Description and diagnosis of this module

The output stages of both valvetronic actuators are supplied by a relay, which is switched to the ECU. The voltage in the ECU is needed for the correction of the issued duty factor of the output stage, which is dependant to the battery voltage.

The supply voltage for the output stages is monitored permanently by the ECU and if the supply voltage gets out of the permitted range (5.7-17V), then this malfunction will be detected and the DTC will be stored.

Additional to the storage of this fault code the valvetronic actuators are driven to their end positions. A further diagnosis will be carried out - see VALVETRONIC LIMP-HOME .

See the summary table for further details.

Power Supply Over Voltage - P1055 / P1058

Power Supply Under Voltage - P1056 / P1059

Rationality Check - P1057 / P1060