Vaio wireless problem

I have a sony vaio PCG-K415B laptop with built in wireless. Recently I had a repair done to the power jack,but since this was done the wireless wont connect unless you are within 2 metres of the netgear router, if I put the netgear wireless card in it works perfect,right up to range of 20mt. My question, is there an aerial wire inside the vaio that may have become damaged or disconnected, as it seems the signal strength is poor. Your help will be appreciated