its super easy to resolder
How tf am I supposed to do that with this piece of shit
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Hey! I got the same!
Must admit, it is pretty shitty. Currently trying to unsolder the C25 and the solder is not even melting…
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i did it on a 2$ trisonic iron…
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I found the resistor but it seems way to small to even solder and i don’t have a good tip
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What 
Char
I’ll look at this later I can’t be on my phone at work
flux 
This is the hardest thing I’ve ever run into, someone please do this for me!!!
@legend27 If you don’t succeed with the repair and you don’t mind sending it to sweden, I can do this repair for you. (and the STM32 change if its fried). Send a PM in that case.
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Geez… It is literally impossible to make the solder wet. Would a solder heat gun be faster & better?
It does not work like that.
FINALLY GOT C25 OFF!
But it still beeps when I touch 3v3 and GND…
Next step is to unsolder this one, right?
Nice! 
Now when you have removed the capacitor from the circuit you can try and beep it. hopefully it doesn’t beep.
Yes now we want to remove the 3v3 regulator. This is tricky since it has 4 legs. Not sure how I would have started here if I did not have my hot air station 
EDIT: I would put a big solder blob covering all three legs and then do as you did with the capacitor! 
What you DON’T want to do is damaging the foot print on the PCB during this process.
Maybe start de-solder the larger leg first and GENTLY bend the component up a bit so that the pad comes free. But maybe there is to much solder on the pad for this 
Or…If it is possible you could cut the three legs off with a cutting tool tingy, and afterwads remove the big pad… or maybe the space is not enough for that?
Or…De-solder one small leg at a time, bending the leg upwards when it comes loose.
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Thanks for all the tricks!
I tried measuring again and it is still beeping when I touch GND and 3V3.
Really appreciate your help!
Ok… that was less good 
Can you beep the 3v3 regulator now when its removed ? (just too make sure that it was not part of the problem)
The things remaining that sits across 3v3 and gnd should only be the STM32 and the CAN transceiver I believe (Or are there capacitors on the 3v3 rail other than C25? @JohnnyMeduse )
Now a hot air gun would really be useful. Without it, the only thing you could do is to remove the CANtranceiver using the solder blob method. And cross your fingers this is the issue. If you still have a short between 3.3v and Gnd… the STM32 must be replaced and you would need a new CANtransceiver if you want to utilize the CAN feature (unless you can clean up the chip with some solder wick)
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Guys come on!!!
I have said it 5 time already!!! THE MCU IS DEAD…
I have dealt with this issue numerous of time…
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Well, now that we scientifically have ruled out C25 and 3v3 (which would give the same symptom)…and we assume the CANchip is fine since it was never used, then yes I also vote MCU is dead…
I don’t see why spending some time checking the simpler components first is wrong before replacing the much more complicated MCU.
This @legend27 have done by himself this now and probably gave him some experience points 
Until now Legend27 had a fair chance to fix this himself without sending it for repairs.
I mean absolutely no offence to you Mr Meduse. I know you are involved a lot with VESC repairs. You definitely have more statistics of root causes than I do. I have learnt from you. I just want make clear for others what was going on here.
For me this is simple fault tracing… do one bit at a time. Start with the simple things. MCU was never ruled out and here is were we end up.
I have blown them myself and I rather change a 3v3 
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Sadly you blew its mind
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If you opt to attempt to replace the MCU, I would recommend using chip quik if you dont have a high quality hot air station.
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Hey everyone!
Haven’t actually tried any of the other solutions yet, but it just kinda hit me now why it probably broke.
Running 40A battery on a single focbox with stock heat sink in a completely closed enclosure and pushing it a lot doesn’t sound like a great idea.
The reason I had those settings was because, I had ran them on my focbox unity, but now when I think about it, it was probably just 20A for each side of the unity…
Looking forward to try all the solutions when next paycheck arrives
-Thanks guys!
Last words; Learn by others mistakes.
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