Quote:
I get continuity on the blue pair of 5V jumpers as long as one of them is connected.


Ah. Is this between the pair of pins connected by the jumper, and ground? If you remove the jumpers completely and test between each pin and ground, do you have continuity? If so, my guess is that it's the pins nearest the USB socket?

Assuming yes to the above, this is not good. It means you have a short between the ground rail and the 5v rail. This causes the power supply chip to shut down, killing both 5v and 3.3v.

If this is the case, applying power with the jumpers removed should produce 5v and 3.3v on the relevant headers, on the pins nearest the power supply section. Does it?

pca
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