One problem related to battery dead has been reported for the 2009 Ford F-150. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2009 Ford F-150 based on all problems reported for the 2009 F-150.
Truck purchased 3-30-2011. 9-2011 needed to have battery jumped. Cleaned battery posts. Seemed fine. 12-19-2011 battery went dead. Aaa replaced battery. 01-31-2012 battery went dead again. Aaa came and said the battery was fine. Had it jumped and took it to holman in maple shade, NJ. They kept the truck for five days and could not find anything wrong with it. When aaa came they said it seemed as if something was pulling from the battery holman said if it happens again not to have it jumped just have it towed. Seems it may be electrical. Not really sure.