Description
Airbag control unit for Citroën C4 Picasso. Fully functional.
Product Overview
This airbag (SRS) control unit is a direct-fit replacement for Citroën C4 Picasso models and is often sought under part numbers 9664217980, 603474700, 6546A8 or 6546A9. Designed to monitor impact sensors and manage airbag deployment, the unit is essential for vehicle occupant safety. Ideal for professional technicians and experienced DIYers who search and order parts by product code.
Technical Information
- Manufacturer: Stellantis / Citroën / Peugeot
- Model: Citroën C4 Picasso
- Product Codes: 9664217980, 603474700, 6546A8
- Other Numbers: 6546A9, NFP
Function
The SRS control unit Continuously Monitors Crash Sensors, Seatbelt Buckle Signals And Airbag Circuits, Decides When To Trigger Airbag Deployment And Stores Crash-Related Fault Data. It Communicates With The Vehicle Network To Coordinate Restraint Actions And To Illuminate The Airbag Warning Light When A Fault Is Present.
How Replacement Works
Replacement Requires Careful Handling: Read And Record Fault Codes Before Removal, Disconnect Battery And Wait To Allow System Capacitors To Discharge, Remove Interior Trim To Access The Unit, Unplug Connectors And Replace Mounting Hardware. After Installation Clear Fault Memory And Perform Full SRS System Checks With A Diagnostic Tool To Confirm Proper Operation. If The Unit Contains Crash Data From A Previous Deployment, It May Be Ineligible For Reuse.
Installation Recommendations
- Always Disconnect The Negative Battery Terminal First And Wait At Least 10 Minutes Before Working On The SRS System.
- Locate The Unit Carefully — Depending On Trim Level It Is Typically Mounted Under The Center Console, Under The Front Passenger Seat Or Behind Interior Trim Panels.
- Use Correct Tools And Torque Values For Fasteners; Protect Connectors From Dirt And Corrosion During Reassembly.
- Use A Professional Diagnostic Tool To Read/Clear Faults And To Perform Post-Installation SRS Tests; Verify That The Airbag Warning Light Is Extinguished.
- If Uncertain About Procedures, Seek A Technician Experienced With Citroën Safety Systems.
Why The Part Most Commonly Fails
Common Failure Causes Include Crash Deployment, Water Ingress Or Moisture Damage, Corroded Or Loose Connectors, Electrical Surges Or Short Circuits, And Internal Component Degradation After Long Service Life. Many Units Become Non-Functional After An Accident Due To Stored Deployment Data Or Internal Damage.
Additional Notes
This Unit Is Frequently Located By Its Part Number During Sourcing. Ensure The Part Number Matches Your Vehicle’s Requirement Before Installation. Proper Diagnostic Verification After Fitting Is Essential For Safety And Roadworthiness.
