How are you getting on with this? From the OBD port the can wires go direct to the gateway, vcds talks to the gateway, the gate way allows can traffic to flow, if you get no comms with engine ecu check gateway DTCs and MVBs. On dash what does your esp do/not do? If the light on the button never lights up it’s more likely your esp is never on. Can you get comms with the ABS and Transmition? They are on same can as engine ecu. Oil pressure on some models is direct to cluster... check earths, trapped wires, plugs etc etc. If it worked before it should again!