Description
BSI Control Unit VALEO BSI-BOITE B6 for CITROEN XSARA PICASSO
HARD: PR4
SOFT: V8.2
The Valeo BSI-BOITE B6 is a direct-fit Body Systems Interface (BSI) used on Citroën Xsara Picasso vehicles. This compact comfort/control module centralises vehicle body electronics — managing lighting, central locking, wipers, windows, dashboard indicators and communication with other ECUs. Commonly referenced by part numbers such as 9642409480 and 73002512, the unit is suited for professional workshops and experienced DIY mechanics who replace and commission vehicle control modules.
Function And Application
The BSI (Body Systems Interface) acts as the central gateway for many convenience and safety functions. It controls interior and exterior lighting logic, central locking, intermittent wiper control, power windows, horn, alarm and interfaces with the immobiliser. It also handles CAN bus messages between body systems and engine or gearbox ECUs. Replacing a faulty BSI restores correct behaviour of these systems and eliminates erratic electrical faults often caused by a failing unit.
Replacement Procedure
Location: Typically mounted behind the dashboard on the driver side, often near the fuse box or under the steering column trim. Exact position can vary by model year.
Basic Replacement Steps:
- Disconnect the negative battery terminal before any work to avoid short circuits and protect the electronics.
- Remove required trim panels to access the BSI and unscrew its mounting fasteners.
- Carefully unplug all electrical connectors—note connector locks—and remove the unit.
- Install the replacement unit, secure mounting fasteners and reconnect all plugs.
- Proceed with the required commissioning: cloning or coding (see Installation And Coding – Important below).
- Verify all controlled functions (locks, lights, wipers, windows, dashboard warnings) and perform a road test.
Installation And Coding – Important
– The Unit Is Used And Is Paired With The Original Vehicle (VIN/PIN/Keys).
– Options To Put The Unit Into Service:
1) Cloning Data From The Old Unit (EEPROM/Flash) – After Cloning The Unit Is Plug And Play.
2) Virginization And Subsequent Initialization/Telecoding Via DiagBox (Or Online) + Key Adaptation.
– Recommended To Be Performed By A Specialist With PSA Service Equipment (DiagBox/Lexia/PP2000).
– Always Disconnect The Battery Before Removal/Installation And Follow The Manufacturer Procedure To Avoid Damaging The Unit.
Technical Information
- Manufacturer: Valeo
- Model: Citroën Xsara Picasso
- Product Codes: 9642409480, 73002512
- Additional Numbers: 73005812, 658038, 658072
- BSI Type: B6
- Hardware: PR4
- Software: V8.2
- Category: BSI – Comfort Modules / Electrical Components / Control Units
Recommendation For Installation
Perform coding or cloning in a workshop environment with diagnostic tools. Use PSA-specific tools (DiagBox/Lexia/PP2000) for reliable initialization and key adaptation when not cloning. Handle connectors with care, avoid forcing pins, and ensure battery voltage is stable during programming. Protect the unit from moisture and electrostatic discharge while handling.
Why This Part Fails Most Often
Common failure causes include water ingress or corrosion (especially in vehicles with leaks or aged seals), electrical surges from jump-starts or faulty charging systems, repeated short circuits, and internal component aging. Symptoms often begin as intermittent faults: central locking failures, erratic lighting, non-functioning wipers or windows, dashboard warning lights, or complete loss of convenience functions. Early diagnosis and repair prevent secondary faults in other modules.
Suitable For Professionals And Experienced DIYers Looking For A Direct Replacement BSI For Citroën Xsara Picasso Models. Searchable By Part Numbers 9642409480 And 73002512 For Fast Identification.
