Having @jack.luis helping me out with fixing my D100s. He said one of the 3.3v rail is reading very low (~0.1v), while the 5.0v rail is reading correctly. Anyone had this issue?
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Maybe a short on that 3.3v circuit? Can you feel anything getting hot? Check for continuity on the +/- of 3.3v each side.
We did all that, one side is reading normally while the other side read super low. Messaged Makerx too and they said the MCU might had been shorted.
if low ohmic between GND and 3.3V then theres a short present.
Start removing stuff until it dissapears (its usually the MCU).
Could also be that the regulator died when short happened.
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could also just be getting hot cause its trying to drive a 0 ohm load 
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Which pads would you check to confirm that?
Checked the resistance between the output and the gnd pin and got 1.4ohm.
Same two pins on the other 3.3v regular gets me 361.4ohm. yikes. You’re definitely right about some kind of short.
@MichaelWA if it’s the stm32 this may not be worth saving/trusting after repair
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If you have 1.4 ohm then that would pull the 3.3V to 0 for sure.
You can carefully lift the output pin so its not connected to the PCB and then see if it its 3.3V on the pin without it beeing connected to anything. If so, the regulator is probably fine.
I would remove the MCU and see if the short dissapears. Swapping MCU is an easy repair, just need to reflash the FW.
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I’ll give that a go next time I have time
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