Cummins® Service Engine Model Product Identification C8.3 Industrial Page E-16 Section E - Engine System Identification The control system is identified with the letters "CM" followed by the control system model number. The technology identifier after the control system designates the prevailing technology used with the engine. (See table in this procedure for letter designations.) Example: 1 On-Highway automotive "X" 15 liter engine 2 Control system number 871 3 Technology supported; Electric EGR and Diesel Particulate Filter