Trac not Available message

Jaguar X308.

As reported on another thread, I had problems with gearbox fault, engine safe mode, trac not available, asc not available. The throttle position sensor was changed which seemed to improve matters for a couple of days and then on a round trip of around 40-50 miles the fault returned and wouldn't clear until the engine cooled down. Had the whole throttle body changed and the fault hasn't returned in over 100 miles.

HOWEVER! I wonder if anyone has had this fault I have experienced? Earlier in the year I was travelling on a motorway around 55-60 mph middle lane when a lorry indicated to pull out. I took my foot off the gas pedal and flashed my lights. I immediately got a "Trac not Available" message, the orange tyre warning light and other amber warning light lit and the radio went off. Within a couple of seconds, everything went back to normal. Tried it again later same thing happened. Then all was fine. Lift off, flash lights - no reaction. Until today. Travelling at 50 MPH off gas and flashed lights and "Trac not Available" lit radio went off. A couple of seconds later everything back to normal.

I will get the codes read to see if it points to anything but is this a one off or has anyone else experienced this event?