The Engine Control Module (ECM) is found in almost all modern heavy trucks. Data from the ECM is collected and stored in the event data recorder (EDR). Downloading data from the truck’s EDR can provide the accident reconstructionist with information related to the vehicle’s speed, braking, clutch and throttle position, etc. prior to a crash. However, it is important to understand that the purpose of an ECM is to control engine performance, emissions systems, fuel use, etc. It is designed to take “snapshot” data under various scenarios related to the truck’s operation, not record crash data.
Heavy truck ECMs contain four types of data:
- fault data
- historical data
- calibration data
- event data
Each category of data provides different information that can be useful in driver monitoring, vehicle maintenance and repair, and crash investigation. Data recording by each manufacturer’s ECM does not follow a standard protocol and the amount of data generated can vary substantially between manufacturers.
Unlike an airbag control module, the event data recorder in an ECM is not triggered by a crash. Therefore, the analysis and interpretation of the downloaded data from an ECM requires the knowledge and experience to discern which of the numerous reports generated contain information that is related to the crash.
Crash Response has the hardware and software required to download EDR data from most engine manufacturers. Mr. Owen has the experience, knowledge and training to accurately interpret and analyze the ECM data.