316i 99" OBC not working after M52 swap
 

Hi everyone,
after swapping M52B25 (from a 1998 323ti) into my compact which had M43TUB19 from 1999" the OBC is not working properly. Consumption is constantly at 0.0 L/100km. I am assuming that the car loom is not the same in both cars. Is there a way to rewire the OBC (to connect it somewhere) to make it show average consumption?

Also my RPM and temp. gauge is not working but I have figured that out, just need to run 3 wires from X20 connector into cluster connectors (X16 and X17).

Thanks in advance!