This is an ongoing issue with Bitmain in general. I too was just hit with a failed part, and the turn around on failed product WILL result in serious loss in mining payouts. There is an advantage to going with Bitmain for mining hardware, however due to their support on hardware with issues, you need to factor in as serious losses in revenue .
Yeah I've accepted that I will probably never reach ROI, and its very frustrating/depressing watching your investment go from bad to worse.
Bad to worse => to worser....
Got the blue screen of death.... S2 turns on but only getting a blank blue LCD display on the S2. I've re-imaged SD card but did nothing. Waiting for a Bitmain to reply for a RMA request.
Don't give up yet. i've had the same thing. try removing all the boards (power off first, of course), then power on. watch the controller board for blue lights. they mean the controller has found a usable boot partition on the SD card and booted from it. if you get it to boot, and can connect to the web page of the controller, then the problem may have been a connection to one of the currently-removed boards. you have to put them back in, but there's a good chance that shutting the system off "hot" will botch the SD image, so you have to ssh into it and shut it down gracefully...
shutdown -h now
wait for it to do so, then power off.
keep us posted.