What is airbag crash data?
Every vehicle has an airbag control unit — commonly called an SRS ECU (Supplemental Restraint System Electronic Control Unit). This module constantly monitors crash sensors throughout the vehicle. When a collision occurs that meets the deployment threshold, the ECU fires the airbags and seatbelt pretensioners — and simultaneously records detailed crash data into its internal memory.
This crash data typically includes the timestamp of the event, G-force readings from all crash sensors, which airbags and pretensioners were deployed, and a fault code log of what happened. This information is permanently stored in the ECU's non-volatile memory (EEPROM or flash memory), and it cannot be erased by disconnecting the battery, clearing OBD codes, or replacing the airbag bags themselves.
Why does the airbag warning light stay on?
After a collision, even once the vehicle is mechanically repaired with new airbag bags, new seatbelt pretensioners, and new side curtains, the airbag warning light on the dashboard will stay on permanently. This is because the SRS ECU still holds the crash data in memory. The ECU "knows" it deployed airbags and will not allow the system to arm again until that data is cleared.
Many workshops and technicians attempt to clear the fault codes using an OBD diagnostic scanner. While this may temporarily turn off the light for a few drive cycles, the underlying crash data in EEPROM remains. The light returns — and more importantly, the airbag system does not function correctly because the ECU is still in post-crash lockout mode.
How is airbag crash data cleared?
Clearing airbag crash data requires reading and rewriting the ECU's internal EEPROM or flash memory directly. This is not possible via the OBD port — it requires physically connecting to the ECU chip, reading the binary file, finding and zeroing the crash data sectors, then writing the corrected file back.
There are two main approaches used by professional workshops:
1. Hardware programmer (on-bench): The ECU is removed from the vehicle, opened, and a chip programmer (such as a MiniProg or similar BDM programmer) is connected directly to the microcontroller. The binary is read, edited, and rewritten. This requires experience with electronics and knowledge of the specific ECU architecture.
2. Online file service (recommended): The ECU is removed and read using a bench programming tool. The binary file is then uploaded to an online service like EPJ Airbag Solutions. Within hours, a corrected reset file is returned — ready to write back to the ECU. No chip-level electronics knowledge is required.
Is it legal to reset airbag crash data?
Yes — when done as part of a legitimate vehicle repair. Airbag ECU crash data reset is a standard repair procedure performed by professional workshops, insurance repair centres, and salvage specialists worldwide. The goal is to restore a properly repaired vehicle to full working condition with a functioning airbag system.
Resetting crash data on a vehicle that has not had the airbags and pretensioners physically replaced is dangerous and irresponsible. Our service is intended for professional workshops performing complete accident repairs.
What does EPJ Airbag Solutions support?
We support over 8,000 airbag ECU part numbers from Bosch, Continental, Autoliv, TRW, Hyundai Mobis, Honda, Ford, BMW, Fiat, PSA and many more manufacturers. The process is fully online — upload your binary file through our secure portal and receive the reset file back within hours.