Request Free Consultation

Every commercial truck on the roadway has what most people would call a “black box,” but the reality is that there are a few devices on a semi-truck that paint a complete digital picture of a truck’s health and show the events leading up to a recordable incident, such as an accident. Here, we want to review the purpose of both the electronic control module, the electronic logging device, and the event data recorder for a large commercial truck. If you have any questions about how this type of evidence, or any other evidence, will play a role in a claim against a truck company, we encourage you to contact a Phoenix truck accident lawyer as soon as possible.

what is a semi truck black box

The Electronic Control Module

The computer that operates modern truck engines is referred to as the electronic control module (ECM). This system consists of an array of sensors and computers that continuously monitor various truck systems, including the engine, vehicle performance, brake system, traction control system, transmission functioning, and more. This system will help determine whether a fault has occurred within the engine area and will eliminate various sensors and lights, including the “check engine” light.

The Electronic Logging Device 

Inside every large commercial truck on the roadway is something called an electronic logging device (ELD). These devices replaced previously handwritten paper logs that drivers used to keep track of their federally mandated hours of service. The ELD provides more accurate information related to the driver and how long they have been on the roadway each day and each week and helps ensure the enforcement of the hours of service requirements prescribed by the Federal Motor Carrier Safety Administration (FMCSA). 

The Event Data Recorder 

When most people think of a truck’s “black box,” they are actually referring to the event data recorder (EDR). The EDR will contain an array of information related to the driver and the vehicle up until the moments of a recordable event.

Some of the types of events that are typically recorded include a sudden deceleration or braking, airbag deployment, seat belt tensioner activation, and other actions related to the driver or vehicle that could indicate a crash or near crash happened. When the EDR is triggered to record, any information related to the vehicle gets preserved and recorded. Some of the types of information recorded include the speed of the vehicle at the time of the incident, whether or not there was cruise control engaged, whether the wheel was turning, brake applications, and more.

Who Helps Gather This Evidence?

After a truck accident occurs, the process of recovering compensation for a victim can be challenging. Any person who has been injured by the negligent actions of a truck driver or a trucking company should reach out to a skilled Phoenix personal injury lawyer as soon as possible. The trucking company is not going to be forthcoming to most individuals with handing over any of the data devices mentioned in this article. Usually, an attorney will need to work through the court system to obtain this evidence during the course of their investigation and moving toward a personal injury trial.