This part fails often due to repetitive plugging/ unplugging of your machine or if someone trips over your cord while it is plugged in. It also contains LHS USB port and light sensor.
The Power Jack, USB Port and Audio in and Out Ports are all part of this board.
This is the part I had replaced a year and a half ago. Grrrr. But since I've got the new computer on the way I am going to order the part and replace it myself to save money.