250 EX no welding current

Hello,
I have a 250 ex from 2010 that just recently stopped working. I was welding with AC at about 200A, and I heard a pop from within the welder, but that may have been the circuit breaker tripping. Now the welder turns on, and I get the HF start, but it wont switch to the welding current. If I try to scratch start, nothing happens.

Can anyone tell me how to go about trouble shooting this? I opened the box and poked around, but I dont see any obvious signs of something burning or blowing up.

Thanks in advance

It has blown IGBT's or diodes. Not much you can do, except send it for repair.

bummer. Is it possible to buy some replacement board and fix it myself?
Thanks for the reply

No, the board is rebuild-able and that is what we do with those older boards. I'm sure we have a few new ones, but are held in reserve for non rebuildable boards. That is why I said to send it in.