016 A4. However, there were recalls for the ABS *control module* on some 2009 models, which can cause similar warning lights. There is also a Technical Service Bulletin (TSB) that notes that dirt and debris on the sensor or wheel bearing ring can cause false readings.
Helpful Videos
Technical Specifications
OEM Part Numbers: 4E0927804F 4E0927803F WHT003860 WHT003861 WHT003862 WHT003863
The sensor is a 2-pin Hall effect sensor that mounts to the wheel knuckle with a single bolt.
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: