It could signify a serious problem,ie,low oil pressure or it could be just a faulty oil pressure switch/sensor,not sure on Mercedes there could also be a low oil level sensor too,if the oil and filter haven`t been done for a while then it may be worth renewing both for peace of mind. Also I am not sure if getting it onto a relevant computer for a look at live data will show up what your actual oil pressure is reading when your light is on but often that is the way to go on modern motors and if all is well there then a faulty sensor may be your fault,good luck.
cdc, May 2014
