No temperature reading - EVER =[ - please help!

Hi all,
Just got my reprap built (with an arduino mega / RAMPs 1.4), and everything works except for the temperature measurements =[. I changed the configuration.h to my particular thermistors, but always got 0 / the lowest value for the temperature. I assumed that must be caused by an open or shorted thermistor circuit, so I tried both shorting the thermistor pins on the RAMPs board together and leaving them open,but got the same temp measurement for both cases! Any tips?

picture of ramps board, and where you are plugging into it.

Wired up like this:
[reprap.org]

I assume the RAMPs thermistor pins should have some voltage across them - can I check for that? What about the connection between the arduino and RAMPs?

Do you think its possible I've blown my MOSFET drivers? Know how I can test for that?