Solved X limit switch not working right

I just finished replacing my x carriage for a cable chain mod and now my x axis is screwed up. When I try G28 X, it moves a tiny bit and then it thinks it's correctly homed. If I take out the pins from the limit switch and touch them it is as if the x carraig is touching the switch, then it will go towards the switch as if it were homing correctly.

I'm not sure how to explain this very well, but I believe it is reversed so normally it think's it's homed as soon as it hits the limit switch, but right now it's opposite so it thinks it is homed when it is open. I had my father hold it down and it moved towards it like it should normally as if my father weren't there and as soon as he let go, it though it was correctly homed.

I need to reverse it in the firmware and I don't know what file or line or even what the line would look like.

 

Thank you for the reply. I had the switch connected exactly how it was by default. I fixed it by finding the right line in the firmware and now it works perfectly.