I suppose there could be an explanation but I haven't been able to find anything similar after searching.
Last night I parked my car and 20 mins later my son told me the lights were on. Obviously I just leave it on auto so this never happens but I assumed I had knocked the stalk and went out to turn them off.
When I got into the car every light on the dash was flashing at random, as well as Abs fault, parking brake fault, lights on, alarm flashing etc,
I started the car and it's fine. Lots of power in the battery. Turned it off again and all hell broke loose once again on the dash.
I have removed the earth lead from the battery, and have no idea where to go with this one.

Is it possibly a problem with the ignition turning itself on and off (bad connection) or is it time to call in a priest?

 

I'd start with the light stalk / its wiring. It gets lots of use and they're known for occasional faults though this sounds extreme.

Also check there's no signs of damp or water in the boot - remove spare to check.

If you've any aftermarket electrics, or wiring someone may have modified, suspect them.

 

+1 on water in the spare tire well.

Have you tried reconnecting the battery again? I'm wondering if this was a one-time event or if it will repeat itself.

 

I have tried the battery and it's doing exactly the same thing.

Next job is to look at the ignition and steering column. I am not sure how these are disassembled, but I guess it be self explanatory when I start.

Thanks for the suggestions lads.

 

I had the same problem on the same model (nightmare). This went on for a few years and included not able to start, not able to move the car because of park brake fault and several engine cut outs at high speed. After several visits to main dealers it was eventually solved by Stratstone Jaguar in Stoke on Trent and explained as a damaged wire in the loom as it passed through the bulkhead. Sorted with insulation tape.