loss of lights on seat leon - revricky

Yesterday the lights failed on my wife's seat leon as she was on the motorway. She managed to get to service station then the engine cut out. She got it restarted but the diagnosis light on the dash remained lit, the `fasten seat belt` light stayed unlit and the central locking would not work. Local seat garage says they have found nothing wrong. Losing headlights, ect, at 60-70 is scary stuff. Anyone else heard of this? PS local air temp was at least -6c.

Thanks for any posts


Value my car