Prints will tell you where the RSL lands in the controller. Terminator is typically in the hoistway gutter in the pit or bottom hall button box, each RSL (Car, Hall, Group)has its own. I would agree that continuity between your 30VDC and datalink is not good. Would recommend disconnecting the group link in the MR and wire in a RS board up there and see if that clears the issue. If not your be looking at a new RCB2 board if they are still available.
