What is the Importance of a Semi-Truck Black Box?


Our lives and our nation’s economy depend greatly on the goods and services brought to communities by large commercial trucks. Unfortunately, the downside to this necessity is roadways congested with massive, unwieldy trucks outweighing standard passenger vehicles by as much as 14,000 pounds. In an accident involving an 18-wheeler and an average car, the motorists inside the smaller vehicle face a tremendous risk of serious injury or death.

Often, truck drivers or negligent trucking companies are at fault for truck accidents due to driver error, fatigue, distraction, poor training, or inadequate driving-hour monitoring. However, large trucking companies also have powerful attorneys and insurance companies that may dispute their liability for a truck accident. 

One of the most important tools for truck accident injury victims is the black box installed in most semi-tractor-trailer trucks. What is the commercial trucker’s black box, and how does it provide critical evidence in a truck accident claim?

What Is a Black Box in a Semi-Truck?

We’ve all heard officials speak of locating the “black box” after a devastating plane crash, but many people remain unaware that most commercial trucks now also contain black box devices. Also known as an event-data recorder, a black box is an electronic system control module programmed to store information. In commercial trucks, the black box records an array of critical data that an investigator can retrieve after a crash. Data stored in a truck’s black box includes the following:

  • The number of driving hours accumulated on the trip before the crash
  • How far the truck has traveled since the last break
  • The speed of the truck just prior to the crash
  • Whether or not the truck driver applied the brakes, how many seconds before the crash they applied the brakes, and how well the brakes functioned during the crash
  • The status of other important systems on the truck such as steering, cruise control, transmission function, and other insights into vehicle function
  • Whether there was a sudden deceleration in speed before the crash
  • The electronic logging of the driver’s driving hours, off-duty hours, and number of driving breaks
  • The exact coordinates of the accident

Many black boxes also log the status inside the truck’s cab at the time of the crash, such as airbag deployment and whether or not the driver was wearing a seatbelt. Some black box models record information continually and store it for several days, while others may trigger at the moment of the crash and then log all pertinent information from the moments leading up to the crash.

How Does a Semi-Truck’s Black Box Help After a Crash?

Texas and the majority of other states have fault-based insurance systems that require injury victims in truck accidents to prove fault before they can make a successful claim for damages like property damage, medical expenses, and lost wages against a truck driver or trucking company after an accident. The truck’s black box contains critical data about the crash and the moments leading up to the crash that offer invaluable insight into how the accident occurred and the history of the truck and driver prior to the crash. If a driver failed to stop at a stop sign, was speeding before the crash, or drove erratically in the moments before the crash indicating drowsiness or distraction, this information is all stored in the black box.

Unfortunately, trucking companies commonly resist granting access to black box information after a crash because they seek to avoid liability. In some cases, they may even erase or alter the information. An experienced attorney can immediately require a trucking company to preserve the black box information and produce it for examination. This is one reason it’s highly beneficial to hire an experienced truck accident lawyer in Austin after an accident involving a large commercial truck.