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Sorry for the newb question but what is this and where does it go to or come from?

Thanks!

 

That is the cable connection for the battery tender which kept your car's original factory battery charged on board the transport ship during its Atlantic crossing from the UK to the USA. It served its purpose long ago so you can tuck that connection out of the way and forget about it....

 

Wow. Thank you so much, Jon89! Now I can sleep. =)

 

It's installed by Jaguar as their entry in the highest post competition where it's in second place below the "best oil" question.

The lead is the harness connection for the Transit Relay which is removed and discarded during PDI.





The connector is then tucked away behind the trim waiting to be discovered by a new owner months or years later.

Graham