Fellow Jaguar owners----just cured my problem on my 2005 Jaguar S type 4.2 with 21000 miles. Vehicle would start and then shut off. Bought a scanner for jaguar (131.00) plus replaced the interia switch and fuel filter. Still not start. Batteries tested good in Remotes. Anyway thought I would replace batteries with top of the line Sony batteries. Problem solved. Vehicle did not read code from the remotes and went to thief mode and shut engine off. My suggestion-------replace batteries every year with top of the line batteries. Don't waste your time on cheap batteries. It will save you a lot of time, grief, and money.