Description
BSI Control Unit BSI04EV K04-00 JOHNSON CONTROLS for Citroën C4 Picasso vehicles
Overview
This used BSI (Body Systems Interface) module BSI04EV K04-00 by Johnson Controls is designed for Citroën C4 Picasso models and controls multiple comfort and body functions. Commonly referenced by part number 9664059080 01, this unit manages lighting, central locking, wipers, interior electronics and communicates with other vehicle modules via the CAN network. Ideal for professional workshops and experienced DIY mechanics who need a direct replacement or a donor unit for cloning or reprogramming.
Technical Information
- Manufacturer: Johnson Controls (supplied to Stellantis – Citroën/Peugeot)
- Model: Citroën C4 Picasso
- Product Codes: BSI04EV K04-00; 9664059080 01
- Additional Numbers: 657064; 1663370780; BOOT 28120836-4 (bootloader); HARD 28119248-3 C (hardware version)
Function And Typical Faults
The BSI is the central comfort and body control unit that supervises and coordinates interior electronics such as central locking, interior lighting, indicator logic, wipers, window control, alarm and some gateway functions to the vehicle CAN buses. Failures usually present as non-responsive locks, intermittent lighting issues, instrument cluster errors, repeated fault codes or complete loss of certain comfort functions. The most common causes of BSI faults are moisture ingress and corrosion, electrical surges or poor battery/alternator voltage, connector corrosion, and occasional firmware corruption after power interruptions.
Replacement Procedure
- Safety First: Always disconnect the negative battery terminal before starting work to avoid short circuits and protect the module.
- Access: The BSI is typically located behind the dashboard or glovebox area on Citroën C4 Picasso models; remove the necessary trim panels to reach it.
- Disconnect: Carefully unplug all wiring connectors and remove mounting fasteners. Inspect connectors and wiring for corrosion or damage.
- Install: Fit the replacement unit, secure fasteners and reconnect all plugs. Reassemble trim panels in reverse order.
- Coding/Initialization: After physical replacement, the unit usually requires cloning or programming to the vehicle (see installation and coding notes below).
Installation And Coding – Important
- The unit is used and is “paired” to the original vehicle (VIN/PIN/keys).
- Options for commissioning:
- Cloning data from the old unit (EEPROM/Flash) – after cloning the unit is plug and play.
- Virginization and subsequent initialization/telecoding via DiagBox (or online) + key adaptation.
- Recommended to be performed by a technician with PSA service equipment (DiagBox/Lexia/PP2000).
- Before removal/installation always disconnect the battery and follow the manufacturer’s procedure to avoid damaging the unit.
Recommendations For Installation
Work in a dry, static-free environment. Inspect connector pins and housing for corrosion or bent pins and clean as needed before fitting. If possible, transfer immobilizer-related components only under guidance of a diagnostic tool. Use correct torque on fasteners and avoid forcing connectors. If you are not experienced with module cloning or telecoding, arrange for programming with PSA diagnostic tools to restore full functionality.
Why This Part Typically Fails
BSI units most often fail due to moisture ingress leading to corrosion, exposure to voltage spikes from jump-starts or faulty alternators, and progressive connector degradation. Inadequate sealing behind the dashboard or previous water leaks accelerate failure. Firmware corruption can occur after sudden power loss while the unit is writing data.
Suitable For
Direct fit for Citroën C4 Picasso vehicles referencing part number 9664059080 01 and compatible BSI04EV K04-00 modules. Ideal for mechanics replacing a failed BSI where cloning or reprogramming services are available.
