BMW F20 LCI Rear ABS Sensor Sender Right O/S 1.5 Diesel B37D15A 6851278

BMW F20 LCI Rear ABS Sensor Sender Right O/S 1.5 Diesel B37D15A is an original wheel speed control system component, designed for installation on the rear right axle of BMW models with a 1.5 diesel engine. Thanks to its factory-matched fit for the specific drivetrain version, it ensures proper cooperation with the ABS system and stable operation of safety systems, such as traction control or electronic stability control. This is a practical solution for professional brake system repairs in modern facelifted BMW 1 Series vehicles.

Specifications and technical data

• SKU: 6851278
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 6851278
• Substitutable numbers: 6851278, 6 851 278
• Location on the vehicle: Rear, Right
• Fuel type: Diesel
• Category: ABS Speed Sensors

Purpose and function of the ABS speed sensor

The presented ABS speed sensor is dedicated to operation in the rear right suspension area of BMW vehicles with a diesel engine. Its task is to precisely read the wheel rotation speed and transmit the signal to the brake system controller, which enables the effective operation of the anti-lock braking system during braking, and also supports vehicle stability functions in difficult road conditions. The component has been designed for consistent cooperation with onboard electronics in versions with the B37D15A unit, which reduces the risk of communication errors and incorrect readings. Using the correct sensor in the appropriate location on the vehicle is crucial for maintaining predictable car behavior during sudden braking or driving on slippery surfaces.

Compatibility with the diesel drivetrain

This sensor model is intended for use with a diesel drivetrain, which is significant for controller configuration and the calibration of driver assistance systems. In vehicles with a diesel engine, the loads transferred to the chassis and braking system differ from those in petrol versions; therefore, using the correct component allows for maintaining the factory operating parameters of the ABS system. Matching the specific engine version facilitates diagnostics and service, and also reduces the risk of repeated interference with the electrical installation. This is particularly important in the case of cars equipped with extensive safety systems, where the accuracy of sensor signals has a direct impact on the operation of many control modules.

Installation characteristics – rear, right side

The sensor is designed for installation on the rear right side of the vehicle, which means that its geometry, cable length, and wiring harness routing are adapted to this specific position. Proper placement on the vehicle facilitates installation and helps avoid cable tension that could lead to insulation damage or signal interference. During replacement, it is recommended to maintain the factory cable routing and ensure the connector is properly seated in the electrical installation socket. Proper positioning of the sensor relative to the pulse ring is crucial for obtaining a stable, repeatable signal, which translates into the effectiveness of the ABS system across the entire speed range.

Component condition and service application

The offered ABS speed sensor is a used part, which makes it an attractive cost-effective alternative while maintaining the manufacturer's original specifications. Such components are often chosen in professional workshops for repairing high-mileage vehicles, where both compliance with the factory installation and rational operating costs are important. Using an original sensor from dismantling allows for reducing the risk of compatibility issues that may occur with aftermarket replacements of ambiguous parameters. This solution is particularly recommended for safety system repairs, where stability and predictability of operation have a direct impact on driving comfort and safety. If you are planning a comprehensive repair or upgrade of the braking zone in your BMW and need other elements from the same group, such as additional sensors, signal cables, or mounting elements, check the available parts in the BMW ABS speed sensor category.

Safety, diagnostics, and technical knowledge

When replacing components responsible for safety, it is worth relying on proven service procedures and reliable technical knowledge. In the case of components sourced from dismantling, it is important to pay attention to the condition of connectors, cables, and the correctness of signal readings during computer diagnostics after installation. For users interested in a broader context of selecting used parts and the impact of original components on vehicle safety, an article describing when it is worth choosing a used element with the manufacturer's logo may be helpful – you can find it here: Spider web on the windshield? Why it is better to choose a used original with the manufacturer's logo during replacement.