Mike, I don't know of any way to make the OBD code show up on the dash. But, take the vehicle to a local auto parts store and most of them will let you borrow a code reader to take out to your car in the parking lot and get the codes at that point. From there, you can look on http://www.obd-codes.com/trouble_codes/jaguar/ for the Jaguar specific codes (all start with P1XXX) or http://www.obd-codes.com/trouble_codes/ for the generic codes (all start with P0XXX) to get a more descriptive explanation of what the code is. From there, post what code(s) you got and we can go from there.

The common problems is a lean condition on banks 1 and 2, which is normally caused by some o-rings on the intake (P0171 and P0174). Another common one as of late is a misfire code (P030X where X is the cylinder that is misfiring). Unfortunately, to tell you what is wrong is not possible at this point. Get the code(s) and then we can assist you a lot better.