The 87 harness will control the electric fan, but there is no electric fan on an 85 car. If you are attempting to put an 87 harness on an 85 engine, it won't fit because of the layout. You would need an 87 engine layout to use the 87 harness-only.
No SES codes are set with or without the powermaster system in place.
The RIV has an odd connector used for "leveling" system that was never actually in the ECM code, but the wires were in place on the harness and didn't connect to anything. Also, the analog dash RIV had an unused connector, like the Regal, for a digital dash turbo boost light. Conversely, if the was fitted with the digital dash, the MAP connector was unused and not connected to anything.
-John