Mercedes W204 Brake Pump ABS ESP Hydraulic Braking Unit A2049012500 A2044313912

Mercedes W204 Brake Pump ABS ESP Hydraulic Braking Unit is a component from the ABS and ESP System group, responsible for precise pressure control in brake circuits and cooperation with electronic stability control systems. This used hydraulic module allows for restoring the proper operation of the active safety system without the need to invest in a new part. Its black, compact design facilitates integration with the existing installation in a Mercedes vehicle.

Specifications and technical data

• SKU: A2049012500
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A2049012500
• Substitutable numbers: A2049012500, A 204 901 25 00, A2044313912, A204 431 39 12
• Part type: ABS/Stability Control Hydraulic Unit
• Color: Black
• Category: ABS & Stability Hydraulic Units

Purpose and function in the ABS/ESP system

The described hydraulic pump operates within the ABS and ESP System, responsible for generating and modulating brake fluid pressure during emergency braking, ABS operation, and ESP intervention. In practice, this means controlled prevention of wheel lock-up, vehicle stabilization in critical situations, and traction support in various road conditions.

In the Mercedes W204 class vehicle, this module works with wheel speed sensors, the electronic control unit, and the braking system, creating a cohesive safety system. A properly functioning hydraulic pump translates into predictable brake pedal response, stable pressure in the circuits, and effective operation of ABS and ESP functions across the full speed range.

Construction and technical features

The pump body is made in a compact, black housing, adapted for operation in the engine compartment, where variable temperatures and vibrations occur. The hydraulic unit contains channels and valves responsible for rapid pressure switching between individual brake circuits, which enables precise control of braking force on each wheel.

The arrangement of connection ports and mounting points is adapted to the architecture of the braking system in the Mercedes W204, which facilitates installation and minimizes the risk of leaks. The applied design solutions are consistent with the manufacturer's standard, thanks to which the pump maintains compatibility with the factory hydraulic and electronic installation.

Practical application and installation

The used ABS/ESP brake pump is a solution for users who want to restore full efficiency of the safety system while maintaining reasonable service costs. This type of component is used in situations where symptoms such as uneven ABS operation, error messages related to system pressure, or improper operation of the electronic stability control system occur.

During installation, it is recommended to:

• thoroughly bleed the brake system after replacing the hydraulic module,
• verify the tightness of all brake line connections,
• check the correctness of communication with the vehicle's electronics after completing the installation.

Such an approach allows for stable system operation and reduces the risk of repeated service interventions.

Benefits of using an original hydraulic module

Using an original solution designed for the Mercedes W204 ensures proper mechanical and hydraulic fit, as well as compliance with the operating logic of ABS and ESP systems. Thanks to this, the factory braking characteristics and predictable vehicle reactions in emergency situations are maintained.

Compared to replacements, the original hydraulic module offers:

• consistency with the factory controller software,
• appropriate operating parameters of valves and the pump,
• preservation of safety margins designed by the manufacturer.

Expanding the braking system in a Mercedes

If you are planning a comprehensive repair or upgrade of the braking zone in your Mercedes and need other components from the same group, such as pumps, modules, or hydraulic blocks, check the available parts in the ABS and ESP System Mercedes category.

Additional knowledge and operation

When working with advanced safety systems, it is worth understanding the relationships between the braking system, control electronics, and other vehicle components. For drivers interested in a broader perspective on modifications and servicing of components related to driving dynamics, an article describing the impact of components on vehicle performance characteristics may be helpful – more information can be found in the material Performance exhaust system: used manifolds and sports catalytic converters on the road.