My Citroen Xsara Picasso is suffering from an intermitant flat battery - normally on icey mornings.
Most other times (in milder weather), it starts first time.
Have taken it to a 2 garages but they can not find root cause.

Even on icey mornings, it will start first time and then it will trvel for a few miles, but once the engine stops, it will not turn over - due to a flat battery

Kerry Mapps, February 2009

Thought about this overnight - some 206's had a bad batch of starter motors which exhibited some of your symptoms. I'd still try a new battery first, especially if your car is on its original one. (The reason I mention 206's is because Peugeot/Citroen are the same motor group).

Chicks Fan, February 2009

Sounds as if a new battery is required.

Chicks Fan, February 2009