P0460 on your Jaguar X-type

P0460 is flagged when the computer sees a problem with the fuel tank level sensors. The most likely problem is a fuel pump assembly: here is the link to the part: SP5064M Fuel Pump Assembly.

To check and confirm that the problem doesn't lie elsewhere, you need to connect a voltmeter to the connector that goes to the fuel level assembly. With the tank empty the resistance should be 30 ohms and with the tank full the resistance should be 160 Ohms. You can estimate by the amount of fuel more or less what it should be since I gave you the limits.