DTC 907F-49 - Airbag deployed (clear crash data) (crash data stored) airbag control unit fault

What does error code DTC 907F-49 mean?

Error code DTC 907F-49 indicates that the airbag control unit was triggered in a crash and has stored so‑called crash data. For safety reasons, the control unit is then locked, and the airbag system remains inactive until this data is professionally erased.

Technically speaking, this is not a defect but rather a manufacturer‑specified safety feature. Once airbags or seatbelt pretensioners deploy, a permanent entry is recorded in the control unit’s memory, preventing further operation.

This lock ensures that after an accident, the vehicle is thoroughly inspected by professionals and the safety system is fully repaired. As long as error 907F-49 remains active, the airbag warning light stays on continuously, and the system is non‑functional.

How can you recognize error 907F-49?

The primary and most obvious symptom of error 907F-49 is a permanently illuminated airbag warning light on the instrument cluster, which does not turn off even after restarting the vehicle. This condition occurs immediately following an accident in which the safety systems were activated.

Another clear indication is that the airbag system’s fault memory displays this specific code as a permanent, non‑erasable error. Standard diagnostic tools cannot remove this entry, as a specialized procedure is required to reset the crash data.

Meanwhile, the vehicle’s airbag system is completely disabled. In the event of another collision, the airbags and seatbelt pretensioners would fail to deploy, posing a significant safety risk.

Why does error DTC 907F-49 occur?

The sole cause of error code 907F-49 is the activation of pyrotechnic components of the restraint system—such as airbags or seatbelt pretensioners—during a crash. The control unit registers the impact, stores the relevant crash data, and triggers an internal, permanent lock.

This data storage serves to reconstruct the accident and acts as a safety measure to prevent unintended re‑activation without proper inspection and repair of the entire system.

Thus, the error is deliberately set by the system itself and does not indicate a hardware malfunction of the control unit; rather, it reflects a past crash event. Erasing this data is essential for restoring the system to full functionality.

In which vehicles does error 907F-49 occur?

Error code 907F-49 is particularly well known in Renault vehicles. While the principle of storing crash data is common across manufacturers, this specific code is predominantly associated with certain models.

At Airbag24, we repair control units exhibiting this fault pattern, especially for the following model:

Renault: Mégane II (model years 2002–2009). Here, the error is often accompanied by the instruction “Replace ECU after impact” in the diagnostic report.

How is error code 907F-49 professionally repaired?

Professional repair of error 907F-49 involves precisely erasing the stored crash data from the airbag control unit’s memory. At Airbag24, the unit is restored to its factory settings using specialized software, thereby lifting the system lock.

After removing and sending the control unit to Airbag24, the fault memory is first read out to verify error 907F-49 and the stored crash data. A visual inspection is also performed to check for any physical damage to the circuit board or connectors.

The critical step is resetting the internal memory with specialized software. This removes the lock without altering the vehicle‑specific coding. Following this process, the control unit is fully functional and ready for use again.

A final functional test ensures that the control unit operates flawlessly and communication with diagnostic systems has been restored. We provide 2 years' statutory liability for defects on every repair.