that lighter socket underneath the driver's cupholders does not give any power but the other lighter located behind the armrest(above the rear AC vent) for the rear passengers do work. I tried replacing the fuse in the trunk(Luggage Compartment Fuse box #5 according to paper manual), it did not fix it or change anything. Any other ideas or try a second new fuse? My goal is to use this to charge my phone and USB FM device. I've attached the paper manual that came with the car ; 2003 X308 XJR

 

There's probably been pop spilled in it over time. Might be rusted or gummy so it's not making connection with whatever you're trying to plug into it. Use a small screwdriver to scrape the bottom to shine it up. I think that lighter socket is hot all the time, so you need to disconnect the battery, if I remember correctly. Or remove the fuse so your screwdriver doesn't blow the fuse while you're doing this.

 

Alternatively, use a multimeter to test it: one probe to side and the other to scrape and probe the copper base. . .

 

It’s also possible that somebody removed the center console at one point and forgot to plug in that lighter. Just a thought.

 

No luck tonight but I did get my USB FM to play music on the rear cigar lighter socket. I've sprayed the socket and lighter with some electrical contact spray can. The metal surface of both items are clean. I also replaced 2 new fuses in the truck again, nothing changed. I'll have to take the armrest apart another day but this is no longer an urgent item. Thanks everyone.