Now for the next problem. I drove my XK in the semi-dark for the first time yesterday and could not see the instruments very well or even at all once it became dark. Headlights and sidelights were on of course.The rotary rheostat on the auxiliary lighting panel didn't do anything. I had a bit of a look around today without removing the auxiliary panel but couldn't see anything amiss. I don't really know where to start with diagnosis of this fault and would be grateful for any pointers. I have a downloaded copy of the workshop manual but it is not much help.

 

If your headlight switch is set to AUTO, turn it to the OFF position and see if you can adjust the dash brightness.

​​​​​Give @Cee Jay credit for this one.
https://www.jaguarforums.com/forum/x...solved-241909/

 

 

Thanks to you both about this. I tried it out this morning when it was still dark and lo & behold the "rheostat" worked. However even max was a little dim for my liking but I may get used to it along with the dim headlights which will probably be one of the next few jobs. These little quirks are logical once you know about them but it takes longer to grasp them when you get old! Anyway the matter is now RESOLVED.