3.0 litre 2006 X type
Just removed the dash gauges to route a cable for a dash cam.
Removed both battery cables and connected them together while they were off . Removed the dash gauges and routed the wire where it was going to be out of the way. Being nosey I also undid the dash and had a quick look around and cleaned up the inside of any dust.
Replaced everything and now I have a no start situation, all dash lights, windows and locks operate.
Any thoughts out there? Does it need the old Jaguar dealer box connected up and something resetting or is there a procedure to go through to reset the communications?
Inertia switch???
Could that have tripped just by removing the dash cluster?
Why not check???
Will do when I can find the elusive thing 
it doesn’t appear to be in the normal spot i.e. in the footwell by the accel pedal (RHD)
The inertia switch on a LHD car is located in the footwell on the passenger side. Open the passenger door, get down and look to your Right. It will be to the right of where the passenger would put his/her feet. There is a plastic piece of trim that will look like it has a little plastic piece much like where the tow hooks are. Remove that piece of plastic and push the switch in.
Thanks James, I’ll have another look in that area tomorrow morning.
Well its not the inhibitor switch so its on a flat bed next week when I can arrange it.