bed not heating: low voltage?

[suvl]

After having everything working last night, this morning I tried to print and my bed is not heating at all.

I've noticed that the led near the hot bed power supply was not getting on. It gets on when I unplug the bed.
Video:

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as we can see here, the resistor reading the temp is working:

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I've measured the output and it's under 6 volts, I'm guessing that's the problem. How does one fix this? thanks!