Illness and zero degree weather meant that I did not start my 2009 Mazda 3 for three weeks. When I tried to start the vehicle the battery was flat. The dealer told me it was the extreme cold and they had a 2010 model similarly affected. My niece and nephew had my previous Mazda 3, just two years old with 5,000 on the clock - not exactly overworked. They went to Australia in March and it wasn't cold here. When they got back, my niece’s Focus started without problems, as did her daughter’s Ford Ka and son's Corsa, but the Mazda had to be started with jump leads. Have you heard of other incidences and could it be anything to do with the fancy Thatcham anti-theft alarm system draining the battery if the car is not used regularly?