So a couple of weeks ago I turned on my headlights and the offside one immediately went out and I got the 3 amigos on the dashboard - ABS, brake & DSC lights as well as the ‘hill descent control inactive’ and ‘air suspension inactive’ errors.
Turned out the xenon bulb blew spectacularly and shattered glass everywhere. Headlamp cleaned out and new bulb fitted but now I get the same issue around 1-2 mins after turning on the headlights - 3 lights and the errors.
I’ve changed the xenon module, tried disconnecting the battery and there are no codes stored. The weird thing is that you can get rid of the errors by switching off the car, turning it back on and doing the old ‘lock to lock’ move in the same way as after the battery is disconnected.
Battery is pretty new and the other odd thing is that my IID diagnostic tool can’t read any live values anymore and the software seems to think the ignition is off all the time.

Any ideas where to look next? Fuse 5 & 15 (diagnostic related) are fine. 2005 Range Rover L322 TD6
2009 Jaguar XK 5.0 Portfolio
1969 Jaguar E Type Series 2, 2 Plus 2

Ignition switch dying? Check the voltages on the fuses, see if a bunch of them are lower than the others. The IGN/AUX output of my switch played up so those circuits were only getting around 10V, which was giving a suspension fault error.

Interesting thought, I’ll check over the weekend. 2005 Range Rover L322 TD6
2009 Jaguar XK 5.0 Portfolio
1969 Jaguar E Type Series 2, 2 Plus 2