Electronic Logging Device (ELD)

A federally mandated device that automatically records a driver's driving time and duty status to ensure HOS compliance.

An Electronic Logging Device (ELD) is a piece of hardware that connects to a commercial vehicle's engine control module to automatically record driving time, engine hours, vehicle movement, miles driven, and location information. The ELD mandate, which took full effect in December 2017, requires most CMV drivers who maintain records of duty status (RODS) to use an ELD to log their Hours of Service. This technology replaces the traditional paper logbook, aiming to increase compliance with HOS rules and thereby reduce fatigue-related crashes. The device automatically switches to 'Driving' status when the vehicle is in motion and provides a standardized data format for law enforcement to review during roadside inspections. Carriers must ensure their ELDs are chosen from the FMCSA's list of registered and self-certified devices to be compliant.

Example

During a roadside inspection, an officer requests the driver's logs. The driver presents their ELD display, which shows a flagged violation from the previous day where they drove for 11 hours and 15 minutes, exceeding the 11-hour limit.