Computers and Control Systems: Description and Operation

Other Functions Of The DME Control Unit

VarioCam Plus Control on V8 DFI Engines

VarioCam Plus technology is used for the first time in V8 engines in the Cayenne model range. This system, which may be familiar to you from the current sports car generation, enables intake valve lift switching in addition to intake camshaft adjustment. This ensures optimum running quality, low fuel consumption and low emissions as well as high power and torque ratings in conjunction with the intake system.

Variable Oil Pump on V8 Engines

The DME control unit is responsible for the demand controlled operation of the variable oil pump, while adjustment is performed hydraulically. Engine management uses the input values for engine speed, temperature and torque. Based on this information, the engaged gear wheel width and therefore the geometric displacement volume of the gear wheel set is changed through the axial movement of a gear wheel (moved hydraulically) and this in turn changes the oil pressure. The pump ensures that only the pumping action required for the relevant load range of the engine is initiated. This reduces the energy consumption of the oil pump to a minimum and also ensures demand controlled lubrication.

Control of Electric Radiator Fans

The DME control unit also activates the two drivers for the electric radiator fans in order to achieve infinitely adjustable control.