iphone 3gs won't connect to pc or charge

Hi. My iphone 3gs was water damaged. I let it dry. when i connect to a power source it senses it but will not charge. After about ten minutes of connection to wall or pc, the apple logo comes on and stays there unless i unplug it for a while, then it goes back to the low battery icon. I have replaced the battery and dock connector. is there anything to do next?