Audi A3 RS3 8V Wheel ABS Speed Sensor Rear Right O/S WHT003856B

Audi A3 RS3 8V Wheel ABS Speed Sensor Rear Right O/S is an original component from the ABS speed sensor group, designed for precise monitoring of the rotational speed of the rear right wheel. It enables stable operation of the anti-lock braking system, supporting effective braking and the correct functioning of electronic stability control systems.

Specifications and technical data

• SKU: WHT003856B
• Mark: Audi
• Condition: Used
• OEM Part Number: WHT003856B
• Substitutable numbers: WHT003856B, WHT 003 856 B
• Location on the vehicle: Rear, Right
• Category: ABS Speed Sensors

Purpose and function in the braking system

The wheel speed sensor mounted on the rear right axle is responsible for generating a rotational speed signal, which is then analyzed by the ABS controller. Based on this data, the system can modulate pressure in the brake circuit, limiting wheel lock-up during emergency braking and improving vehicle stability on slippery surfaces.

In Audi A3 and RS3 8V generation vehicles, a properly functioning ABS sensor is essential not only for the anti-lock braking system itself but also for cooperating electronic systems, such as traction control or advanced electronic stability control systems. Replacing a faulty component with an original sensor from the same design group allows for the restoration of the entire system's correct operation.

Benefits of using an original Audi sensor

Using an original wheel speed sensor in the Audi A3 / RS3 8V ensures:

• consistency of electrical and signal parameters with the factory ABS controller,
• proper geometric fit to the hub and steering knuckle on the rear right side,
• stable wheel speed reading across the full range of driving speeds,
• reduction of the risk of errors in the controller memory and the illumination of ABS/ESP warning lights.

By maintaining the factory signal characteristics, the sensor works with the existing installation without the need for wiring or software modifications. This solution is particularly beneficial in high-performance cars, such as the RS3, where the braking system operates under more demanding conditions.

Vehicle placement and installation aspects

The presented component is intended for installation on the rear right side of the vehicle. Correct positioning of the sensor relative to the impulse ring is crucial for obtaining a clear signal – the working gap, position, and cable routing should comply with the manufacturer's factory guidelines.

During replacement, it is recommended to:

• thoroughly clean the mounting socket in the steering knuckle or hub,
• check the condition of the impulse ring (magnetic or gear type),
• inspect the electrical wiring for abrasions and connector corrosion,
• clear any potential errors in the controller after completing the installation.

This approach minimizes the risk of recurring faults related to ABS system operation after sensor replacement.

Safe selection of used ABS system components

When choosing a used ABS sensor for an Audi, it is worth paying attention to compatibility with the specific model version and the condition of the connectors and signal cable. A properly selected component allows for maintaining the correct operating parameters of the braking system without the need for costly replacement of entire assemblies. If you want to learn about a detailed list of steps worth taking before purchasing used braking system components, check out the guide Second-hand braking system: how to safely select discs, calipers, and ABS?.

Expanding ABS system upgrades in Audi

If you are planning a comprehensive repair or upgrade of the braking zone in your Audi and need other elements from the same group, such as additional sensors for the other wheels, signal cables, or related anti-lock system components, check the available parts in the Audi ABS speed sensor category.

For a better understanding of how the quick availability of used OEM components affects vehicle downtime in the workshop and repair costs, you can also use the guide material on the impact of used OEM parts availability on repair time. This will make it easier for you to plan the full scope of work on the ABS system in your car.