td4

Can anyone help! I have my Sons freelander td4 2.0l diesel and on Friday I noticed it took a lots of cranking to fire up anyway the next day it wouldn't start, I can hear the fuel pump going under rr wheel arch and have taken the return fuel hose off and fuel is pouring out. I have removed the camshaft sensor but not sure how to test it currently has 12v at 2 pins and earth at the other and centre pin drops voltage when connected and turning over anyone Any Ideas on why it won't start and how to test the cam pos sensor correctly don't want to spend £60 to find its anither issue