For that phone you need A2UPLOADER and here you have steps for FileSystem [Debrand] A2 (Db3150) Tutorial - Top Sony Forums and read part 2, also you will need flash drivers and that 2 thing you will find here A2-DB3150 Flashing - Top Sony Forums , but I'm not sure if your phone is DB3150, so when you connect with A2UPLOADER post log here without IMEI number