SOLVED...Switching between player controlled cars

Hi all,

I've noticed recently that the player can select to control more than one driver in the driver selection screen. For example select both drivers of the same team.

My question is, how do you change between the drivers you have selected during a race? So far I have only been able to do this when I crash out with one of the drivers selected, but I want to switch and allow the ai to control the driver I've moved away from.

Thanks for the help
Richard