[/QUOTE]
DARN! I was hoping it was the answer to why my car doesn’t start. But it solves the mystery of where it belongs. Thank you

 

Transit relay for transportation to the dealer. Then it's removed permanently and that small plug is all that's left. Your dealer neglected to properly stow it away like gt40 showed.
.
.
.

 

As you know which is the relay for the starter solenoid, if you pull that out it probably has a diagram on the side ( and usually the pins for the points are larger ). You could check the voltage at each of those large pins ( the ones for the points not the coil pins ), one of them should have 12v at least with the ignition on. If 12v is present, then you could come up with something to link those two large pins for the points together briefly to see if it cranks ( remember whatever you use needs to be able to carry the rated current of that relay - perhaps a suitable piece of wire with a non latching switch in the middle and connectors that will push in where the relay would go on the ends so you don't burn the fusebox or your fingers )

Also you could check the voltage at the fusebox in the right side of the trunk ( above the small battery ) at the point circled in the picture in the following post https://www.jaginfo.org/posts/2942964/

 

So contrary to the original thread, I am not hearing a click of the solenoid. I hear the fuel pump and then: nothing. I’m beginning to wonder now if it’s an issue with the anti-theft software. The key is still recognized and there are no warning lights on. I have a friend with some knowledge of jaguars who may be able to help. It’s in his garage now and will update later if he can figure out what’s wrong.

 

I finally broke down and had the car towed to a Jaguar mechanic. He told me the computer system was corrupted when I tried to charge or jump start the car. He cleared 6 communication error codes. And replaced a grounding cable from the engine to the frame. It is starting and working again. None of the codes were the type that would cause a check engine light to come on so I could never have fixed it without the software that he used.