Bought a second hand F Type, does anyone knows what the device next to the rearview mirror could be?

 

Well, that’s the spot a toll transponder or other RF device would go, it’s an area without the IR-blocking coating, which also blocks RF (including radar detectors.)

So probably a toll or parking transponder. Mine attaches with Velcro.

 

My 2018 has one of those too. I bought it new, so it came from the factory whatever it is.

 

Now that you mention it, the area intended for RF devices has the black circles, but it isn’t solid black.

Edit: what a dope, my car has it too. My toll transponder is under it. Could be the sensor for the rain-sensing wipers. It’s visible in the shop manual, but I didn’t see it identified.

 

As per the thread below it is the humidity sensor.

https://www.jaguarforums.com/forum/f...mirror-243880/