/diy/ - Do It Yourself

I'm having a really frustrating time with trying to get my heat bed to work. I have tried 2 beds so far and haven't gotten them to heat up at all. The one I'm trying to use has continuity from the power port to the D8 port, I have TEMP_SENSOR_BED set to 11, and BED_MINTEMP set to 5, there is enough power available for it since I have a 400W PSU for the whole thing. The hot end starts heating up but no voltage is measured across the heat bed and after some seconds it fails to detect a change in temperature so it stops with the "Failure to Heat; Reset Device" error.
I'm trying to control it using an attached LCD control screen/sd card reader so it's not hooked up to a computer with repetier or anything.

I've made sure none of the components are touching like the bent MOSFETs or stray wires or anything. I've tried 2 heat beds now and am so tried of this I'm tempted to just try a different arduino mega and ramps board to see if something is just fucked on my current ones.

I don't know what I'm doing wrong, does anyone know what might be the problem?