The fuel pressure in the rail is constantly applied to the injectors. Fuel is injected into the combustion chambers by electrical activation controlled by the DDE control units.
The electrical lines to the fuel injectors as well as the coils in the fuel injectors are monitored for short-circuits and breaks. Smooth running measurement should be carried out if a mechanical defect is suspected in a fuel injector. In the case of an electrical defect, the following fault codes are stored depending on the affected fuel injector.
Important: If one of the fault codes occurs with defect types "current on High side too high" or "current on Low side too high", although the fault is allocated to a fuel injector, due to the common line (U_MVxx, for one bank each), the cause of the fault may be in any line of the two cylinders of the respective cylinder bank.
Consequences:
The engine shuts down in conjunction with the fault types "current on high side too high" and "current on low side too high". In the case of the fault type "load drop" (break in line) the engine continues to operate if not more than one injector is affected.