ABS light, ASC and TRAC unavailable messages on 2000 Jaguar XJ8

Similar to "Anonymous, Fort Washington, MD, May 24, 2010, 14:10". I have intermitent ABS warning light, ASC and TRAC warning messages - all 3 come on together. Usually OK when I start up, they come on when I hit a bump. Gradually getting worse - i.e. smaller and smaller bumps. Fully expect this to become permanent soon. The bumping aspect points to some kind of loose wire or plug, all three coming on at the same time points to some kind of common item. Maybe a loose cable harness plug or a corroded connection somewhere - any ideas?

Asked by for the 2000 Jaguar XJ8
As expected problem became permanent for around 6 months - although car seems to handle exactly as before. Then started becoming intermittent again. Problem messages for a few days, the OK for a few days. Handling, stopping seem unaffected. Adrian
Same problem, "Track not available" "No ABS" Not sure what it means. Just went over 126,000 miles. without a problem.Does anybody know what Code this would be??
2 more answers , 1 more comment
I don't have an answer looking for one. I have this exact same problem, 2000 xj8. OMG!!!
Can anyone help? PO171, PO340, ASC, No TRAC, ABS... Is this some kind of Jaguar hustle?!!
mine just came up a day after a flat L rear tyre. I was parked and only drove a couple feet before I realized it was flat. Changed to the spare and all was good until just now. abs,trac,asc all related obviously, just want to know if anyone had any probs driving in this condition?
you have to replace (rebuilt) the ABS Module. Cost $60 look for ABS rebuild modules