I do not usually use plug in electrical devices in my cars, but got a cell phone car charger recently, so plugged it into the front cigar lighter port to charge. It did not charge. I tried the cigar lighter function, and the cigar ligter heated up in the port no problem. So I tried the rear seat power port, no luck. Ditto for the rear seat cigar lighter, though that cigar lighter heated up fine too.

So I tried the cell charger in my Cadillac and it worked fine, so not the charger. I tried another device in both cars and no go in any of the three Jag ports, but it worked in the other car.

Called the PO and asked him. He said he never could charge a cell phone in the Jag ever, and assumed the power ports in Jags did not support electrical devices other than the cigar lighter itself. This seems odd to me. The rear seat power port even has a graphic on it showing it is a power port, so how could the car not support any electrical devices by design? The fuse can not be the problem as the cigar lighters both work. Ditto power not getting to the port, since the lighters works.

Anyone have any ideas why lighter plug-in devices would not work when the cigar lighters themselves do work? Car is a 2005 VDP. According to the PO this phone chargers not working was always the case from the time the car was new, and he never mentioned it to the dealership when car was under warranty as he just concluded Jags must not support add-on devices like plug-in phone chargers.

 

Measure voltage and check polarity.

 

Possibly the lighter is metal all around, so it does not matter how it is inserted, but the phone charger only has two contacts, at 6 o'clock and 12 o'clock, so those need to be matched with the terminals inside the port (assuming tip/centre is one terminal and the sides are the other).
Try rotating the phone charger while it is inserted and see if it gets power then?