Remote key fob inoperable after jump start

[Mouldikh]

I had a flat battery after about 3 weeks inactivity of my 2006 xk.The car has keyless start buy not keyless entry. After first trying to start the car the I got out and the remote key would not lock the car. I successfully jump started the car but the car would not recognise the key and I had to place the key in the starter control unit. I can only open and lock the car with the physical key operating the passenger door. The car ignition does not respond to the key fob but I can start the car ok by placing the fob in the starter control unit. Both keys do not work and batteries have been checked. Can anyone help?

[mike020150]

The key fob is part of a complicated security/start procedure whereby the fob and the car 'talk' with each other during the starting procedure. In this instance, the car has definitely recognised the key because it works in the starter control unit where it is to all intents and purposes hard-wired to the car. If the fobs and their batteries are good, what isn't taking place is the expected RF 'conversation' between the fob and different units in the car, like the central junction box, and as a result the starting and security systems won't work as intended. One possibility is that one or more units may have suffered a voltage spike and will either be damaged and/or need to be reprogrammed. The latter task is only possible using Jaguar's IDS system. When you take your car to a garage with IDS diagnostic capability, ensure you take both keys with you because the test routines adopted may involve reprogramming the system from scratch and both keys will need to be present. Mike.

[Mouldikh]

Mike,

Greatful for the advice. I will do as you say.
Regards, Keith