What is a Semi-Truck’s “Black Box”? Explained

Did you know that a semi-truck has a computerized system that records data in the event that the vehicle is ever in an accident?  It is called the semi-truck’s “black box.”

Few people are aware of it, and trucking companies don’t want you to know about it since the data could reveal a truck driver’s liability.

The truck accident attorneys at TK Injury Lawyers would like to share important need-to-know information about semi-trucks and the type of “black box” systems that each truck has.

Basics of the “Black Box”

A “black box” is a computerized device that is installed in commercial vehicles. It documents the vehicle’s driving record and records the truck’s movements.

A “black box” can be a key piece of evidence to show a truck’s location and what happened moments before a crash.

While some commercial trucks have a “black box” that records continuously, other vehicles contain a computerized system that will only record in the event of a crash.

What are the Types of “Black Box” Computerized Systems?

There are a few devices that would be considered part of the “black box” computerized systems for an 18-wheeler.

These systems are electronic control modules (ECMs), electronic logging devices (ELDs), and event data recorders (EDRs).

Electronic Control Modules

Electronic control modules (ECMs) are the main computer systems that run modern-day vehicles. The system consists of separate sensors that connect directly with the vehicle’s engine. The ECM monitors and controls fuel injection timing, which is the precise moment when the fuel is injected into the combustion chamber in the engine.

The ECM also has sensors that monitor the coolant temperature, the intake air temperature, the throttle position, and the rotations per minute (RPM) of the engine. It communicates with other computer systems that are responsible for anti-lock braking, traction control, and transmission operation.

Also, it allows your vehicle to run properly and will automatically adjust conditions in order to allow your vehicle to function. ECMs are responsible for the check engine light on a vehicle, alerting you to bring your vehicle to a mechanic for diagnostic testing.

Electronic Logging Devices

An electronic logging device, or ELD, synchronizes with the engine of a commercial motor vehicle to automatically record driving data. An ELD records when a truck’s engine is running, when a truck is moving, and how many miles the truck has traveled in a given time period.

An ELD helps commercial motor vehicle drivers comply with the hours-of-service (HOS) regulations enforced by the Federal Motor Carrier Safety Administration (FMCSA). In following HOS regulations, truck drivers are only permitted to drive a certain number of hours each day.

Commercial truck drivers must transfer their driving data to safety officials. These officials review the data and will flag any violations of the HOS regulations.

The goal of electronic logging devices is to keep fatigued drivers off the roads. Even with these measures put into place, truck accidents have yet to decline.

Event Data Recorders

Event data recorders are the “black box” devices that record a vehicle’s speed, braking, and movements prior to a crash. When most people refer to a “black box” device, they are usually speaking of event data recorders (EDRs).

EDRs usually record when there is an indication that a crash may have taken place, although some EDR systems may record at all times.

Following the Code of Federal Regulations (49 CFR § 563.7), an EDR is required to record the following data:

• Frontal airbag deployment
• If stability control was on, off, or engaged (for traction)
• Speed the vehicle was traveling prior to a crash
• Sudden braking
• If the driver was using a seatbelt
• Number of crash events

This information is key to finding out the logistics behind an accident, so much so that in 2012, the National Highway Traffic Safety Administration (NHTSA) mandated that all vehicles sold in the United States must be equipped with an EDR.

How Do You Obtain “Black Box” Data from a Crash?

The data collected by a “black box” is crucial to find out which driver may have caused a crash. As you can imagine, trucking companies will take all measures to avoid “black box” data from being released during a lawsuit.

In 2020, Texas had the most fatal commercial trucking accidents in the country, accounting for 643 deaths. With such a glaring number of deaths, trucking companies are adamant about keeping “black box” data from being submitted as evidence. With fewer facts presented at trial, a truck driver has a better chance of not being held accountable.

If you are an accident victim, how do you get your hands on this data? If you choose to take your case to court, you may be able to request the semi-truck’s “black box” data during discovery (pre-trial phase). In discovery, you request information from the opposing party to use as evidence during the trial.

The request for documents or data is known as a request for production. You may be able to request “black box” data from the truck driver’s insurance company. “Black box” data is only stored for a limited time, so you will want to act quickly.

How Does “Black Box” Data Prove Fault?

Once you have accessed the “black box” data, you may be able to discern if the truck driver was responsible for your accident.

The data will show any actions by the driver which contributed to the crash. The data would reveal if the driver was speeding, when they braked, and if there were sudden changes in acceleration or deceleration.

An experienced Truck Accident Lawyer will be able to piece together the sequence of events to determine what degree of fault the truck driver held in your accident.

A Compassionate Austin Truck Accident Lawyer

No matter what you are told, neither the truck company nor the truck driver will voluntarily admit fault up front. Let the truck accident attorneys at TK Injury Lawyers be your voice. We know that anyone who has been in a truck accident has suffered physical trauma, and we are here to ease the legal process. Contact us today to schedule your free consultation.