I recently purchased a 2018 XF Sportbrake. I am not new to late(r) model Jaguars, but this is my first XF. I am not sure what are "normal quirks" and what may require attention, coming to the forum for some help. When I unlock the car there is a humming noise which begins emanating from under the hood. As best I can tell it is the right-front of the car. (passenger front, LHD). After the car has been driven and parked, when I exit the vehicle I can hear the noise again. The car will continue to make this noise indefinitely, although I imagine eventually it must time out. If I lock the car, it will silence the noise, but it is not instantaneous. Just curious what this noise could be, and if its normal for the XF, or it is indicative of a pending failure/problem. Many thanks.

 

I hear the same noise. Did you ever find out what the cause was?

 

One possible source is the LED headlights as they have a built in cooling fans since they run so darn hot. This fan can and does run after the car is shut off too.
But this is just a guess.
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