California Truck Accident Black Box Evidence: ECM, EDR And Electronic Data

Electronic information from a commercial truck can provide important details after a serious collision. The term “truck black box” is commonly used, but a truck may actually contain several different electronic systems that record different types of information.

DAG Law Firm, APC represents people injured in serious truck accidents throughout California. Electronic truck data may help explain speed, braking, driver hours, or other parts of a crash, but it should be reviewed with the rest of the available information. You do not pay attorney fees unless we win your case. Call (323) 930-2020 or contact DAG Law Firm today for a free consultation.

What Does A Truck Black Box Actually Mean?

“Black box” is a general term rather than the name of one standard device installed in every commercial truck.

Depending on the truck, electronic information may come from an Electronic Control Module, Event Data Recorder, electronic logging device, telematics system, onboard camera, or another vehicle system.

NHTSA defines an Event Data Recorder, or EDR, as a device or function that records technical vehicle and occupant information for a short period before, during, and after a crash. NHTSA also explains that EDRs should not be confused with video systems or devices used to record truck-driver hours.

The first step is therefore identifying which electronic systems were actually installed on the truck rather than assuming every commercial vehicle records the same information.

ECM And EDR Data Are Not Always The Same

An Electronic Control Module, or ECM, generally helps control or monitor parts of the engine or vehicle. Depending on the system, it may also store information that becomes useful after a crash.

An Event Data Recorder has a more specific crash-related purpose. NHTSA describes EDR information as technical vehicle and occupant data recorded for a brief period surrounding a collision.

There can be overlap between the information stored by these systems, but the terms should not automatically be treated as interchangeable.

The truck manufacturer, engine, model year, equipment, software, and individual electronic modules can all affect what information is available.

What Information May Be Available After A Truck Accident?

The information available depends on the specific truck and recording system.

Potential data may include vehicle speed, engine speed, throttle position, brake activity, engine load, cruise-control status, or other operating information. Some systems may preserve information only when a particular event or trigger occurs.

An EDR may also record information concerning vehicle dynamics, driver inputs, crash characteristics, and restraint systems depending on its design.

The presence of an ECM or EDR does not guarantee that every commonly discussed data point was recorded. The actual system and available download must be examined to determine what information exists.

Electronic Logging Devices Record Different Information

An electronic logging device, or ELD, serves a different purpose from an ECM or EDR.

FMCSA explains that an ELD synchronizes with a commercial vehicle’s engine and automatically records driving time to help track a driver’s hours of service.

An ECM or EDR may help answer questions about what the truck was doing around the time of the crash. An ELD may help answer questions about how long the driver had been driving or working.

Those records may sometimes be considered together, but they should not be described as the same type of evidence.

Readers can learn more about California truck driver hours-of-service rules.

Electronic Data Can Help Explain How A Crash Happened

When useful electronic information exists, it may help provide another view of what the truck was doing before or during a collision.

For example, speed information may be compared with video, vehicle damage, roadway marks, witness statements, and final vehicle positions. Brake or throttle information may provide additional context concerning vehicle operation.

Electronic information may also help establish timing or identify events that correspond with other records.

NHTSA recognizes EDR information as useful in crash investigations because it can provide technical information about vehicle behavior surrounding a collision.

Electronic data should generally be reviewed with other available information rather than treated as the only answer to why the crash occurred.

Truck Electronic Data Has Limits

Electronic truck data can be useful without being perfect.

Recorded values may be measured or calculated by the truck’s own systems. The accuracy and meaning of a particular value can depend on how that system works and what was happening to the vehicle.

Different systems can also record different amounts of information. Some may preserve only a few seconds surrounding an event, while others can contain operational, diagnostic, or trip information.

Data also requires interpretation. A recorded speed, brake input, or fault code should be considered in the context of the truck, roadway, physical evidence, and other available records.

No electronic download should automatically be treated as proving exactly how a collision occurred.

Useful Electronic Data May Not Always Be Available

A serious crash does not guarantee that useful electronic information can be recovered.

A truck may have limited recording capabilities. A collision may not trigger a particular event recorder. Older information may have been stored instead, or a module may be physically damaged.

Different vehicle systems can also store different information. One damaged component does not necessarily mean that every possible electronic source is unavailable.

When useful electronic information cannot be recovered, investigators may need to rely more heavily on photographs, video, witnesses, physical vehicle inspection, roadway information, and commercial records.

The absence of black box data does not establish how the crash occurred.

Mechanical Problems And Truck-Specific Crashes May Require More Than Electronic Data

Electronic systems can sometimes contain diagnostic information, but a fault code by itself does not necessarily prove that a mechanical failure caused a crash.

Questions involving brakes, tires, steering, coupling equipment, or another mechanical issue may require maintenance histories, inspection records, repair documents, photographs, and examination of the actual truck.

Electronic information can also be useful in truck-specific crashes. A jackknife truck accident may raise questions about speed, braking, stability, and tractor-trailer movement. An underride truck accident may require reviewing vehicle speeds, impact positions, and the movement of both vehicles.

Electronic data can provide another source of information in these crashes when useful data exists. It does not independently establish why the collision happened.

Electronic Data Should Be Compared With Other Truck Accident Evidence

A truck’s electronic data is only one part of a larger accident investigation.

Other information may include collision reports, photos, surveillance video, dashcam footage, witness statements, roadway marks, vehicle damage, electronic logs, maintenance records, inspection papers, dispatch communications, cargo records, and trucking-company information.

Different records can help answer different questions. Electronic speed information can be compared with video or physical roadway information. ELD records may help evaluate driver hours. Maintenance records may help explain the condition of the truck.

Electronic information may also become important when drivers, trucking companies, or insurance carriers disagree about how a collision happened. It does not automatically determine who is responsible.

Readers can learn more about who may be responsible after a California truck accident and California truck accident insurance claims.

Resources And How DAG Law Firm Can Help

Commercial truck accident investigations can involve several forms of electronic information. ECMs, EDRs, ELDs, cameras, telematics, and other systems can provide different information, and not every truck has the same technology or recording capabilities.

DAG Law Firm provides additional resources about California truck accident laws, what to do after a truck accident, who may be responsible after a truck accident, and truck driver hours-of-service rules.

Additional information is available about trucking company negligence claims, truck accident insurance claims, common truck accident injuries, and how truck accident cases differ from car accident cases.

A serious truck accident may require reviewing available electronic truck data together with collision reports, photographs, video, witnesses, driver records, maintenance and inspection papers, cargo information, trucking-company records, insurance information, and medical records.

You do not pay attorney fees unless we win your case. There are no upfront attorney fees for qualifying truck accident matters handled on a contingency-fee basis. Call (323) 930-2020 or contact DAG Law Firm today for a free consultation.