Description
Airbag Control Unit for Peugeot 406
Description
This airbag control unit (SRS/Airbag ECU) is intended for Peugeot 406 models. The unit monitors impact sensors and seatbelt buckle switches, decides on airbag and pretensioner deployment in the event of a collision, and stores diagnostic and crash-related fault codes. It is commonly searched for by OEM part numbers and alternative codes, making it easy for mechanics and DIY enthusiasts to find the correct replacement.
Compatibility
Designed for Peugeot 406 vehicles (various body types produced in the model years). Compatible references include the OEM codes listed below—searching by these numbers (9638592580, 550725200, 6545JP, 6545JQ, 6545JL, 6545JN) helps locate the exact unit required for a given vehicle.
Technical Information
Manufacturer: Stellantis / Peugeot
Model: Peugeot 406
Product Codes: 9638592580, 550725200
Other Numbers: 6545JP, 6545JQ, 6545JL, 6545JN
How It Works And Why It Fails
The airbag control unit constantly evaluates inputs from crash sensors, accelerometers, seat occupancy and belt buckle sensors. On detecting a qualifying impact, it triggers airbags and pretensioners in a fraction of a second. Units most commonly fail after a collision (stored crash data makes the unit inoperable without reset or replacement), due to water or moisture ingress, corrosion of connectors, or electrical faults caused by improper battery jumps or short circuits. Internal electronic component failure or damage after deployment are also frequent causes.
Replacement And Installation Recommendations
Replacing the airbag control unit requires careful attention to safety and vehicle electronics. Recommended steps for experienced mechanics or competent DIYers:
- Disconnect the negative battery terminal and wait at least 10 minutes to allow SRS capacitors to discharge.
- Remove the necessary trim or console panels to access the SRS control unit (often located under the center console or under a seat, depending on the vehicle configuration).
- Unplug connectors carefully—inspect pins and wiring for corrosion or damage and repair as needed before installing the new unit.
- Install the replacement unit, reconnect wiring and battery, then clear fault and crash memory using appropriate PSA diagnostic equipment (Diagbox/PP2000 or an equivalent capable scanner). A diagnostic tool is typically required to reset the unit and ensure proper SRS system operation.
Work Should Be Performed With Proper Tools And Safety Precautions. If You Are Not Confident With SRS Systems, Use A Qualified Workshop.
Common Signs That The Unit Needs Replacement
Typical symptoms indicating a faulty airbag control unit include the airbag warning lamp illuminated continuously on the dashboard, persistent SRS fault codes stored in the memory, non-deployment indication after a collision, or visible water damage to the unit/connectors. After an accident, even if airbags did not deploy, the control unit may record an event that prevents normal operation until cleared or replaced.
Why Choose This Part
Mechanics and DIYers searching by part number will find this unit under the listed OEM codes. It is suitable for repairs where the SRS control unit is identified as the root cause of airbag system faults. Including correct part codes in your search increases the likelihood of a direct fit and faster troubleshooting.
Reference Codes
Stellantis Citroen Peugeot; 9638592580; 550725200; 6545JP; 6545JQ; 6545JL; 6545JN
