What sort of 12V battery was connected? As the DCDC is susceptible to heavy voltage swings if not providing enough output/stabilisation with a battery.

Also the failure looks like cooking the pcb , possible heatsoak issue from lack of cooling.

Failure mode looks to be blown mosfet. More ...

Connected to a lead acid battery. Generally I would disconnected the PCS once the contactors had clicked in because of not having a circuit set up to handle the slightly higher voltage the PCS wanted to output. I noticed when the lead acid battery was connected to the PCS after contact to closing it ...

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Noted. I couldn't see attachments when I posted

Hi,

Been working on a project using a Tesla model 3 battery pack connected to a solar inverter. Its been running for a few weeks but hit an issue. The contactors are no longer closing. Opened the penthouse to find a suspicious smell. Opened the PCS to look for damage and spotted what's in the ...