Yesterday, while going trough some spare cars, I saw this part mounted in the engine bay.
On my car, I have the bracket, but nothing fitted to it.
Is it the sounder which Jaguar moved up on later models, or is it an additional security item?

EDIT: I also noticed all three cars had the switch in the cross-beam, which detects if the bonnets is open or close.
Is that connected?

 

Yes looks to be some kind of sounder ?!

 

That is a security sender, although I've only ever seen it mounted deep in the engine bay next to the sump. But if it's an early car it may be where they first put it.

I've never heard one work though, and the one on my car is disconnected. UK cars don't chirp when you lock them anyway because of noise laws.

My car also has the sensor/switch on the cross beam for the bonnet.

 

Thanks, I guess I will cross check part numbers, and take it out if they match.

My car chirps, but only on the main battery, the small sounder battery is long gone (and the suspect of my small electricity drain).

Might perform some surgery to see if I can fix up a battery to it, I think I saw some posts about that on this forum.

 

Yep, security system alarm. Found out the hard way after fiddling with electrical wiring and a ringing ear for 10 minutes.

Tested by locking the car with window down and opening door without key.

My ‘98 XJ8 has got it in the same location in your photo, ericjansen