Gentlemen,

I have an issue with my light sensor device.
If I chose sensor light functionality on the multi-function switch and turn on the engine, light turns on as expected but it switches off again after 30 seconds.
The dealer already checked the sensor device at the rear mirror but this was ok. Today I changed the multi-function headlight switch by a brand new one but it still does not work.

Does anybody has an idea?
Thanks for your feedback!

 

Umm, couple questions.

It may seem obvious, but you'd be surprised here. I assume your car is pre 2003 since it is a 4.0. Also, you mention the sensor being on the mirror. Is there what looks like a small plastic dome on your dash? If so, that is actually the sensor for the headlamps.
Also, are you doing the test at night? From the sound of it, if the headlamps are turning off after 30 seconds, the timer is working. There are three settings on the switch. The first selection is no delay, the second is 30 seconds, and the last is 2 minutes. Try the different settings and see if there is a difference.

 

The dome in the dash is the light sensor, have you tried covering it up with something to test?

 

You are right, there is a dome in the dashboard. And, now as you menstion, there is something suspicious with it. Exactly since the sensor light stopped working, the LED in the dome is permanently on.
I do all my test in my dark garage and I checked all switch settings. There is no difference in the behaviour. As far as I know the different settings are only related to the time the light stays on after turning off the engine.

The diagnostic device does not show any error. Nothing else seems to be impacted, locking works, alarm system is ok. By locking the car the LED which is permanently on starts blinking more bright.
Do you have an idea?

 

Sounds to me that it is either an issue with the module that controls the delay or the sensor itself. I would replace the sensor on the dash first.

 

steinmetz - you say "The diagnostic device does not show any error", but if you mean an ordinary OBD device then it wouldn't, because the kind of light you mean (as far as I can tell) would not affect engine emissions etc.

It may well be diagnosable/testable using a dealer-type device. (Probably not worth the cost, especially at this stage.)

 

The jaguar dealer did the diagnostics, I am not sure which device was used. I guess the repacement of the sensor is quite an exercise because the entire dashboard needs to be removed.
Do you know where the control unit is located?

Thank you very much for all your feedback!

 

I've not figured out which device you mean

The strip at the top of the dash by the windscreen can be removed separately, if that would help.

If you plan to do any of this yourself beware of airbags!

If a dealer knows how to use IDS/WDS (etc) they can do a LOT, but it takes real knowledge and time so maybe they were short of one or both.

However, the fault may be nothing to do with the device you mention but instead may be something else - and before taking dashboard etc apart I'd hunt around to see if this idea leads anywhere useful.

 

That sounds like I should not try it by myself.
The jaguar dealer spent once 4h on this and didn't succeed and I am not very much experienced with electronics.
I will try to replace all dependent relays and see how far I come.

I will keep you updated.
Thanks again for your support!

 

what is the exact name of the dome sensor on the dash...what is the dome called...mine is gone and i want to get a new one