2008 Avensis occasionally fails to start- possible ignition fault?

[Crd3]

Hi there. I was wondering if anyone has had a similar problem and/or has a solution to my issue. 

My 2008 Avensis fails to start but I can't see any reason why. It sounds like it's about to start but just fails to get going. No warning lights, etc, makes all the right noises but just doesn't start. The dealer initially said it could be a security/ignition setting with the keys and just locked and unlocked the car several times and then the car started without issues at least 10 times. 2 hours later I sent it back to the dealership as the issue occurred again. They've sent it to their garage which is taking an eternity. They've concluded "there's nothing mechanically wrong, it must be electrical". Apparently the car has started every time the garage has looked at the car so they haven't identified a fault yet... 

[Konrad C]

The last time I heard about this, was near a transmitter mast. But if this happens in other locations, so long as there are no masts, I would look at the fuel pump, and the cam/crank sensors. 
Since the car is at the dealers, they can check on diagnostics.