GF07.16-P-3007P CDI Limiting Maximum Engine Speed, Function

GF07.16-P-3007P CDI Limiting Maximum Engine Speed, Function

The maximum engine speed limitation is used to restrict the engine speed to approx. 4500 rpm. This counteracts mechanical damage to the engine caused by overrevving. To do this the CDI control unit (N3/9) reads in the crankshaft Hall sensor (B70) and uses its signal to determine the motor speed. Above an engine speed of around 4500 rpm, the CDI control unit interrupts actuation of the fuel injectors (Y76) and reduces the fuel pressure in the rail via the quantity control valve (Y94) and the pressure control valve (Y74).

If the engine speed falls back down to under around 4500 rpm, then the CDI control unit reactuates the fuel injectors and increases the fuel pressure in the rail via the quantity control valve and the pressure control valve.