Bafang Capacitor exploded

[Stusmall]

Hi, have a under 200 miles bafang 48v750w middrive. It stopped after a reported error code 12 and the irreplaceable white smoke left the unit.
I have taken the controller apart and can see that the culprit is the large capacitor which has exploded. While carefully removing potting compound i can see that the control wires were stuck to the capacitor by the grey filler.
Have a new controller coming but thinking of repairing this one for when the next goes pop.
Anyone tried this before?

 

[amberwolf]

If it is *just* the capacitor, it's a relatively easy repair, as you only have to pick off the potting from the capacitor itself, and the PCB directly under it on the other side of the PCB, so you can access the solder pads.

It's not terribly uncommon for electrolytic capacitors to be installed backwards, which will make them explode, or at least to fail by swelling and leaking, so make *sure* that the new capacitor is installed correctly based on verifying where the negative lead connects to battery negative input, and not just matching what the original cap orientation/strip was.

 

[Stusmall]

Thanks for the help, the capacitor has metled through some control wires from the main harness and the wires to the 6v light so I will need to repair those. The rest of the board looks fine apart from the yellow power wire has jumped ship from the board completey.
Going to look at purchasing some better FETS and milling the case for better heat dissipation to see if I can improve this sealed controller for better heat dissipation.