Description
Parking Assist Control Unit Bosch for Citroën and Peugeot vehicles. Front and rear sensors.
This Bosch parking assist ECU is a direct-fit electronic control unit designed to manage front and rear ultrasonic sensors on select Citroën and Peugeot models. Ideal for professional workshops and experienced DIY mechanics, this unit restores parking aid functionality, clears sensor faults and error messages, and helps return the system to reliable operation. The part is frequently searched by OEM numbers, so compatibility and part codes are provided below to make ordering and identification faster.
How It Works
The control unit processes signals from the vehicle’s ultrasonic sensors and interprets object distance to provide audible and visual warnings via the car’s dashboard or infotainment system. It communicates with the vehicle network to coordinate sensor input, parking displays and, where fitted, automated parking functions. Correct installation and intact sensor wiring are essential for accurate detection.
Replacement Procedure
Basic replacement steps for an experienced mechanic or competent DIYer:
- Disconnect the vehicle battery before starting to avoid short circuits.
- Locate the parking assist ECU—commonly fitted in the luggage compartment area or behind interior trim near the rear bumper; access requires removal of trim panels.
- Unplug electrical connectors and mounting fasteners, then remove the old unit.
- Fit the replacement ECU, secure fasteners and reconnect all connectors ensuring pins and seals are undamaged.
- Reconnect the battery and use a diagnostic tool to clear errors and verify sensor operation. The unit may require configuration or coding with manufacturer diagnostic equipment (e.g., Diagbox/Lexia or Bosch diagnostic tools) depending on the vehicle and production variant.
Recommended For Installation
- Required tools: trim removal tools, basic metric sockets/Torx set, multimeter and a compatible OBD diagnostic tool for fault reading and possible coding.
- Skill Level: Suitable for professional mechanics and experienced home mechanics comfortable working with vehicle electrics and interior trim removal.
- Safety Tip: Always disconnect the battery and avoid forcing connectors; check connector seals after reinstall to maintain water protection.
Most Common Failure Reasons
- Water Ingress And Corrosion: Moisture penetration or corrosion at connectors and PCB traces is a frequent cause of ECU failure.
- Impact Damage: Rear or front bumper impacts can damage sensors or the control module mounting and connectors.
- Wiring And Connector Faults: Broken wires, poor grounds or damaged pins lead to intermittent or complete loss of sensor signals.
- Sensor Failures: Faulty individual sensors can overload the system or generate persistent errors that appear to be ECU related.
- Software/Configuration Issues: After replacement, incorrect coding or missing configuration may prevent full operation until properly initialized with diagnostics.
Technical Information
- Manufacturer: Bosch
- Model: Citroën C4 Picasso; Citroen C5 X7; Peugeot 407
- Product Codes: 9663821780; 0263004203; 6590EC
- Other Numbers: 6590EE; 6590CZ; 6590EA; 6590GN; 6590GP
Part numbers are commonly used in searches—entering any of the listed codes will help find the correct unit quickly. Proper diagnosis of sensor lines and connectors before replacement will save time and ensure the new ECU restores full parking assist functionality.
