I purchased my 2012 Jaguar XF Portfolio in 2017 with 80,000 miles on it. It has given me minor problems but never any having do with the engine or drivetrain -- knock on wood.

But some time ago the headlights stopped working properly. Around that time the Blocked High Beam Sensor warning would come on even though nothing appeared to be blocking the sensor located in the body of the rear view mirror. The warning would come on for a few minutes and then disappear for no apparent reason.

At first one light would suddenly switch off while driving at night, and then the other light, but never the two at the same time. In the beginning, it didn't happen often so I didn't do anything about it. If I shut off the car and restarted it the problem fixed itself, until the next time, anyway.

Over time, though, the problem got worse. Now if I drive it at night, one light will turn off and then the other will turn off, leaving me driving in darkness. If I turn off the car and restart it, the problem recurs over and over and over again. A few minutes of light followed by sudden, total darkness.

I took my car to the dealership that sold it to me. They said the camera/sensor/whatever it is in the rear view mirror was toast and they replaced it. When I drove the car at night, the problem resurfaced same as before. I insisted they take the car back and fix the problem properly. They said the two-part plastic cover surrounding the rear view mirror was blocking the sensor so they removed it and everything now was fine. (This makes no sense to me. They're saying the part is badly designed?) They also said they simulated nighttime driving by covering the sensor and the problem did not repeat itself. Of course, the next time I drove it at night the problem was still there, as if they had done nothing at all in an attempt to fix it.

Does anyone here have any idea what the real problem may be?

 

Stupid question, did they check the bulbs? To me this sounds like your xenons are on the way out (if you have xenon light that is)
A bad xenon bulb typically starts fine but turns off after a couple minutes.

Chris

 

It's a fair question. I'm pretty sure they checked and the bulbs are not the problem. And the bulbs are HID as far as I know. Also, if the bulbs were the problem, I don't think the left one and the right one would go out alternately, and then later both would go out at the same time and then come back on after restarting the car. So could it be that when the lights are set to Auto, the car "thinks" it's daytime? I'm no engineer, but I suspect the problem is whatever is controlling the headlights/determining that it's dark out. A sensor? I don't know enough about this car to know what's causing the problem. Bad wiring? Bad stalk? Computer malfunction? Failure of the motor inside the headlight assembly?

 

I'd have check the bulbs and ballasts again if I where you. Bad HID / Xenons do exactly what you describe. They work for a couple minutes and then turn off, and they will come on again as soon as you restart the car. You might see them flickering and / or turn red when standing in front of the car.
If there was an issue with the electronics or daylight sensor both lights would would likely go off at the same time, not only on one side as you described.

You can easily check for a bad day light sensor by turning the headlights from Auto to constant on. If the lights still turn off its not a sensor issue.

Chris

 

That still doesn't explain the false Blocked High Beam Sensor warning which persists even after the sensor/camera thingy in the rear view mirror was replaced, though maybe there is more than one problem here that needs to be dealt with.

Your suggestion is a good one. Thanks.

 

Stick to basics here otherwise you will spend thousands chasing your own tail. Change the bulbs. Or convert to LED. They use D1S xenon bulbs and these are easy to get anywhere.

 

Why would you assume that? They didn't fix it did they? After 2 tries I would assume they are stabbing at the issue replacing parts....and making excuses for not properly diagnosing...