The unit is a system made up of the engine and all circuits required for its operation:
fuel feed circuit
air turbocharging system
exhaust system with catalytic converter
oil vapour recirculation system
exhaust gas recirculation (E.G.R.) system
engine cooling system.
The operation of these systems is optimised by an electronic control system governed by a control unit.An awareness of control unit operating strategies allows an overview of the entire system UNIT 10