For many years now, manufacturers have implemented storage of data, from pre-crash and post-crash events. This information is useful both to the manufacturer and the insurance investigation process. The SRS module stores this data in non-volatile EEPROM storage. Even in the event of a total power failure, the data will remain stored for later retrieval.

Data stored can include many parameters: Vehicle speed and engine load, seat belt information, braking force, time taken to apply the brake pedal, throttle pedal data, Impact force and direction, number of impacts either front or rear, time between multiple impacts, etc.

These modules can also store near-event data, when a collision did not occur, but extreme braking was detected. For this reason, the module is assigned to the vehicle, and the VIN is programmed into the module.

On some vehicles after a crash has occurred, the module can disable the engine from restarting, until the damage can be assessed. This may be as simple as clearing codes on the module, and the engine will start. But some will require crash event memory clearing first. Some manufacturers enable this to be performed diagnostically, via a scan tool, while others require replacing the module.

This has given rise to an industry dedicated to removing this crash data at the board level, by editing the EEPROM binary file. This saves the cost of a module replacement, and the subsequent cost of programming a replacement module.

This was until now. At the Autobiz Helpline, we have recently seen crash event data show up in the other modules, and the functionality has been limited in these control units where the data is present.

One case was on a 2018 VW Polo. Crash data was recorded in the power steering system, and the power assistance was not working. The DTC stored was P1609 (crash shutoff triggered).

The power steering module is known to be an issue after storing crash event data, and we had been unable to delete this error in the past. We attempted to remove the crash data with passthrough programming, but the module failed to recode.

A replacement module was fitted and programmed. The steering column must be removed to replace the J500 module.

In the past, when dealing with crash data, it was just a case of working with the SRS module. Now it has become a more complex process, of erasing the event data from multiple modules.

As seen on some Ford models, storage locations can also include the body control module.

This increases the cost of repairing accident-damaged vehicles. These extra steps need to be taken into consideration when estimating the repair costs.

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