What is crash data
Crash Data, Diagnostic Trouble Codes, DTC codes, SRS can be confused and misunderstood especially that they sound very familiar.
In SRS ( airbag and seatbelt systems ) there are 2 memory systems : Crash Event Data and DTC.
1. DTC (Diagnostic trouble codes, sometimes referred to as "codes" ) are typical trouble codes, which if present, can be read with almost any scanner. DTC codes provide data of faulty components, or communication errors between control modules in the vehicle to help a diagnostics technician diagnose the system. Any DTC code can be cleared with a diagnostics scanner after the problem which the DTC code was referring to has been repaired.
2. Crash data ( aka: crash event, collision event, crash data event ) , is the data that is written to the memory chip during the collision. This data includes the state and operation of the vehicle, including speed, buckle of passengers, braking time, and other data. When the vehicle is involved in the accident the crash impact sensors, seat weight sensors and other SRS sensors send data to SRS control module which stores the crash data and determines which airbags and seatbelts to deploy. This data CANNOT be cleared by scanner, and sometimes even not displayed for a scanner diagnostics. Crash Data can only be cleared with special proprietary dealership software and equipment, and can be read with crash forensics software and equipment.