Issues with my FOCBOX (possible short?)

So i’m having some issues with both of my FOCBOX’s. I had a small spark inside my XT60 when plugging the FOCBOX to my battery, however all leads seem to be wired correctly and its a 42V 18650 battery pack that seems to be at an acceptable voltage. When i plug my battery in i get 5v out of all 5v pins but no lights and nothing out of the 3.3v pin. I had read that i can do a continuity check with my multimeter over the c25 capacitor to test if the 5v had been shorted to ground, which it appears it has.

per @JohnnyMeduse post No power to Enertion Vesc

Does this suggest theres an internal short over the CAN transceiver (u401)? And if so, Is there anything i can do to fix this, and can anyone suggest how this might have occurred? here are some photos of my setup…

FOCBOX 1: IMG_6764 IMG_6764.JPG4032x3024 1.61 MB

FOCBOX 2: IMG_3067 IMG_3067.JPG4032x3024 1.69 MB

Battery: IMG_7295 IMG_7295.JPG3024x4032 2.43 MB

Thanks for your time everyone, appreciate any ideas!

Yes… You can either replace those Can chip or Removing them and use split PPM cable.

Do you have any idea how this sort of thing could have occurred? last thing i want to do is replace the chip and then the same thing happens again.

Dont unplug single focbox while they are both on and CAN bus connected it instantly kills CAN chip

EDIT: u can make Y adapter and zip tie each focbox so it wouldn’t disconnect by itself.

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Good tip will keep that in mind! it seemed to happen when i plugged in a single FOCBOX on its own, as thats when i saw a spark in the XT60 (which appears to be burnt at the terminals), but ill definitely only plug/unplug from the single XT90 Y adaptor i made up from now on!

Also any ideas how hard it will be to replace the chip on my own? willing to give it a crack, just not sure where to start…

Easiest way is to get hot air station and just heat that chip up and remove it and and then solder new in. Also u will need probably replace can termination resistor R40* next to chip

This is how my Y splitter looks with zip ties