Do a search on OVP or oveload protection relay or overvolt protection relay.
This may be the answer.
Where is David C Class to chime in with his opinioon on OVP.
'92 300CE - Sold
2004 C240 - C7 Wheels
2015 ML350 - P1, Pano, Ash poplar wood, Sport Dinamica interior, Running Boards Keyless go.