This paper briefly discusses the development of the diesel engine ECM from the late 1980's to the present with emphasis on the data recording capabilities related to vehicle accident reconstruction. In particular, vehicle diagnostic sensors which continuously monitor engine speed, vehicle speed, brake switch condition (on/off), clutch position (on/off), cruise switch condition (on/off), etc are discussed, as well as software capabilities which track rapid deceleration event ("quick stop occurrences") and provide a "snapshot" of the vehicle's properties during the moments just prior to and after a collision. Recommendations on how one might interrogate an ECM and preserve post-crash data are presented. Several case studies highlighting the use of data obtained from a truck's ECM after a crash are discussed. (A)
Abstract