wireness network between two buildings and also cat5

I have a belkin f5d7632-4 that I am trying to connect to a Sitecom AP wl330 using cat5. I have tested locally and all ok, but when I try o connect to the cat5 that is run between our main house and converted garage I don't get a signal. I have noticed that the blue pair of cables are faulty, so I have configured wires 1,2,3,6 on a local cable and all access via the ap to the isp is good. I have connected the same in between buildings and not connection is made.

Any ideas on what my options are to get this to work. The buildings are only about 10-15 metres apart.

I have also tried wireless N routers and no luck either as too far. I want to connect the buildings and was hoping the cat5 would have worked, or the wireless-n. Anyone know how to do this please. ahhhh!