They will not turn on while the headlights are on but when the headlights are off they come one. Yes I have checked the dimmer knob behind the steering wheel.

It all started while troubleshooting why I could not turn off the ASC. I took out the center console units and inspected the solder points on the board with the ASC button. Everything looked fine. Still could not get the ASC to turn off. I put everything back together and went for a drive. Everything worked fine..... until I turned on the headlights and off went the lights on all the gauges and center console lights. Thought maybe I blew a fuse but when I turned the headlights off they all came back.

Any ideas?

 

Here are some suggestions:
https://www.jaguarforums.com/forum/x...76/#post643308

https://www.jaguarforums.com/forum/x...24/#post614599

It may also be the Dimmer Knob on the Column. When it gets cold, sometimes the grease inside those and other switches gets hard and does not allow the contacts to connect properly. Try heating up the vehicle, quickly turn the knob back and forth a few times, and see if it starts working. Also try that with your Headlight switch because they too can do this.