The following components belong to the common rail system and influence the rail pressure control:
The rail pressure is monitored during engine start and engine operation by way of setpoint/actual value comparison. The rail pressure sensor supplies the actual value to the DDE. The setpoint is calculated by the DDE depending on the operating status. Fault codes 1190 and 1191 ”rail pressure control” are stored if the DDE determines an impermissible deviation in the rail pressure from the setpoint.
An impermissible deviation of the rail pressure from the setpoint can be caused by the following:
As from DDE software version 44 (phase-in as from 07/2000), the DDE warning lamp will be activated if faults 1190 and 1191 occur. In addition, fault code 1612 ”DDE warning lamp activated” will be stored. This fault code only indicates that the DDE warning lamp has been activated due to a fault in the rail pressure control system.
Engine start will not be possible or the engine shuts down if the DDE recognizes an impermissible rail pressure deviation.