This is my OM 642 Mercedes sprinter van when I bought it the brake lines have been replaced and I needed to bleed the brake lines out but traditional bleeding would not work for me so I had to undo the fuse on the ABS so what you do is your turn the key on remove the fuse so that Ecm knows and it closes the circuit  turn the key off and just do a normal procedure like he would any other vehicle works excellent now hope the video is helpful

ESP light on
ABS LIGHT ON
BRAKE LIGHT ON
Service brake system