G55 Electrical Problem

Hello together, question to the professionals. Have the following problem with a G55 from 06/06. As long as the engine does not run the electrics works almost normal. Start the engine starts to flicker the driving light. If you plug the charging line of the Lima stops it. alternator has been changed SAM at the front too. Everything checked what to check! If the car is unspoiled flickering the license plate light here and there on as well the back lights. Maybe someone among you is a er This is a problem that I have had.