Woops, originally posted in wrong forum:
Some months ago, the rain-sensing wipers on my 2004 XJR stopped 'sensing'. The auto setting on the wiper stalk basically put the wipers into the fastest (manual) delay wipe mode. The rain sensing wipers sure were convenient, but I figured the much cheaper answer was for me to simply turn them on and off like the old days rather than going to the local dealer for a diagnostic. About the same time, I began to notice that the lights occasionally began to flicker. Initially I only noticed it at dusk/dawn and I figured that the system just couldn't figure out whether they should be on or off. It's now done it a couple of times in both very dark and very light (only noticed because the touch-screen display in the dash was flickering between day and night mode) conditions.
Any chance that both auto functions are controlled by a single controller unit that may be going out?

 

nope they are totally different sensors =)

 

When I first got my car, I had problems with the lights flickering from on to off at dusk, seemingly when I went under street lights. The problem went away by itself, so I don't know what was happening.

 

It was telling you to fill the tank up xD

 

I get the flicker too - very annoying! By the way, if the nav screen changes brightness its due to the light sensor, not rain. The rain brings on the headlights but doesnt change the nav brightness or change illumination of clock/dash, etc...

My flicker is intermittent. When it happens its nearly always at dusk/dawn, but sometimes it behaves very well. After a battery disconnect and reconnect it went away for a few weeks then came back again.

May or may not be connected, but I also get the occasionaly headlamp (non-xenon)subtle flicker of headlights (not nav screen) in proper darkness with no rain.

The mystery continues!

 

Yeah, I knew that the rain and light sensors were different. It probably wasn't clear in my original post, but I was really asking of both sensors were processed through a common controller (circuit board) that may be failing. My nav screen flicker seems to be associated with the lights (which makes sense since the screen goes to 'night' mode when the head lights come on). The last time it happened was today at lunch. 11:30 am, bright cloudless skies. When I noticed it I moved the light switch from "auto" to "off" and it immediately stopped.
Guess I'm going to have to go to the dealer, but it hurts my wallet to think about it.

 

Hi did you find out what the problem was with the flicker of the dawn/dusk
I have the same issue and also the head lights do it on there own once and a while
Thank YOu