zero temperature reading

I have a Gen3 set of boards attached to the mendel I've built and am now commissioning. The axis work fine but i can't get the extruder temperator sensor working - I get 0 as the temperature! I've tried both the reprap software and Repsnapper and both are the same.

I've a couple of spare 100K thermistors and they also show the same thing...

I've attached an image showing the board and the thermistor attached.

Does anyone have any suggestions on what the problem might be or how to diagnose it?

Thanks

Ian

the screw terminal looks kinda twisted, did you secure them by using a hand drill? i did that once and i had to fix it by taking out the screw terminal and soldering the thermistor leads straight to the holes but i would suggest replacing the screw terminal instead of doing that.. turn it over, and with repsnapper open just move the thermistor over the connection skipping the screw terminals and see if you can get a temp reading that way