I just had a similar problem develop on a 2003 1.4 cdi. It only happened after short journeys with heater, lights and de-misters running. The car ran fine until parked, and a few minutes later would not re-start with the promlem you mention. The headlights came on and looked fine. The PATS light ultimately went out. After standing an hour or so, the PATS light flashed normally and the car would start normally. I just changed the battery and cleaned the posts and connectors. So far it hasn't happened again.

Edited by snoot on 07/03/2013 at 01:05