Does the sender earth through the screws from its cover plate or is there a separate earth connection? I have got a 2013 wiring diagram, albeit only A4 size so you need a magnifying glass. The sender appears from the parts book (V.5.2 - Fuel System Right - P.26) to be integral with the pump - part ref #6 unless it is what they describe as the "fuel tank dip pipe" - part reference #10 and this page shows the wiring (P.69 top right corner).
Wilson
