Almostallnewautomobilesproducedtodayarerequired,bylaw,toprovideaninterfacefromwhichtestequipmentcanobtaindiagnosticinformation.Thedatatransferontheseinterfacesfollowseveralstandards,noneofwhicharedirectlycompatiblewithPCsorPDAs.TheELM327isdesignedtoactasabridgebetweentheseOn-Board