PS: After pfsense update error LED constantly on and network LEDs flashing

I now tried another serial cable which proved to work on another soekris net6501-30 just fine. On the one with the burning Error LED I still get no output and no input at all on the serial console, network-LEDs at the front keep blinking rapid and randomly. Is there anything I can do or is this box just wrecked now? Is there any way to make sure if it is a hardware fault? How can that even happen after a software update? It was not the first time that I updated pfsense this way, had 2-3 updates before already. The reboot was made by the updater, not by pressing reset switch or turning power off by the way.

>Hello
> have a soekris net6501-30 running constantly for more than a year now.It's running pfsense firewall 
> and I have made several updates on it till now. With the latest update after a reboot, the error light is 
> constantly on and the network port LEDs (all four) are blinking rapidely. The com port doesn't give 
> any output as far as I can see. I also removed the SSD but that doesn't change the error LED or 
> the blinking of the network ports. What does that mean and how can this happen after a simple 
> software update?