Since the mid to late 1990’s, many of the heavy vehicle engine manufacturers started incorporating Event Data Recorder (EDR) capabilities into their engine control modules (ECM). Originally designed for engine and performance diagnostics, the EDR grew in importance and value for performance diagnostics with the increasing fuel economy requirements mandated since 2007.
Similar to passenger vehicle EDR’s, the heavy vehicle EDR’s were not initially designed for accident reconstruction or continuous recording (i.e. airplane and train EDRs). But, unlike passenger vehicle EDR’s, which rely on airbag control modules or supplemental restraint modules for incident data recordings, heavy vehicle EDR’s rely on ECMs and other diagnostic and reporting modules within the heavy vehicle for incident data recording.
Also unlike passenger vehicle EDR’s (produced since 2012), heavy vehicle EDR’s have no regulatory requirements that mandate any standardization of incident data recording. However, many of the heavy vehicles have adopted many similar communication, software, and hardware protocols. Some of the heavy vehicles may have incident data which is retrievable either through publicly available tools and software, or through certain vendors specified by the engine manufacturer.
If so enabled, heavy vehicle EDR’s may contain one or more of the following:
- Hard braking data
- Last stop data
- Fault codes
- Trip data
- Diagnostic snapshot data
Additionally, some heavy vehicles may contain integrated or standalone modules or systems designed for ABS, travel computing, travel and time tracking, planning, navigation, diagnostics, or collision warning. Other heavy vehicles (i.e. buses) may contain video cameras or other recording devices. These standalone devices may also contain incident data.
As with passenger vehicle EDR analysis, heavy vehicle EDR data and analysis can be an integral part of an accident reconstruction, which may or may not include inspection of the vehicles and the site, analysis of police reports and scene photographs, and an evaluation of the witness statements/testimony.