Description
Control Unit BSI BSI04EV K04-00 JOHNSON CONTROLS for Citroën C4 Picasso vehicles.
Product Overview
The BSI04EV comfort control unit (BSI) K04-00 manufactured by Johnson Controls is a central body electronics module for Citroën C4 Picasso. It controls and coordinates comfort and convenience functions such as central locking, interior and exterior lighting, wipers, automatic windows, alarm/immobilizer interfaces and CAN communication between vehicle electronic modules. This unit is commonly searched by product codes (for example 9664059080, 1663370780 or K04-00), so listing the correct code helps you find the right replacement quickly.
Technical Information
- Manufacturer: Johnson Controls
- Model: Citroën C4 Picasso
- Product Codes: BSI04EV; K04-00; 9664059080; 9664059080 01; 657064
- Other Numbers: 1663370780; 28119248-3; 28120836-4; BOOT 28120836-4; HARD 28119248-3 C
Function And Typical Symptoms
The BSI is the vehicle’s comfort gateway. It routes CAN messages, manages user inputs (switches, remote keys), supplies power to convenience circuits and interfaces with the immobilizer and instrument cluster. Common symptoms of a faulty BSI include intermittent central locking, non-functioning interior lights, erratic wiper behaviour, failure to respond to key fob, dashboard warning lights or complete loss of some comfort functions.
Replacement Procedure
Replacement should follow a careful, step-by-step approach: disconnect the battery, remove trim panels or the glovebox to access the unit, document and label connector positions, unfasten mounting screws, unplug connectors and extract the module. When installing the replacement reverse the steps, ensure all connectors are fully seated and mount the unit securely. After mechanical installation, the unit usually requires data transfer or coding to match the vehicle’s immobilizer and network configuration.
Installation And Coding – Important
- The Unit Is Used And Is “Paired” With 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 Professional 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
- Always Disconnect The Negative Battery Terminal Before Starting Work.
- Label Connectors And Take Photos To Ensure Correct Reassembly.
- Avoid Static Discharge When Handling The Module; Use ESD Precautions If Possible.
- Verify Battery Voltage Is Stable During Coding; Low Voltage Can Corrupt Module Memory.
- Use Official PSA Diagnostic Tools For Coding Or Cloning To Ensure Full Functionality.
- Check Related Fuses, Grounds And Connectors For Corrosion Before Replacing The Module.
Why This Part Most Often Fails
- Moisture Ingress Or Corrosion Causing Short Circuits Or Connector Failures.
- Voltage Spikes, Poor Jump-Start Procedures Or Faulty Charging Systems Leading To Electronic Damage.
- Age-Related Component Degradation, Cold Solder Joints Or Thermal Stress.
- Poor Previous Repairs Or Aftermarket Modifications That Overload Circuits.
Who Should Fit This Part
This BSI unit is intended for professional workshops and experienced DIYers who have access to appropriate diagnostic tools. Because successful commissioning typically requires cloning or telecoding, workshops equipped with PSA service software will achieve the fastest and most reliable result.
Notes For Buyers
Search By Product Code: Buyers often find the correct replacement fastest by searching the exact part number(s) shown in the technical information. Ensure you match the BSI hardware and software variant (BSI04EV K04-00) to your vehicle’s requirements before installation.
