how can i reformat or reset a hardware in a sony ericsson T630? because the camara doesnt wanna turn on, please help me!!!

Settings>Master reset>(reset settings or reset all)>phone code 0000

If you choose "reset all", you will loose all your data! Even in "reset settigs" you will loose some data.

You can check whether your camera or anything else is working properly. To do this press one after the other:
*,(right),*,(left),(left),*,(left),*. When the "service" menu appears, you can then scroll to "service tests" and test everything you want... Hope this will help you!