Kim has reported that the dash has had this message all day today, I think this is supposed to appear when it gets dark.

So perhaps the light sensor has failed or is dirty. Can someone say where it can be found?

Thanks

 

When you have the Auto headlight feature fitted, this warning is normally displayed if the rotary collar is NOT in the auto position and the sensor detects the ambient light level has dropped to the point where the lights would have come on automatically.

Certainly sounds like an issue with the light sensor which is mounted in the back of the rearview mirror facing the windscreen.

Graham

 

Have you tried rotating the sensor on the back of the mirror several times? This adjusts the ambient light reading. This should clean the contacts. I did not get an error message but it did stop the lights from coming on and off at strange times. Jim

 

I had this problem recently. It was the stalk on the steering column. I had to get dealer to replace it, ouch !

 

I have been getting the same message on my 2004. My auto headlamp function doesn't work right now. Haven't yet investigated, but will keep all your suggestions in mind when I do!

 

I stripped down unit behind the rear view mirror to get to the light sensor, tweaked the connectors and wiring, no joy.

 

See my post above.

 

I don't understand this, have a look at page 87 here http://www.captainjaguarscathouse.co...ec%20Guide.pdf

May be different for your car, but you can see that the lights off signal comes from rear view mirror module, regardless of the position of the light stalk. So the only thing that could cause the problem is the mirror, I don't understand why the dealer would change the stalk.

After finding this I realise that I was looking at the rain sensor not the light sensor so will have another tweak tonight and test out the sctual signal from the mirror to the body module.

 

Well stalk changed and £250 later all is well. Must be the wire from the auto position on the stalk.

 

Can you elaborate on this a bit, how do you get to the sensor to rotate it?

 

I think you'll have the later rear view mirror without any rotary adjustment switch for the ambient light sensor sensor.

Graham

 

If you need to get at the stalk wiring (which does frequently break) download JTIS from the HOW-TO sticky at the top of this section (if you haven't already) and look at these sections
86.65.92 Steering Column Multifunction Switch in Chassis, where you'll also find Steering Wheel Removal
In Body and Paint, 501-20B you'll find the driver air bag removal details.
Be careful to follow the airbag instructions - they can seriously injure you.

 

Got back on to this one today.

There are 5 connections to the rear view mirror, Power, Ground, Reverse input, Mirror tint output, Auto Light output.

I removed the mirror and tested it on the bench unfortunately the Auto light output is non functional, so it looks like I will need to find a new/old mirror.

I first unclipped the two plastic covers at the base of the mirror, and disconnected the harness. The mirror came off the window easily by sliding/wiggling it down/parallel to the screen.

Surprisingly there are three differenet light sensors on the mirror, one pointing forwards, and one back, these are both light dependant resistors LDRs. Then there is also a photodiode that points generally upwards in the mirror mounting housing. The system is implemented using a Motorola (now Freescale) MC68HC705JJ7 8 bit microcontroller.

Some pics...

 

dang, you dissected that thing! I just cleaned the dust from the sensor.