Update: Had the ECU checked by BBA-Reman, no faults found and unit returned. Fitted a new Haldex pump (I noticed the earth strap on the old pump had broken), but still no comms.

Visually checked fuse s22 - OK.

I checked there is power at the plug. My pin 2 was not brown, it was orange/black. Pin 7 was brown, a check across pins 1 and 7 shows 12.4V. Across pins 1 and 2 shows approx 10v.

I'm a bit lost at the moment - Any advice?