Car won't start

[davidbull]

I have a 64 plate 5l cabriolet.
It has developed a fault that appears to occur randomly.
I can come to the car, open the doors with the key fob and the car will not start.
It is like the immobiliser has not turned itself off.
If I leave it for a few hours, the next time I come to it, it will start.
I cannot identify any pattern that causes it.
It occurs every couple of weeks.
My main dealer cannot find a fault and is reluctant to spend any time looking for the fault due to the cost to me.
I would be grateful if anyone can help point me in the right direction.

[steve_m]

I don't know the first thing about F-Types, but have you tried putting a new battery in?

[andypryce]

I would look for a good independent rather than main dealer. That said could well be battery.