Description
Overview
Bosch ABS/ESP control unit with integrated pump supplied together with a short length of wiring harness. Designed for PSA vehicles, this module manages anti-lock braking (ABS) and electronic stability control (ESP) functionality by modulating hydraulic pressure and commanding the pump and valves based on wheel speed and yaw sensor inputs. Often sought by part number (0265950093, 4541W5) for direct fitment or replacement projects.
Key Features and Function
- Controls ABS and ESP functions: prevents wheel lockup and supports vehicle stability under braking or low-traction conditions.
- Includes electric pump and valve block to modulate hydraulic pressure to individual wheels.
- Delivered with a section of wiring harness to simplify electrical connection during replacement.
- Commonly identified and searched by OEM Bosch and PSA codes for faster sourcing and compatibility checks.
Compatibility
Primary fitment: Peugeot 307 CC and Citroën C4 (PSA platform). Always verify compatibility by matching your vehicle VIN and the unit part numbers before purchase. This module is typically used on models sharing the PSA braking system architecture from the same production years.
Symptoms Of A Failing Module
- ABS or ESP warning lamp illuminated on the instrument cluster.
- Intermittent or permanent loss of ABS/ESP functionality, longer braking distances or wheel lock under hard braking.
- Unusual noises from the pump motor or irregular brake pedal feel after activation.
Common Causes Of Failure
Failures are commonly caused by electrical faults (corroded connectors, wiring damage), internal hydraulic contamination, water ingress, or wear of the pump motor and solenoids. Age, brake fluid contamination and thermal cycling increase the likelihood of malfunction.
Replacement And Installation Notes
Recommended steps for professional mechanics or experienced DIYers:
- Disconnect the negative battery terminal before starting to avoid electrical damage.
- Access the ABS/ESP unit by removing relevant trim or engine bay covers; support brake lines and prepare to catch fluid when disconnecting lines.
- Unbolt the control unit and carefully disconnect the electrical connectors and brake pipes. Label lines for correct reassembly.
- Replace the unit, reconnect wiring harness, reinstall brake lines, then perform a full system bleed to remove air from the hydraulic circuit.
- After mechanical installation, a diagnostic tool is usually required to clear codes and to perform any required ECU coding or unit adaptation so the vehicle recognises the new module.
- Inspect connectors and related wheel speed sensors when replacing the module; underlying sensor faults can cause repeated failures or codes.
Technical Information
- Manufacturer: Bosch
- Model: Peugeot 307 CC; Citroen C4
- Product Codes: 0265950093; 4541W5
- Additional Numbers: 4541W6; 265950093; NFP
Notes For Buyers
Part numbers are often used as the primary search term by mechanics and DIY customers — check the unit code on your existing module before ordering. Installation typically requires a scan tool capable of ABS/ESP diagnostics and adaptation. If in doubt, consult a qualified technician for correct coding and bleeding procedure to restore full braking system performance.
