Event Data Recorder

An event data recorder stores a short segment of vehicle data triggered by a crash or near-crash event. Recorded parameters commonly include pre-crash vehicle speed, engine throttle, brake application, delta-V during impact, and seat belt status.

In commercial vehicles the recording function is often integrated with the engine control module rather than housed in a separate unit as in passenger cars.

Alternative Names:

EDR, Crash Data Recorder

Why it Matters?

EDR output is the closest thing to an objective witness in a crash case, and it routinely resolves speed and braking disputes that experts would otherwise argue at length. It also constrains reconstruction: a reconstruction opinion inconsistent with recorded data is vulnerable on cross-examination and at the Daubert stage.

Frequently Confused with

Related terms

Frequently asked questions

Is an EDR the same as a black box?

Black box is the colloquial term, and in commercial trucks it usually refers to the engine control module and any integrated event recording function rather than a separate dedicated device.

Do I need permission to download EDR data?

Generally yes. Several states require the vehicle owner's consent or a court order, and downloading an adverse party's vehicle without agreement or an order invites both evidentiary and sanctions problems.