if its gone into eco mode it cuts out non essential electrics to save battery power normally starting it will take it out but on occasion been in eco mode can stop it starting try disconnecting both battery terminals from battery and joining them together you may have to use a link wire if they wont reach ,then leave it 10 min then remove link wire then refit terminals to battery. make sure battery is fully charged . if it dosent work it might have to go to dealer for them to plug it in to diagnostic computer.
steve, May 2010