Description
Overview
The Valeo BSI J04-00 ECU is a Body Control Module (BSI) intended for PSA platform vehicles such as the Peugeot 307. This unit manages comfort and convenience functions across the vehicle, including central locking, interior lighting, wipers, and certain communication with other electronic control units. The module is often referenced by its product number and related cross-reference codes, which makes searching by part number common among mechanics and DIY enthusiasts.
Key Functions And Common Failures
The BSI acts as the car’s central comfort and body management unit: it controls door locks, interior lights, alarm inputs, switch logic, and interfaces with immobiliser and key recognition systems. Typical reasons for BSI failure include water ingress or moisture, connector corrosion, voltage spikes or poor battery/alternator performance, and electrical short circuits. Symptoms of a failing BSI can include intermittent central locking, lighting faults, loss of communication with other control units, or immobiliser/key recognition issues.
Installation And Practical Notes
Replacement is straightforward for experienced technicians but requires attention to safety and vehicle security: disconnect the negative battery terminal before starting to avoid short circuits or unintended airbag/immobiliser triggers. Access generally requires removal of interior trim around the steering column and lower dashboard to reach the BSI housing. After fitting the unit and reconnecting connectors, the module usually requires configuration or programming with a compatible PSA diagnostic tool (for example DiagBox/Lexia or equivalent) to synchronise immobiliser data and vehicle options. If keys or immobiliser data must be rematched, additional diagnostic steps and key programming may be necessary.
Service Life And Replacement Advice
Life expectancy depends on vehicle environment and electrical stability. Vehicles exposed to moisture, poor maintenance, or unstable power supplies are more likely to experience earlier BSI faults. If a fault recurs shortly after replacement, inspect wiring harnesses, grounds, battery condition, and fuses for underlying causes before replacing the BSI again.
Technical Information
- Manufacturer: Valeo
- Model: BSI J04-00
- Product Codes: 9651197680
- Additional Numbers: 9651196980, 6580J0, 6580HS, 6580N0, 6580GW
Compatibility And Verification
This BSI is listed for use on Peugeot 307 models. Compatibility can vary by production year and vehicle equipment level; some PSA Citroën vehicles that share the same platform may use compatible units. Always verify the part number on the existing unit and cross-check vehicle identification (VIN) or wiring/connectors before ordering or installing.
If you are a professional mechanic or an experienced DIYer, this Valeo BSI J04-00 unit provides a direct replacement path for common PSA body control faults. If unsure about programming or immobiliser synchronisation, consult a qualified diagnostic technician to complete the final configuration.
