Still new to these new fangled gizmo's but take your point 180. Also apologies for the extended time in sorting problems with car but I have other things that take priority. However, pleased to report normal service has been resumed with my XF with no more Christmas tree decorations to cause a distraction. Main culprits were as mentioned before a cracked ABS ring on a front hub. Took the easy way out on that one and replaced the hub with a good used version. Also replaced all four wheel speed sensors and after carrying out a re-solder job on the RCU decided there were other issues with that unit. Close inspection revealed a slightly burned relay contact. As this was the original RCU according to the date printed on it's side I decided to replace with a new unit bought from ROCK Auto NY and sent to my in-laws address in CA. She who must be obayed has just returned home after a visit so brought the item back with her, fitted it this afternoon and all is restored and back to normal. Also carried out a parasitic drain on battery check as per Eric the car guys thread to find that power is being drained through the radio and interior light switch. Suggestions on a good radio replacement would be appreciated.